packages feed

Rasterific 0.7 → 0.7.1

raw patch · 7 files changed

+2641/−2446 lines, 7 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

+ Graphics.Rasterific: Backward :: Direction
+ Graphics.Rasterific: Forward :: Direction
+ Graphics.Rasterific: arcInDirection :: Point -> Float -> Direction -> Float -> Float -> Float -> [PathCommand]
+ Graphics.Rasterific: data Direction

Files

Rasterific.cabal view
@@ -1,100 +1,101 @@--- Initial Rasterific.cabal generated by cabal init.  For further --- documentation, see http://haskell.org/cabal/users-guide/-name:                Rasterific-version:             0.7-synopsis:            A pure haskell drawing engine.--- A longer description of the package.-description:-    <<data:image/png;base64,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>>-    .-    Rasterific is a vector drawing library (a rasterizer)-    implemented in pure haskell.-    .-    Can render vector graphics to an image and export vector data to PDF.--license:             BSD3-license-file:        LICENSE-author:              Vincent Berthoux-maintainer:          twinside@gmail.com---- A copyright notice.--- copyright:           -category:            Graphics-build-type:          Simple---- extra-source-files:  --cabal-version:       >= 1.10-extra-doc-files: docimages/*.png-extra-source-files: changelog-                  , README.md-                  , docimages/*.png-                  , exec-src/docImageGenerator.hs----Source-Repository head-    Type:      git-    Location:  git://github.com/Twinside/Rasterific.git--Source-Repository this-    Type:      git-    Location:  git://github.com/Twinside/Rasterific.git-    Tag:       v0.7--flag embed_linear-  description: Embed a reduced version of Linear avoiding a (huge) dep-  Default: True--library-  hs-source-dirs: src-  exposed-modules: Graphics.Rasterific-                 , Graphics.Rasterific.Outline-                 , Graphics.Rasterific.Texture-                 , Graphics.Rasterific.Linear-                 , Graphics.Rasterific.Lenses-                 , Graphics.Rasterific.Transformations-                 , Graphics.Rasterific.Immediate-                 , Graphics.Rasterific.PathWalker-                 , Graphics.Rasterific.Patch-                 , Graphics.Rasterific.BiSampleable-                 , Graphics.Rasterific.MeshPatch--  other-modules: Graphics.Rasterific.Line-               , Graphics.Rasterific.Command-               , Graphics.Rasterific.CubicBezier-               , Graphics.Rasterific.QuadraticBezier-               , Graphics.Rasterific.Operators-               , Graphics.Rasterific.Rasterize-               , Graphics.Rasterific.StrokeInternal-               , Graphics.Rasterific.ComplexPrimitive-               , Graphics.Rasterific.Types-               , Graphics.Rasterific.Compositor-               , Graphics.Rasterific.MicroPdf-               , Graphics.Rasterific.MiniLens-               , Graphics.Rasterific.Shading-               , Graphics.Rasterific.PlaneBoundable-               , Graphics.Rasterific.QuadraticFormula-               , Graphics.Rasterific.PatchTypes-               , Graphics.Rasterific.CubicBezier.FastForwardDifference--  ghc-options: -O3 -Wall -  -- -ddump-simpl -ddump-to-file -dsuppress-module-prefixes -dsuppress-uniques-  default-language: Haskell2010-  build-depends: base        >= 4.5     && < 5-               , free        >= 4.7-               , JuicyPixels >= 3.2-               , FontyFruity >= 0.5.3.2 && < 0.6-               , vector      >= 0.9-               , mtl         >= 1.9-               , dlist       >= 0.6-               , primitive   >= 0.5-               , vector-algorithms >= 0.3-               , bytestring  >= 0.10.2-               , containers  >= 0.5-               , transformers--  if !flag(embed_linear)-      build-depends: linear >= 1.3-      cpp-options: -DEXTERNAL_LINEAR-+-- Initial Rasterific.cabal generated by cabal init.  For further 
+-- documentation, see http://haskell.org/cabal/users-guide/
+name:                Rasterific
+version:             0.7.1
+synopsis:            A pure haskell drawing engine.
+-- A longer description of the package.
+description:
+    <<data:image/png;base64,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>>
+    .
+    Rasterific is a vector drawing library (a rasterizer)
+    implemented in pure haskell.
+    .
+    Can render vector graphics to an image and export vector data to PDF.
+
+license:             BSD3
+license-file:        LICENSE
+author:              Vincent Berthoux
+maintainer:          twinside@gmail.com
+
+-- A copyright notice.
+-- copyright:           
+category:            Graphics
+build-type:          Simple
+
+-- extra-source-files:  
+
+cabal-version:       >= 1.10
+extra-doc-files: docimages/*.png
+extra-source-files: changelog
+                  , README.md
+                  , docimages/*.png
+                  , exec-src/docImageGenerator.hs
+
+
+
+Source-Repository head
+    Type:      git
+    Location:  git://github.com/Twinside/Rasterific.git
+
+Source-Repository this
+    Type:      git
+    Location:  git://github.com/Twinside/Rasterific.git
+    Tag:       v0.7.1
+
+flag embed_linear
+  description: Embed a reduced version of Linear avoiding a (huge) dep
+  Default: True
+
+library
+  hs-source-dirs: src
+  exposed-modules: Graphics.Rasterific
+                 , Graphics.Rasterific.Outline
+                 , Graphics.Rasterific.Texture
+                 , Graphics.Rasterific.Linear
+                 , Graphics.Rasterific.Lenses
+                 , Graphics.Rasterific.Transformations
+                 , Graphics.Rasterific.Immediate
+                 , Graphics.Rasterific.PathWalker
+                 , Graphics.Rasterific.Patch
+                 , Graphics.Rasterific.BiSampleable
+                 , Graphics.Rasterific.MeshPatch
+
+  other-modules: Graphics.Rasterific.Line
+               , Graphics.Rasterific.Command
+               , Graphics.Rasterific.CubicBezier
+               , Graphics.Rasterific.QuadraticBezier
+               , Graphics.Rasterific.Operators
+               , Graphics.Rasterific.Rasterize
+               , Graphics.Rasterific.StrokeInternal
+               , Graphics.Rasterific.ComplexPrimitive
+               , Graphics.Rasterific.Types
+               , Graphics.Rasterific.Compositor
+               , Graphics.Rasterific.MicroPdf
+               , Graphics.Rasterific.MiniLens
+               , Graphics.Rasterific.Shading
+               , Graphics.Rasterific.PlaneBoundable
+               , Graphics.Rasterific.QuadraticFormula
+               , Graphics.Rasterific.PatchTypes
+               , Graphics.Rasterific.CubicBezier.FastForwardDifference
+               , Graphics.Rasterific.Arc
+
+  ghc-options: -O3 -Wall 
+  -- -ddump-simpl -ddump-to-file -dsuppress-module-prefixes -dsuppress-uniques
+  default-language: Haskell2010
+  build-depends: base        >= 4.5     && < 5
+               , free        >= 4.7
+               , JuicyPixels >= 3.2
+               , FontyFruity >= 0.5.3.2 && < 0.6
+               , vector      >= 0.9
+               , mtl         >= 1.9
+               , dlist       >= 0.6
+               , primitive   >= 0.5
+               , vector-algorithms >= 0.3
+               , bytestring  >= 0.10.2
+               , containers  >= 0.5
+               , transformers
+
+  if !flag(embed_linear)
+      build-depends: linear >= 1.3
+      cpp-options: -DEXTERNAL_LINEAR
+
changelog view
@@ -1,147 +1,158 @@-Change log-==========--v0.6.1.1 May 2016-------------------- * Fix: GHC 8.0 bound fix--v0.6.1 May 2015------------------ * Fix: Correcting bytestring lower bounds--v0.6 May 2015---------------- * Adding: repeating background pattern texture.- * Added: PDF output without images (for now)--v0.5.2.1 April 2015---------------------- * Fixed: non-composability of cached elements- * Fixed: Border size when drawing images was twice too large.--v0.5.2 April 2015-------------------- * Enhancement: Added a withGroupOpacity to render elements with-   a global opacity.--v0.5.1 March 2015-------------------- * Enhancement: Generalizing geometry description, with automatic-   conversion, reducing the need of type constructor from Primitive,-   and directly filling Path.--v0.5.0.3 February 2015------------------------- * Fix: hackage documentation--v0.5.0.2 February 2015------------------------ * Removing test-suite as it's dependent of some repository-local files--v0.5.0.1 February 2015------------------------ * Fix: adding missing Arbitrary file in the distribution.--v0.5 February 2015--------------------- * Breaking Change: Font size is now a newtype in FontyFruity,-   propagating the changes.- * Allowing to specify DPI at the top level of the rendering-   request.- * Adding: an helper function to retrieve the distance to the- * Changed: font size switched to float.--v0.4.2 February 2015---------------------- * Fix: Cubic bezier clipping--v0.4.1 January 2015--------------------- * Fix: GHC 7.10 compilation- * Adding: Various lens to access some primitive informations.--v0.4 December 2014--------------------- * Breaking change: Changed the original position scheme for-   text, allowing to specify baseline or upper left corner-- * Tried: Fast forward differencing for cubic bezier, not worth-   the hassle- * Enhancement: Further optimized decomposition of all primitives,-   less alocated memory.- * Enhancement: After optimizing pixel writing, optimized pixel-   reading, yielding non-negligeable speed improvements.- * Added: an "immediate" module to avoid constructing-   a scene tree.- * Enhancement: Allowing both IO & (ST s) as drawing monads, enabling-   interleaved drawing with io operations.- * Added: a "withPathOrientation" function to orient primitives-   on a path (allow to draw curved text)- * Added: toNewXBase transformation to create a new basis given-   a X axis vector.- * Added: a PathWalker module, to give access to the lower level-   path orientation facility.- * Added: some GHC rules for transformations- * Added: a new text function: 'printTextRanges' to allow-   easier complex text rendering--v0.3 June 2014----------------- * Enhancement: Switching main free monad type to the church encoded one.- * Enhancement: Optimized the bezier decomposition, strictness annotations-   made wonders. May require forward differencing in the future.- * Enhancement: Implementing specific decomposition for lines.- * Enhancement: Reworked texture system, now allowing some specialized-   filler (hoping faster computation). For now only the-   solid color has been optimized, and all the transformed-   textures.- * Enhancement: Fixing space leak in combineEdgeSamples, avoiding-   many allocations.- * Adding: bounding box calculation facility.- * Adding: Exposing outline creation capability- * Adding: a skewX & skewY transformation function.- * Fixing: some numerical stability with the mitter join.--v0.2.1 April 2014-------------------- * Fixing: transparency in gradients.- * Fixing: alpha composition on top of translucent-   background.--v0.2 April 2014------------------ * Adding: an ellipse helper.- * Adding: a polyline helper.- * Adding: a polygon helper.- * Adding: monoid instance for Drawing.- * Fixing: some stroking bug with cubic bezier curve.- * Fixing: some documentation snippets.- * Adding: a rounded rectangle helper.- * Added: a even-odd filling rule.- * Added: an offset for dashed stroking.- * Added: a transformation module.- * Change: Changed the Transformable typeclass, splitted-   it in two.- * Added: a dumping function for the constructed-   drawing.- * Adding: an image texture with bilinear filtering.- * Adding: an image helper.- * Enhancement: Some modest performance gain.--v0.1 February 2014--------------------- * Initial version.-+Change log
+==========
+
+v0.7.1
+------
+
+ * Addition: arc path helper
+ * Fix: Composition of clip path with transformation.
+
+V0.7
+----
+
+ * Addition: Gradient Mesh!
+
+v0.6.1.1 May 2016
+-----------------
+
+ * Fix: GHC 8.0 bound fix
+
+v0.6.1 May 2015
+---------------
+
+ * Fix: Correcting bytestring lower bounds
+
+v0.6 May 2015
+-------------
+
+ * Adding: repeating background pattern texture.
+ * Added: PDF output without images (for now)
+
+v0.5.2.1 April 2015
+-------------------
+
+ * Fixed: non-composability of cached elements
+ * Fixed: Border size when drawing images was twice too large.
+
+v0.5.2 April 2015
+-----------------
+
+ * Enhancement: Added a withGroupOpacity to render elements with
+   a global opacity.
+
+v0.5.1 March 2015
+-----------------
+
+ * Enhancement: Generalizing geometry description, with automatic
+   conversion, reducing the need of type constructor from Primitive,
+   and directly filling Path.
+
+v0.5.0.3 February 2015
+----------------------
+
+ * Fix: hackage documentation
+
+v0.5.0.2 February 2015
+----------------------
+ * Removing test-suite as it's dependent of some repository-local files
+
+v0.5.0.1 February 2015
+----------------------
+ * Fix: adding missing Arbitrary file in the distribution.
+
+v0.5 February 2015
+------------------
+
+ * Breaking Change: Font size is now a newtype in FontyFruity,
+   propagating the changes.
+ * Allowing to specify DPI at the top level of the rendering
+   request.
+ * Adding: an helper function to retrieve the distance to the
+ * Changed: font size switched to float.
+
+v0.4.2 February 2015
+--------------------
+ * Fix: Cubic bezier clipping
+
+v0.4.1 January 2015
+-------------------
+ * Fix: GHC 7.10 compilation
+ * Adding: Various lens to access some primitive informations.
+
+v0.4 December 2014
+------------------
+
+ * Breaking change: Changed the original position scheme for
+   text, allowing to specify baseline or upper left corner
+
+ * Tried: Fast forward differencing for cubic bezier, not worth
+   the hassle
+ * Enhancement: Further optimized decomposition of all primitives,
+   less alocated memory.
+ * Enhancement: After optimizing pixel writing, optimized pixel
+   reading, yielding non-negligeable speed improvements.
+ * Added: an "immediate" module to avoid constructing
+   a scene tree.
+ * Enhancement: Allowing both IO & (ST s) as drawing monads, enabling
+   interleaved drawing with io operations.
+ * Added: a "withPathOrientation" function to orient primitives
+   on a path (allow to draw curved text)
+ * Added: toNewXBase transformation to create a new basis given
+   a X axis vector.
+ * Added: a PathWalker module, to give access to the lower level
+   path orientation facility.
+ * Added: some GHC rules for transformations
+ * Added: a new text function: 'printTextRanges' to allow
+   easier complex text rendering
+
+v0.3 June 2014
+--------------
+
+ * Enhancement: Switching main free monad type to the church encoded one.
+ * Enhancement: Optimized the bezier decomposition, strictness annotations
+   made wonders. May require forward differencing in the future.
+ * Enhancement: Implementing specific decomposition for lines.
+ * Enhancement: Reworked texture system, now allowing some specialized
+   filler (hoping faster computation). For now only the
+   solid color has been optimized, and all the transformed
+   textures.
+ * Enhancement: Fixing space leak in combineEdgeSamples, avoiding
+   many allocations.
+ * Adding: bounding box calculation facility.
+ * Adding: Exposing outline creation capability
+ * Adding: a skewX & skewY transformation function.
+ * Fixing: some numerical stability with the mitter join.
+
+v0.2.1 April 2014
+-----------------
+
+ * Fixing: transparency in gradients.
+ * Fixing: alpha composition on top of translucent
+   background.
+
+v0.2 April 2014
+---------------
+
+ * Adding: an ellipse helper.
+ * Adding: a polyline helper.
+ * Adding: a polygon helper.
+ * Adding: monoid instance for Drawing.
+ * Fixing: some stroking bug with cubic bezier curve.
+ * Fixing: some documentation snippets.
+ * Adding: a rounded rectangle helper.
+ * Added: a even-odd filling rule.
+ * Added: an offset for dashed stroking.
+ * Added: a transformation module.
+ * Change: Changed the Transformable typeclass, splitted
+   it in two.
+ * Added: a dumping function for the constructed
+   drawing.
+ * Adding: an image texture with bilinear filtering.
+ * Adding: an image helper.
+ * Enhancement: Some modest performance gain.
+
+v0.1 February 2014
+------------------
+
+ * Initial version.
+
exec-src/docImageGenerator.hs view
@@ -1,580 +1,572 @@-{-# LANGUAGE CPP #-}--#if !MIN_VERSION_base(4,8,0)-import Control.Applicative( (<*>), (<$>) )-#endif---import Control.Monad( forM_ )-import Control.Monad.ST( runST )-import Data.Monoid( (<>) )-import Codec.Picture-import Codec.Picture.Types( promoteImage )-import Graphics.Text.TrueType( loadFontFile )-import Graphics.Rasterific-import Graphics.Rasterific.Outline-import Graphics.Rasterific.Texture-import Graphics.Rasterific.Transformations-import Graphics.Rasterific.MeshPatch-import Graphics.Rasterific.Immediate-import System.Directory( createDirectoryIfMissing )-import System.FilePath( (</>) )-import qualified Data.ByteString.Lazy as LB-import qualified Data.Vector as V--import Graphics.Rasterific.Linear( (^+^) )--logo :: Int -> Bool -> Vector -> [Primitive]-logo size inv offset =-    toPrimitives . bezierFromPath . way $ map (^+^ offset)-    [ (V2   0  is)-    , (V2   0   0)-    , (V2  is   0)-    , (V2 is2   0)-    , (V2 is2  is)-    , (V2 is2 is2)-    , (V2  is is2)-    , (V2  0  is2)-    , (V2  0   is)-    ]-  where is = fromIntegral size-        is2 = is + is--        way | inv = reverse-            | otherwise = id--backgroundColor :: PixelRGBA8-backgroundColor = PixelRGBA8 255 255 255 255--frontColor, accentColor, accent2Color :: PixelRGBA8-frontColor = PixelRGBA8 0 0x86 0xc1 255-accentColor = PixelRGBA8 0xff 0xf4 0xc1 255-accent2Color = PixelRGBA8 0xFF 0x53 0x73 255--frontTexture, accentTexture, accent2Texture :: Texture PixelRGBA8-frontTexture = uniformTexture frontColor-accentTexture = uniformTexture accentColor-accent2Texture = uniformTexture accent2Color--produceDocImageAtSize :: Int -> Int -> FilePath -> Drawing PixelRGBA8 () -> IO ()-produceDocImageAtSize width height filename drawing = do-    putStrLn $ "Producing " <> filename-    writePng filename img-    writePdf $ filename <> ".draw.pdf"-    writeOrderPdf $ filename <> ".order.pdf"-  where-    img = renderDrawing width height backgroundColor-        $ withTexture frontTexture drawing--    writeOrderPdf fname =-      LB.writeFile fname .-        renderOrdersAtDpiToPdf width height 92 $-          drawOrdersOfDrawing width height 92 (PixelRGBA8 0 0 0 0) $-            withTexture frontTexture drawing--    writePdf fname =-      LB.writeFile fname .-        renderDrawingAtDpiToPDF width height 92 $-            withTexture frontTexture drawing--produceDocImage :: FilePath -> Drawing PixelRGBA8 () -> IO ()-produceDocImage = produceDocImageAtSize 200 200--capTester :: (FilePath, Cap) -> IO ()-capTester (filename, cap) =-    produceDocImage filename $ do-        stroke 30 JoinRound (cap, cap) base_stroke-        withTexture accentTexture $-            stroke 2 JoinRound (cap, cap) base_stroke-  where -    base_stroke = line (V2 0 200) (V2 100 100)--joinTester :: (FilePath, Join) -> IO ()-joinTester (filename, join) =-    produceDocImage filename $ do-        stroke 30 join (CapRound, CapRound) base_stroke-        withTexture accentTexture $-            stroke 2 join (CapRound, CapRound) base_stroke-  where -    base_stroke =-        [ Line (V2 0 200) (V2 100 100)-        , Line (V2 100 100) (V2 200 200)-        ]--samplerTester :: (FilePath, SamplerRepeat) -> IO ()-samplerTester (filename, sampler) =-    produceDocImage filename $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTexture (withSampler sampler $ linearGradientTexture gradDef-                        (V2 80 100) (V2 120 110)) $-            fill $ rectangle (V2 10 10) 180 180)--outFolder :: FilePath-outFolder = "docimages"--moduleExample :: IO ()-moduleExample = do-  let drawColor = PixelRGBA8 0 0x86 0xc1 255-      recColor = PixelRGBA8 0xFF 0x53 0x73 255-      img =-         withTexture (uniformTexture drawColor) $ do-            fill $ circle (V2 0 0) 30-            stroke 4 JoinRound (CapRound, CapRound) $-                   circle (V2 400 200) 40-            withTexture (uniformTexture recColor) .-                fill $ rectangle (V2 100 100) 200 100--  produceDocImageAtSize 400 200 (outFolder </> "module_example.png") img--sansSerifFont :: FilePath-sansSerifFont = "test_fonts/DejaVuSans.ttf"--monospaceFont :: FilePath-monospaceFont =  "test_fonts/DejaVuSansMono.ttf"--textOnPathExample :: IO ()-textOnPathExample = do-  fontErr <- loadFontFile sansSerifFont-  case fontErr of-    Left err -> putStrLn err-    Right font ->-      let path = Path (V2 100 180) False-                      [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]-      in-      produceDocImage (outFolder </> "text_on_path.png") $ do-        stroke 3 JoinRound (CapStraight 0, CapStraight 0) path--        withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $ do-          withPathOrientation path 0 $-            printTextAt font (PointSize 24) (V2 0 0) "Text on path"--geometryOnPath :: IO ()-geometryOnPath = do-  fontErr <- loadFontFile sansSerifFont-  case fontErr of-    Left err -> putStrLn err-    Right font ->-      produceDocImage (outFolder </> "geometry_on_path.png") $ do-        let path = Path (V2 100 180) False-                        [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]-        withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $-          stroke 3 JoinRound (CapStraight 0, CapStraight 0) path-     -        withPathOrientation path 0 $ do-          printTextAt font (PointSize 24) (V2 0 0) "TX"-          fill $ rectangle (V2 (-10) (-10)) 30 20-          fill $ rectangle (V2 45 0) 10 20-          fill $ rectangle (V2 60 (-10)) 20 20-          fill $ rectangle (V2 100 (-15)) 20 50--textExample :: IO ()-textExample = do-  fontErr <- loadFontFile sansSerifFont-  case fontErr of-    Left err -> putStrLn err-    Right font ->-      produceDocImageAtSize 300 70 (outFolder </> "text_example.png")-          . withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $-                  printTextAt font (PointSize 12) (V2 20 40) "A simple text test!"--textMultipleExample :: IO ()-textMultipleExample = do-  eitherFont1 <- loadFontFile sansSerifFont-  eitherFont2 <- loadFontFile monospaceFont-  case (,) <$> eitherFont1 <*> eitherFont2 of-    Left err -> putStrLn err-    Right (font1, font2) ->-      produceDocImageAtSize 300 70 (outFolder </> "text_complex_example.png") $-          let blackTexture =-                Just . uniformTexture $ PixelRGBA8 0 0 0 255-              redTexture =-                Just . uniformTexture $ PixelRGBA8 255 0 0 255-          in-          printTextRanges (V2 20 40)-            [ TextRange font1 (PointSize 12) "A complex " blackTexture-            , TextRange font2 (PointSize 8) "text test" redTexture]--coordinateSystem :: IO ()-coordinateSystem = do-    fontErr <- loadFontFile sansSerifFont-    case fontErr of-        Left err -> putStrLn err-        Right font -> -            produceDocImage (outFolder </> "coordinate.png") $ create font-  where-    black = PixelRGBA8   0   0   0 255-    stroker = stroke 4 JoinRound (CapStraight 0, CapStraight 0)-    create font = withTexture (uniformTexture black) $ do-        stroker $ line (V2 10 40) (V2 190 40)-        stroker $ line (V2 40 10) (V2 40 190)-        printTextAt font (PointSize 12) (V2 4 37) "(0,0)"-        printTextAt font (PointSize 12) (V2 100 37) "(width, 0)"-        printTextAt font (PointSize 12) (V2 57 190) "(0, height)"-        fill $ Path (V2 170 30) True-            [PathLineTo (V2 195 40), PathLineTo (V2 170 50)]-        fill $ Path (V2 30 170) True-            [PathLineTo (V2 40 195), PathLineTo (V2 50 170)]--fillingSample :: FillMethod -> Drawing px ()-fillingSample fillMethod = fillWithMethod fillMethod geometry where-  geometry = transform (applyTransformation $ scale 0.35 0.4-                                           <> translate (V2 (-80) (-180)))-     [ Path (V2 484 499) True-         [ PathCubicBezierCurveTo (V2 681 452) (V2 639 312) (V2 541 314)-         , PathCubicBezierCurveTo (V2 327 337) (V2 224 562) (V2 484 499)-         ]-     , Path (V2 136 377) True-         [ PathCubicBezierCurveTo (V2 244 253) (V2 424 420) (V2 357 489)-         , PathCubicBezierCurveTo (V2 302 582) (V2 47 481) (V2 136 377)-         ]-     , Path (V2 340 265) True-         [ PathCubicBezierCurveTo (V2 64 371) (V2 128 748) (V2 343 536)-         , PathCubicBezierCurveTo (V2 668 216) (V2 17 273) (V2 367 575)-         , PathCubicBezierCurveTo (V2 589 727) (V2 615 159) (V2 340 265)-         ]-     ]--immediateDrawExample :: Image PixelRGBA8-immediateDrawExample = runST $-  runDrawContext 200 200 (PixelRGBA8 0 0 0 255) $-    fillWithTexture FillWinding texture geometry-  where-    circlePrimitives = circle (V2 100 100) 50-    geometry = strokize 4 JoinRound (CapRound, CapRound) circlePrimitives-    texture = uniformTexture (PixelRGBA8 255 255 255 255)--immediateDrawMaskExample :: Image PixelRGBA8-immediateDrawMaskExample = runST $-  runDrawContext 200 200 (PixelRGBA8 0 0 0 255) $-    forM_ [1 .. 10] $ \ix ->-       fillWithTextureAndMask FillWinding texture mask $-           rectangle (V2 10 (ix * 18 - 5)) 180 13-  where-    texture = uniformTexture $ PixelRGBA8 0 0x86 0xc1 255-    mask = sampledImageTexture-         $ runST-         $ runDrawContext 200 200 0-         $ fillWithTexture FillWinding (uniformTexture 255) maskGeometry--    maskGeometry = strokize 15 JoinRound (CapRound, CapRound)-                 $ circle (V2 100 100) 80--main :: IO ()-main = do-    let addFolder (p, v) = (outFolder </> p, v)-    createDirectoryIfMissing True outFolder-    moduleExample-    mapM_ (capTester . addFolder)-        [ ("cap_straight.png", CapStraight 0)-        , ("cap_straight_1.png", CapStraight 1)-        , ("cap_round.png", CapRound)-        ]--    mapM_ (joinTester . addFolder)-        [ ("join_round.png", JoinRound)-        , ("join_miter.png", JoinMiter 0)-        , ("join_miter_5.png", JoinMiter 5)-        ]--    mapM_ (samplerTester . addFolder)-        [ ("sampler_pad.png", SamplerPad)-        , ("sampler_repeat.png", SamplerRepeat)-        , ("sampler_reflect.png", SamplerReflect)-        ]--    writePng (outFolder </> "immediate_fill.png") immediateDrawExample-    writePng (outFolder </> "immediate_mask.png") immediateDrawMaskExample --    produceDocImage (outFolder </> "fill_circle.png") $-        fill $ circle (V2 100 100) 75 --    produceDocImage (outFolder </> "fill_ellipse.png") $-        fill $ ellipse (V2 100 100) 75 30--    produceDocImage (outFolder </> "stroke_circle.png") $-        stroke 5 JoinRound (CapRound, CapRound) $ circle (V2 100 100) 75 --    produceDocImage (outFolder </> "dashed_stroke.png") $-        dashedStroke [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $-            line (V2 0 100) (V2 200 100)--    produceDocImage (outFolder </> "dashed_stroke_with_offset.png") $-        dashedStrokeWithOffset 3 [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $-            line (V2 0 100) (V2 200 100)--    produceDocImage (outFolder </> "fill_rect.png") $-        fill $ rectangle (V2 30 30) 150 100--    produceDocImage (outFolder </> "with_texture.png") $-      withTexture frontTexture $ do-          fill $ circle (V2 50 50) 20-          fill $ circle (V2 100 100) 20-          withTexture accent2Texture $-               fill $ circle (V2 150 150) 20--    produceDocImage (outFolder </> "strokize_path.png") $-      stroke 3 (JoinMiter 0) (CapStraight 0, CapStraight 0) $-          strokize 40 JoinRound (CapRound, CapRound) $-            CubicBezier (V2  40 160) (V2 40   40)-                        (V2 160  40) (V2 160 160)--    produceDocImage (outFolder </> "strokize_dashed_path.png") $-      mapM_ (stroke 3 (JoinMiter 0) (CapStraight 0, CapStraight 0)) $-          dashedStrokize 0 [10, 5]-                         40 JoinRound (CapStraight 0, CapStraight 0)-            [CubicBezier (V2  40 160) (V2 40   40)-                         (V2 160  40) (V2 160 160)]--    produceDocImage (outFolder </> "with_clipping.png") $-      withClipping (fill $ circle (V2 100 100) 75) $-          mapM_ (stroke 7 JoinRound (CapRound, CapRound))-            [line (V2 0 yf) (V2 200 (yf + 10)) -                           | y <- [5 :: Int, 17 .. 200]-                           , let yf = fromIntegral y ]--    {-produceDocImage (outFolder </> "clip_compose.png") $-}--    produceDocImage (outFolder </> "stroke_line.png") $-      stroke 17 JoinRound (CapRound, CapRound) $-        line (V2 10 10) (V2 180 170)--    produceDocImage (outFolder </> "linear_gradient.png") $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTexture (linearGradientTexture gradDef (V2 40 40) (V2 130 130)) $-            fill $ circle (V2 100 100) 100)--    produceDocImage (outFolder </> "linear_gradient_rotated.png") $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTransformation (rotate 1) $-          withTexture (linearGradientTexture gradDef (V2 40 40) (V2 130 130)) $-              fill $ circle (V2 100 100) 100)--    produceDocImage (outFolder </> "radial_gradient.png") $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTexture (radialGradientTexture gradDef (V2 100 100) 75) $-            fill $ circle (V2 100 100) 100)--    produceDocImage (outFolder </> "radial_gradient_focus.png") $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTexture (radialGradientWithFocusTexture gradDef (V2 100 100) 75 (V2 70 70)) $-            fill $ circle (V2 100 100) 100)--    produceDocImage (outFolder </> "sampler_pad.png") $-       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)-                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)-                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in-        withTexture (linearGradientTexture gradDef (V2 80 100) (V2 120 110)) $-            fill $ rectangle (V2 10 10) 180 180)--    produceDocImage (outFolder </> "logo.png") $ do-      let colorCycle = cycle-            [ PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xDf 0xD4 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255]-          colors = V.fromListN (4 * 4) colorCycle-          mesh = generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors-      withTexture (transformTexture (scale 0.7 0.7 <> rotateCenter (-0.4) (V2 100 100)) $-                    meshPatchTexture PatchBicubic mesh) $-        fill $ logo 80 False (V2 20 20) ++ -               logo 40 True (V2 40 40)--    produceDocImage (outFolder </> "cubic_bezier.png") $-        stroke 5 JoinRound (CapRound, CapRound) $-            CubicBezier (V2 0 10) (V2 205 250)-                        (V2 (-10) 250) (V2 160 35)--    produceDocImage (outFolder </> "quadratic_bezier.png") $-        fill [ Bezier (V2 10 10) (V2 200 50) (V2 200 100)-             , Bezier (V2 200 100) (V2 150 200) (V2 120 175)-             , Bezier (V2 120 175) (V2 30 100) (V2 10 10)]--    produceDocImage (outFolder </> "simple_line.png") $-        fill [ Line (V2 10 10) (V2 190 10)-             , Line (V2 190 10) (V2 95 170)-             , Line (V2 95 170) (V2 10 10) ]--    produceDocImage (outFolder </> "primitive_mixed.png") $-        fill-            [ toPrim $ CubicBezier (V2 50 20) (V2 90 60)-                                   (V2  5 100) (V2 50 140)-            , toPrim $ Line (V2 50 140) (V2 120 80)-            , toPrim $ Line (V2 120 80) (V2 50 20) ]--    produceDocImage (outFolder </> "path_example.png") $-       fill $ Path (V2 50 20) True-          [ PathCubicBezierCurveTo (V2 90 60) (V2  5 100) (V2 50 140)-          , PathLineTo (V2 120 80) ]--    produceDocImage (outFolder </> "stroke_polyline.png") $-        stroke 4 JoinRound (CapRound, CapRound) $-            polyline [V2 10 10, V2 100 70, V2 190 190]--    produceDocImage (outFolder </> "fill_polygon.png") $-        fill $ polygon [V2 30 30, V2 100 70, V2 80 170]--    produceDocImage  (outFolder </> "fill_roundedRectangle.png") $-        fill $ roundedRectangle (V2 10 10) 150 150 20 10--    produceDocImage  (outFolder </> "stroke_roundedRectangle.png") $-        stroke 4 JoinRound (CapRound, CapRound) $-            roundedRectangle (V2 10 10) 150 150 20 10--    produceDocImage (outFolder </> "fill_evenodd.png") $-        fillingSample FillEvenOdd--    produceDocImage (outFolder </> "fill_winding.png") $-        fillingSample FillWinding--    produceDocImage (outFolder </> "transform_rotate.png") $-        fill . transform (applyTransformation $ rotate 0.2)-             $ rectangle (V2 40 40) 120 120--    produceDocImage (outFolder </> "transform_rotate_center.png") $-        fill . transform (applyTransformation $ rotateCenter 0.2 (V2 200 200))-             $ rectangle (V2 40 40) 120 120--    produceDocImage (outFolder </> "transform_translate.png") $-        fill . transform (applyTransformation $ translate (V2 100 100))-             $ rectangle (V2 40 40) 40 40--    produceDocImage (outFolder </> "transform_scale.png") $-        fill . transform (applyTransformation $ scale 2 2)-             $ rectangle (V2 40 40) 40 40--    produceDocImage (outFolder </> "transform_skewx.png") $-        fill . transform (applyTransformation $ skewX 0.3)-             $ rectangle (V2 50 50) 80 80--    produceDocImage (outFolder </> "transform_skewy.png") $-        fill . transform (applyTransformation $ skewY 0.3)-             $ rectangle (V2 50 50) 80 80--    Right (ImageRGB8 img) <- readImage "avatar.png"-    let textureImage = promoteImage img-    produceDocImage (outFolder </> "sampled_texture_repeat.png") $-        withTexture (withSampler SamplerRepeat $-                        sampledImageTexture textureImage) $-            fill $ rectangle (V2 0 0) 200 200--    produceDocImage (outFolder </> "image_simple.png") $-        drawImage textureImage 0 (V2 30 30)--    produceDocImage (outFolder </> "image_resize.png") $-        drawImageAtSize textureImage 2 (V2 30 30) 128 128--    produceDocImage (outFolder </> "sampled_texture_reflect.png") $-        withTexture (withSampler SamplerReflect $-                        sampledImageTexture textureImage) $-            fill $ rectangle (V2 0 0) 200 200--    produceDocImage (outFolder </> "sampled_texture_pad.png") $-        withTexture (sampledImageTexture textureImage) $-            fill $ rectangle (V2 0 0) 200 200--    produceDocImage (outFolder </> "sampled_texture_rotate.png") $-        withTexture (withSampler SamplerRepeat $-                    transformTexture (rotateCenter 1 (V2 0 0))-                    $ sampledImageTexture textureImage) $-            fill $ rectangle (V2 0 0) 200 200--    produceDocImage (outFolder </> "sampled_texture_scaled.png") $-        withTexture (withSampler SamplerRepeat $-                    transformTexture (rotateCenter 1 (V2 0 0) <> -                                      scale 0.5 0.25)-                    $ sampledImageTexture textureImage) $-            fill $ rectangle (V2 0 0) 200 200--    produceDocImage (outFolder </> "group_opacity.png") $ do-        withTexture accent2Texture $-            stroke 3 JoinRound (CapRound, CapRound) $-                line (V2 0 100) (V2 200 100)--        withGroupOpacity 128 $ do-           withTexture frontTexture . fill $ circle (V2 70 100) 60-           withTexture accentTexture . fill $ circle (V2 120 100) 60--    produceDocImage (outFolder </> "pattern_texture.png") $-        let pattern =-              patternTexture 40 40 96 accent2Color .-                withTexture frontTexture $-                  fill $ circle (V2 20 20) 13-        in-        withTexture pattern $-          fill $ roundedRectangle (V2 20 20) 160 160 20 20--    produceDocImage (outFolder </> "item_opacity.png") $ do-        withTexture accent2Texture $-            stroke 3 JoinRound (CapRound, CapRound) $-                line (V2 0 100) (V2 200 100)--        withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 128) .-            fill $ circle (V2 70 100) 60-        withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 128) .-            fill $ circle (V2 120 100) 60--    produceDocImage (outFolder </> "mesh_patch_interp_bilinear.png") $ do-      let colorCycle = cycle-            [ PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0xFF 0x53 0x73 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255]-          colors = V.fromListN (4 * 4) colorCycle-      withTransformation (rotate 0.2) $-        renderMeshPatch PatchBilinear $-            generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors--    produceDocImage (outFolder </> "mesh_patch_interp_clip.png") $ do-      let colorCycle = cycle-            [ PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0xFF 0x53 0x73 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255]-          colors = V.fromListN (4 * 4) colorCycle-      withClipping (fill $ circle (V2 100 100) 75) $-        renderMeshPatch PatchBilinear $-            generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors--    produceDocImage (outFolder </> "mesh_patch_interp_bicubic.png") $ do-      let colorCycle = cycle-            [ PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0xFF 0x53 0x73 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0 0x86 0xc1 255]-          colors = V.fromListN (4 * 4) colorCycle-      renderMeshPatch PatchBicubic $ generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors--    produceDocImage (outFolder </> "mesh_patch_transp.png") $ do-      let colorCycle = cycle-            [ PixelRGBA8 0 0x86 0xc1 255-            , PixelRGBA8 0xff 0xf4 0xc1 255-            , PixelRGBA8 0xFF 0x53 0x73 127-            , PixelRGBA8 0xff 0xf4 0xc1 127-            ]-          colors = V.fromListN (1 * 4) colorCycle-      withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $-        fill $ rectangle (V2 0 70) 200 60-      renderMeshPatch PatchBicubic $-        generateLinearGrid 1 1 (V2 10 10) (V2 180 180) colors--    textExample-    textMultipleExample-    coordinateSystem-    textOnPathExample-    geometryOnPath-+{-# LANGUAGE CPP #-}
+
+#if !MIN_VERSION_base(4,8,0)
+import Control.Applicative( (<*>), (<$>) )
+#endif
+
+
+import Control.Monad( forM_ )
+import Control.Monad.ST( runST )
+import Data.Monoid( (<>) )
+import Codec.Picture
+import Codec.Picture.Types( promoteImage )
+import Graphics.Text.TrueType( loadFontFile )
+import Graphics.Rasterific
+import Graphics.Rasterific.Outline
+import Graphics.Rasterific.Texture
+import Graphics.Rasterific.Transformations
+import Graphics.Rasterific.MeshPatch
+import Graphics.Rasterific.Immediate
+import System.Directory( createDirectoryIfMissing )
+import System.FilePath( (</>) )
+import qualified Data.ByteString.Lazy as LB
+import qualified Data.Vector as V
+
+import Graphics.Rasterific.Linear( (^+^) )
+
+logo :: Int -> Bool -> Vector -> [Primitive]
+logo size inv offset =
+    toPrimitives . bezierFromPath . way $ map (^+^ offset)
+    [ (V2   0  is)
+    , (V2   0   0)
+    , (V2  is   0)
+    , (V2 is2   0)
+    , (V2 is2  is)
+    , (V2 is2 is2)
+    , (V2  is is2)
+    , (V2  0  is2)
+    , (V2  0   is)
+    ]
+  where is = fromIntegral size
+        is2 = is + is
+
+        way | inv = reverse
+            | otherwise = id
+
+backgroundColor :: PixelRGBA8
+backgroundColor = PixelRGBA8 255 255 255 255
+
+frontColor, accentColor, accent2Color :: PixelRGBA8
+frontColor = PixelRGBA8 0 0x86 0xc1 255
+accentColor = PixelRGBA8 0xff 0xf4 0xc1 255
+accent2Color = PixelRGBA8 0xFF 0x53 0x73 255
+
+frontTexture, accentTexture, accent2Texture :: Texture PixelRGBA8
+frontTexture = uniformTexture frontColor
+accentTexture = uniformTexture accentColor
+accent2Texture = uniformTexture accent2Color
+
+produceDocImageAtSize :: Int -> Int -> FilePath -> Drawing PixelRGBA8 () -> IO ()
+produceDocImageAtSize width height filename drawing = do
+    putStrLn $ "Producing " <> filename
+    writePng filename img
+    writePdf $ filename <> ".draw.pdf"
+    writeOrderPdf $ filename <> ".order.pdf"
+  where
+    img = renderDrawing width height backgroundColor
+        $ withTexture frontTexture drawing
+
+    writeOrderPdf fname =
+      LB.writeFile fname .
+        renderOrdersAtDpiToPdf width height 92 $
+          drawOrdersOfDrawing width height 92 (PixelRGBA8 0 0 0 0) $
+            withTexture frontTexture drawing
+
+    writePdf fname =
+      LB.writeFile fname .
+        renderDrawingAtDpiToPDF width height 92 $
+            withTexture frontTexture drawing
+
+produceDocImage :: FilePath -> Drawing PixelRGBA8 () -> IO ()
+produceDocImage = produceDocImageAtSize 200 200
+
+capTester :: (FilePath, Cap) -> IO ()
+capTester (filename, cap) =
+    produceDocImage filename $ do
+        stroke 30 JoinRound (cap, cap) base_stroke
+        withTexture accentTexture $
+            stroke 2 JoinRound (cap, cap) base_stroke
+  where 
+    base_stroke = line (V2 0 200) (V2 100 100)
+
+joinTester :: (FilePath, Join) -> IO ()
+joinTester (filename, join) =
+    produceDocImage filename $ do
+        stroke 30 join (CapRound, CapRound) base_stroke
+        withTexture accentTexture $
+            stroke 2 join (CapRound, CapRound) base_stroke
+  where 
+    base_stroke =
+        [ Line (V2 0 200) (V2 100 100)
+        , Line (V2 100 100) (V2 200 200)
+        ]
+
+samplerTester :: (FilePath, SamplerRepeat) -> IO ()
+samplerTester (filename, sampler) =
+    produceDocImage filename $
+       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)
+                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)
+                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in
+        withTexture (withSampler sampler $ linearGradientTexture gradDef
+                        (V2 80 100) (V2 120 110)) $
+            fill $ rectangle (V2 10 10) 180 180)
+
+outFolder :: FilePath
+outFolder = "docimages"
+
+moduleExample :: IO ()
+moduleExample = do
+  let drawColor = PixelRGBA8 0 0x86 0xc1 255
+      recColor = PixelRGBA8 0xFF 0x53 0x73 255
+      img =
+         withTexture (uniformTexture drawColor) $ do
+            fill $ circle (V2 0 0) 30
+            stroke 4 JoinRound (CapRound, CapRound) $
+                   circle (V2 400 200) 40
+            withTexture (uniformTexture recColor) .
+                fill $ rectangle (V2 100 100) 200 100
+
+  produceDocImageAtSize 400 200 (outFolder </> "module_example.png") img
+
+sansSerifFont :: FilePath
+sansSerifFont = "test_fonts/DejaVuSans.ttf"
+
+monospaceFont :: FilePath
+monospaceFont =  "test_fonts/DejaVuSansMono.ttf"
+
+textOnPathExample :: IO ()
+textOnPathExample = do
+  fontErr <- loadFontFile sansSerifFont
+  case fontErr of
+    Left err -> putStrLn err
+    Right font ->
+      let path = Path (V2 100 180) False
+                      [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]
+      in
+      produceDocImage (outFolder </> "text_on_path.png") $ do
+        stroke 3 JoinRound (CapStraight 0, CapStraight 0) path
+
+        withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $ do
+          withPathOrientation path 0 $
+            printTextAt font (PointSize 24) (V2 0 0) "Text on path"
+
+geometryOnPath :: IO ()
+geometryOnPath = do
+  fontErr <- loadFontFile sansSerifFont
+  case fontErr of
+    Left err -> putStrLn err
+    Right font ->
+      produceDocImage (outFolder </> "geometry_on_path.png") $ do
+        let path = Path (V2 100 180) False
+                        [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]
+        withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+          stroke 3 JoinRound (CapStraight 0, CapStraight 0) path
+     
+        withPathOrientation path 0 $ do
+          printTextAt font (PointSize 24) (V2 0 0) "TX"
+          fill $ rectangle (V2 (-10) (-10)) 30 20
+          fill $ rectangle (V2 45 0) 10 20
+          fill $ rectangle (V2 60 (-10)) 20 20
+          fill $ rectangle (V2 100 (-15)) 20 50
+
+textExample :: IO ()
+textExample = do
+  fontErr <- loadFontFile sansSerifFont
+  case fontErr of
+    Left err -> putStrLn err
+    Right font ->
+      produceDocImageAtSize 300 70 (outFolder </> "text_example.png")
+          . withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+                  printTextAt font (PointSize 12) (V2 20 40) "A simple text test!"
+
+textMultipleExample :: IO ()
+textMultipleExample = do
+  eitherFont1 <- loadFontFile sansSerifFont
+  eitherFont2 <- loadFontFile monospaceFont
+  case (,) <$> eitherFont1 <*> eitherFont2 of
+    Left err -> putStrLn err
+    Right (font1, font2) ->
+      produceDocImageAtSize 300 70 (outFolder </> "text_complex_example.png") $
+          let blackTexture =
+                Just . uniformTexture $ PixelRGBA8 0 0 0 255
+              redTexture =
+                Just . uniformTexture $ PixelRGBA8 255 0 0 255
+          in
+          printTextRanges (V2 20 40)
+            [ TextRange font1 (PointSize 12) "A complex " blackTexture
+            , TextRange font2 (PointSize 8) "text test" redTexture]
+
+coordinateSystem :: IO ()
+coordinateSystem = do
+    fontErr <- loadFontFile sansSerifFont
+    case fontErr of
+        Left err -> putStrLn err
+        Right font -> 
+            produceDocImage (outFolder </> "coordinate.png") $ create font
+  where
+    black = PixelRGBA8   0   0   0 255
+    stroker = stroke 4 JoinRound (CapStraight 0, CapStraight 0)
+    create font = withTexture (uniformTexture black) $ do
+        stroker $ line (V2 10 40) (V2 190 40)
+        stroker $ line (V2 40 10) (V2 40 190)
+        printTextAt font (PointSize 12) (V2 4 37) "(0,0)"
+        printTextAt font (PointSize 12) (V2 100 37) "(width, 0)"
+        printTextAt font (PointSize 12) (V2 57 190) "(0, height)"
+        fill $ Path (V2 170 30) True
+            [PathLineTo (V2 195 40), PathLineTo (V2 170 50)]
+        fill $ Path (V2 30 170) True
+            [PathLineTo (V2 40 195), PathLineTo (V2 50 170)]
+
+fillingSample :: FillMethod -> Drawing px ()
+fillingSample fillMethod = fillWithMethod fillMethod geometry where
+  geometry = transform (applyTransformation $ scale 0.35 0.4
+                                           <> translate (V2 (-80) (-180)))
+     [ Path (V2 484 499) True
+         [ PathCubicBezierCurveTo (V2 681 452) (V2 639 312) (V2 541 314)
+         , PathCubicBezierCurveTo (V2 327 337) (V2 224 562) (V2 484 499)
+         ]
+     , Path (V2 136 377) True
+         [ PathCubicBezierCurveTo (V2 244 253) (V2 424 420) (V2 357 489)
+         , PathCubicBezierCurveTo (V2 302 582) (V2 47 481) (V2 136 377)
+         ]
+     , Path (V2 340 265) True
+         [ PathCubicBezierCurveTo (V2 64 371) (V2 128 748) (V2 343 536)
+         , PathCubicBezierCurveTo (V2 668 216) (V2 17 273) (V2 367 575)
+         , PathCubicBezierCurveTo (V2 589 727) (V2 615 159) (V2 340 265)
+         ]
+     ]
+
+immediateDrawExample :: Image PixelRGBA8
+immediateDrawExample = runST $
+  runDrawContext 200 200 (PixelRGBA8 0 0 0 255) $
+    fillWithTexture FillWinding texture geometry
+  where
+    circlePrimitives = circle (V2 100 100) 50
+    geometry = strokize 4 JoinRound (CapRound, CapRound) circlePrimitives
+    texture = uniformTexture (PixelRGBA8 255 255 255 255)
+
+immediateDrawMaskExample :: Image PixelRGBA8
+immediateDrawMaskExample = runST $
+  runDrawContext 200 200 (PixelRGBA8 0 0 0 255) $
+    forM_ [1 .. 10] $ \ix ->
+       fillWithTextureAndMask FillWinding texture mask $
+           rectangle (V2 10 (ix * 18 - 5)) 180 13
+  where
+    texture = uniformTexture $ PixelRGBA8 0 0x86 0xc1 255
+    mask = sampledImageTexture
+         $ runST
+         $ runDrawContext 200 200 0
+         $ fillWithTexture FillWinding (uniformTexture 255) maskGeometry
+
+    maskGeometry = strokize 15 JoinRound (CapRound, CapRound)
+                 $ circle (V2 100 100) 80
+
+main :: IO ()
+main = do
+    let addFolder (p, v) = (outFolder </> p, v)
+    createDirectoryIfMissing True outFolder
+    moduleExample
+    mapM_ (capTester . addFolder)
+        [ ("cap_straight.png", CapStraight 0)
+        , ("cap_straight_1.png", CapStraight 1)
+        , ("cap_round.png", CapRound)
+        ]
+
+    mapM_ (joinTester . addFolder)
+        [ ("join_round.png", JoinRound)
+        , ("join_miter.png", JoinMiter 0)
+        , ("join_miter_5.png", JoinMiter 5)
+        ]
+
+    mapM_ (samplerTester . addFolder)
+        [ ("sampler_pad.png", SamplerPad)
+        , ("sampler_repeat.png", SamplerRepeat)
+        , ("sampler_reflect.png", SamplerReflect)
+        ]
+
+    writePng (outFolder </> "immediate_fill.png") immediateDrawExample
+    writePng (outFolder </> "immediate_mask.png") immediateDrawMaskExample 
+
+    produceDocImage (outFolder </> "fill_circle.png") $
+        fill $ circle (V2 100 100) 75 
+
+    produceDocImage (outFolder </> "fill_ellipse.png") $
+        fill $ ellipse (V2 100 100) 75 30
+
+    produceDocImage (outFolder </> "stroke_circle.png") $
+        stroke 5 JoinRound (CapRound, CapRound) $ circle (V2 100 100) 75 
+
+    produceDocImage (outFolder </> "dashed_stroke.png") $
+        dashedStroke [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $
+            line (V2 0 100) (V2 200 100)
+
+    produceDocImage (outFolder </> "dashed_stroke_with_offset.png") $
+        dashedStrokeWithOffset 3 [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $
+            line (V2 0 100) (V2 200 100)
+
+    produceDocImage (outFolder </> "fill_rect.png") $
+        fill $ rectangle (V2 30 30) 150 100
+
+    produceDocImage (outFolder </> "with_texture.png") $
+      withTexture frontTexture $ do
+          fill $ circle (V2 50 50) 20
+          fill $ circle (V2 100 100) 20
+          withTexture accent2Texture $
+               fill $ circle (V2 150 150) 20
+
+    produceDocImage (outFolder </> "strokize_path.png") $
+      stroke 3 (JoinMiter 0) (CapStraight 0, CapStraight 0) $
+          strokize 40 JoinRound (CapRound, CapRound) $
+            CubicBezier (V2  40 160) (V2 40   40)
+                        (V2 160  40) (V2 160 160)
+
+    produceDocImage (outFolder </> "strokize_dashed_path.png") $
+      mapM_ (stroke 3 (JoinMiter 0) (CapStraight 0, CapStraight 0)) $
+          dashedStrokize 0 [10, 5]
+                         40 JoinRound (CapStraight 0, CapStraight 0)
+            [CubicBezier (V2  40 160) (V2 40   40)
+                         (V2 160  40) (V2 160 160)]
+
+    produceDocImage (outFolder </> "with_clipping.png") $
+      withClipping (fill $ circle (V2 100 100) 75) $
+          mapM_ (stroke 7 JoinRound (CapRound, CapRound))
+            [line (V2 0 yf) (V2 200 (yf + 10)) 
+                           | y <- [5 :: Int, 17 .. 200]
+                           , let yf = fromIntegral y ]
+
+    {-produceDocImage (outFolder </> "clip_compose.png") $-}
+
+    produceDocImage (outFolder </> "stroke_line.png") $
+      stroke 17 JoinRound (CapRound, CapRound) $
+        line (V2 10 10) (V2 180 170)
+
+    produceDocImage (outFolder </> "linear_gradient.png") $
+       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)
+                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)
+                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in
+        withTexture (linearGradientTexture gradDef (V2 40 40) (V2 130 130)) $
+            fill $ circle (V2 100 100) 100)
+
+    produceDocImage (outFolder </> "radial_gradient.png") $
+       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)
+                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)
+                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in
+        withTexture (radialGradientTexture gradDef (V2 100 100) 75) $
+            fill $ circle (V2 100 100) 100)
+
+    produceDocImage (outFolder </> "radial_gradient_focus.png") $
+       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)
+                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)
+                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in
+        withTexture (radialGradientWithFocusTexture gradDef (V2 100 100) 75 (V2 70 70)) $
+            fill $ circle (V2 100 100) 100)
+
+    produceDocImage (outFolder </> "sampler_pad.png") $
+       (let gradDef = [(0, PixelRGBA8 0 0x86 0xc1 255)
+                      ,(0.5, PixelRGBA8 0xff 0xf4 0xc1 255)
+                      ,(1, PixelRGBA8 0xFF 0x53 0x73 255)] in
+        withTexture (linearGradientTexture gradDef (V2 80 100) (V2 120 110)) $
+            fill $ rectangle (V2 10 10) 180 180)
+
+    produceDocImage (outFolder </> "logo.png") $ do
+      let colorCycle = cycle
+            [ PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xDf 0xD4 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255]
+          colors = V.fromListN (4 * 4) colorCycle
+          mesh = generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors
+      withTexture (transformTexture (scale 0.7 0.7 <> rotateCenter (-0.4) (V2 100 100)) $
+                    meshPatchTexture PatchBicubic mesh) $
+        fill $ logo 80 False (V2 20 20) ++ 
+               logo 40 True (V2 40 40)
+
+    produceDocImage (outFolder </> "cubic_bezier.png") $
+        stroke 5 JoinRound (CapRound, CapRound) $
+            CubicBezier (V2 0 10) (V2 205 250)
+                        (V2 (-10) 250) (V2 160 35)
+
+    produceDocImage (outFolder </> "quadratic_bezier.png") $
+        fill [ Bezier (V2 10 10) (V2 200 50) (V2 200 100)
+             , Bezier (V2 200 100) (V2 150 200) (V2 120 175)
+             , Bezier (V2 120 175) (V2 30 100) (V2 10 10)]
+
+    produceDocImage (outFolder </> "simple_line.png") $
+        fill [ Line (V2 10 10) (V2 190 10)
+             , Line (V2 190 10) (V2 95 170)
+             , Line (V2 95 170) (V2 10 10) ]
+
+    produceDocImage (outFolder </> "primitive_mixed.png") $
+        fill
+            [ toPrim $ CubicBezier (V2 50 20) (V2 90 60)
+                                   (V2  5 100) (V2 50 140)
+            , toPrim $ Line (V2 50 140) (V2 120 80)
+            , toPrim $ Line (V2 120 80) (V2 50 20) ]
+
+    produceDocImage (outFolder </> "path_example.png") $
+       fill $ Path (V2 50 20) True
+          [ PathCubicBezierCurveTo (V2 90 60) (V2  5 100) (V2 50 140)
+          , PathLineTo (V2 120 80) ]
+
+    produceDocImage (outFolder </> "stroke_polyline.png") $
+        stroke 4 JoinRound (CapRound, CapRound) $
+            polyline [V2 10 10, V2 100 70, V2 190 190]
+
+    produceDocImage (outFolder </> "fill_polygon.png") $
+        fill $ polygon [V2 30 30, V2 100 70, V2 80 170]
+
+    produceDocImage  (outFolder </> "fill_roundedRectangle.png") $
+        fill $ roundedRectangle (V2 10 10) 150 150 20 10
+
+    produceDocImage  (outFolder </> "stroke_roundedRectangle.png") $
+        stroke 4 JoinRound (CapRound, CapRound) $
+            roundedRectangle (V2 10 10) 150 150 20 10
+
+    produceDocImage (outFolder </> "fill_evenodd.png") $
+        fillingSample FillEvenOdd
+
+    produceDocImage (outFolder </> "fill_winding.png") $
+        fillingSample FillWinding
+
+    produceDocImage (outFolder </> "transform_rotate.png") $
+        fill . transform (applyTransformation $ rotate 0.2)
+             $ rectangle (V2 40 40) 120 120
+
+    produceDocImage (outFolder </> "transform_rotate_center.png") $
+        fill . transform (applyTransformation $ rotateCenter 0.2 (V2 200 200))
+             $ rectangle (V2 40 40) 120 120
+
+    produceDocImage (outFolder </> "transform_translate.png") $
+        fill . transform (applyTransformation $ translate (V2 100 100))
+             $ rectangle (V2 40 40) 40 40
+
+    produceDocImage (outFolder </> "transform_scale.png") $
+        fill . transform (applyTransformation $ scale 2 2)
+             $ rectangle (V2 40 40) 40 40
+
+    produceDocImage (outFolder </> "transform_skewx.png") $
+        fill . transform (applyTransformation $ skewX 0.3)
+             $ rectangle (V2 50 50) 80 80
+
+    produceDocImage (outFolder </> "transform_skewy.png") $
+        fill . transform (applyTransformation $ skewY 0.3)
+             $ rectangle (V2 50 50) 80 80
+
+    Right (ImageRGB8 img) <- readImage "avatar.png"
+    let textureImage = promoteImage img
+    produceDocImage (outFolder </> "sampled_texture_repeat.png") $
+        withTexture (withSampler SamplerRepeat $
+                        sampledImageTexture textureImage) $
+            fill $ rectangle (V2 0 0) 200 200
+
+    produceDocImage (outFolder </> "image_simple.png") $
+        drawImage textureImage 0 (V2 30 30)
+
+    produceDocImage (outFolder </> "image_resize.png") $
+        drawImageAtSize textureImage 2 (V2 30 30) 128 128
+
+    produceDocImage (outFolder </> "sampled_texture_reflect.png") $
+        withTexture (withSampler SamplerReflect $
+                        sampledImageTexture textureImage) $
+            fill $ rectangle (V2 0 0) 200 200
+
+    produceDocImage (outFolder </> "sampled_texture_pad.png") $
+        withTexture (sampledImageTexture textureImage) $
+            fill $ rectangle (V2 0 0) 200 200
+
+    produceDocImage (outFolder </> "sampled_texture_rotate.png") $
+        withTexture (withSampler SamplerRepeat $
+                    transformTexture (rotateCenter 1 (V2 0 0))
+                    $ sampledImageTexture textureImage) $
+            fill $ rectangle (V2 0 0) 200 200
+
+    produceDocImage (outFolder </> "sampled_texture_scaled.png") $
+        withTexture (withSampler SamplerRepeat $
+                    transformTexture (rotateCenter 1 (V2 0 0) <> 
+                                      scale 0.5 0.25)
+                    $ sampledImageTexture textureImage) $
+            fill $ rectangle (V2 0 0) 200 200
+
+    produceDocImage (outFolder </> "group_opacity.png") $ do
+        withTexture accent2Texture $
+            stroke 3 JoinRound (CapRound, CapRound) $
+                line (V2 0 100) (V2 200 100)
+
+        withGroupOpacity 128 $ do
+           withTexture frontTexture . fill $ circle (V2 70 100) 60
+           withTexture accentTexture . fill $ circle (V2 120 100) 60
+
+    produceDocImage (outFolder </> "pattern_texture.png") $
+        let pattern =
+              patternTexture 40 40 96 accent2Color .
+                withTexture frontTexture $
+                  fill $ circle (V2 20 20) 13
+        in
+        withTexture pattern $
+          fill $ roundedRectangle (V2 20 20) 160 160 20 20
+
+    produceDocImage (outFolder </> "item_opacity.png") $ do
+        withTexture accent2Texture $
+            stroke 3 JoinRound (CapRound, CapRound) $
+                line (V2 0 100) (V2 200 100)
+
+        withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 128) .
+            fill $ circle (V2 70 100) 60
+        withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 128) .
+            fill $ circle (V2 120 100) 60
+
+    produceDocImage (outFolder </> "mesh_patch_interp_bilinear.png") $ do
+      let colorCycle = cycle
+            [ PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0xFF 0x53 0x73 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255]
+          colors = V.fromListN (4 * 4) colorCycle
+      withTransformation (rotate 0.2) $
+        renderMeshPatch PatchBilinear $
+            generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors
+
+    produceDocImage (outFolder </> "mesh_patch_interp_clip.png") $ do
+      let colorCycle = cycle
+            [ PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0xFF 0x53 0x73 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255]
+          colors = V.fromListN (4 * 4) colorCycle
+      withClipping (fill $ circle (V2 100 100) 75) $
+        renderMeshPatch PatchBilinear $
+            generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors
+
+    produceDocImage (outFolder </> "mesh_patch_interp_bicubic.png") $ do
+      let colorCycle = cycle
+            [ PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0xFF 0x53 0x73 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0 0x86 0xc1 255]
+          colors = V.fromListN (4 * 4) colorCycle
+      renderMeshPatch PatchBicubic $ generateLinearGrid 3 3 (V2 10 10) (V2 60 60) colors
+
+    produceDocImage (outFolder </> "mesh_patch_transp.png") $ do
+      let colorCycle = cycle
+            [ PixelRGBA8 0 0x86 0xc1 255
+            , PixelRGBA8 0xff 0xf4 0xc1 255
+            , PixelRGBA8 0xFF 0x53 0x73 127
+            , PixelRGBA8 0xff 0xf4 0xc1 127
+            ]
+          colors = V.fromListN (1 * 4) colorCycle
+      withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+        fill $ rectangle (V2 0 70) 200 60
+      renderMeshPatch PatchBicubic $
+        generateLinearGrid 1 1 (V2 10 10) (V2 180 180) colors
+
+    textExample
+    textMultipleExample
+    coordinateSystem
+    textOnPathExample
+    geometryOnPath
+
src/Graphics/Rasterific.hs view
@@ -1,823 +1,832 @@-{-# LANGUAGE ScopedTypeVariables #-}-{-# LANGUAGE RankNTypes #-}-{-# LANGUAGE FlexibleContexts #-}-{-# LANGUAGE TypeFamilies #-}-{-# LANGUAGE TypeSynonymInstances #-}-{-# LANGUAGE FlexibleInstances #-}-{-# LANGUAGE ConstraintKinds #-}-{-# LANGUAGE CPP #-}---- | Main module of Rasterific, an Haskell rasterization engine.------ Creating an image is rather simple, here is a simple example--- of a drawing and saving it in a PNG file:------ > import Codec.Picture( PixelRGBA8( .. ), writePng )--- > import Graphics.Rasterific--- > import Graphics.Rasterific.Texture--- >--- > main :: IO ()--- > main = do--- >   let white = PixelRGBA8 255 255 255 255--- >       drawColor = PixelRGBA8 0 0x86 0xc1 255--- >       recColor = PixelRGBA8 0xFF 0x53 0x73 255--- >       img = renderDrawing 400 200 white $--- >          withTexture (uniformTexture drawColor) $ do--- >             fill $ circle (V2 0 0) 30--- >             stroke 4 JoinRound (CapRound, CapRound) $--- >                    circle (V2 400 200) 40--- >             withTexture (uniformTexture recColor) .--- >                    fill $ rectangle (V2 100 100) 200 100--- >--- >   writePng "yourimage.png" img------ <<docimages/module_example.png>>------ The coordinate system is the picture classic one, with the origin in--- the upper left corner; with the y axis growing to the bottom and the--- x axis growing to the right:------ <<docimages/coordinate.png>>----module Graphics.Rasterific-    (-      -- * Rasterization command-      -- ** Filling-      fill-    , fillWithMethod-    , renderMeshPatch-      -- ** Stroking-    , stroke-    , dashedStroke-    , dashedStrokeWithOffset-      -- ** Text rendering-    , printTextAt-    , printTextRanges-      -- ** Texturing-    , withTexture-    , withClipping-    , withGroupOpacity-      -- ** Transformations-    , withTransformation-    , withPathOrientation-    , TextRange( .. )-    , PointSize( .. )--      -- * Generating images-    , ModulablePixel-    , RenderablePixel-    , renderDrawing-    , renderDrawingAtDpi-    , renderDrawingAtDpiToPDF-    , renderOrdersAtDpiToPdf -    , pathToPrimitives--      -- * Rasterization types-    , Texture-    , Drawing-    , Modulable--      -- * Geometry description-    , V2( .. )-    , Point-    , Vector-    , CubicBezier( .. )-    , Line( .. )-    , Bezier( .. )-    , Primitive( .. )-    , Path( .. )-    , PathCommand( .. )--      -- * Generic geometry description-    , Primitivable( .. )-    , Geometry( .. )--      -- * Generic geometry manipulation-    , Transformable( .. )-    , PointFoldable( .. )-    , PlaneBoundable( .. )-    , PlaneBound( .. )-    , boundWidth-    , boundHeight-    , boundLowerLeftCorner--      -- * Helpers-      -- ** line-    , line-      -- ** Rectangle-    , rectangle-    , roundedRectangle-      -- ** Circles-    , circle-    , ellipse-      -- ** Polygons-    , polyline-    , polygon-      -- ** Images-    , drawImageAtSize-    , drawImage-    , cacheDrawing--      -- ** Geometry Helpers-    , clip-    , bezierFromPath-    , lineFromPath-    , cubicBezierFromPath-    , firstTangeantOf-    , lastTangeantOf-    , firstPointOf-    , lastPointOf--      -- * Rasterization control-    , Join( .. )-    , Cap( .. )-    , SamplerRepeat( .. )-    , FillMethod( .. )-    , PatchInterpolation( .. )-    , DashPattern-    , drawOrdersOfDrawing--      -- * Debugging helper-    , dumpDrawing-    ) where--#if !MIN_VERSION_base(4,8,0)-import Control.Applicative( (<$>) )-import Data.Foldable( foldMap )-import Data.Monoid( Monoid( .. ) )-#endif--import Data.Monoid( (<>) )--import Control.Monad.Free( Free( .. ), liftF )-import Control.Monad.Free.Church( fromF )-import Control.Monad.ST( ST, runST )-import Control.Monad.State( modify, execState )-import Data.Maybe( fromMaybe )-import Codec.Picture.Types( Image( .. )-                          , Pixel( .. )-                          , PixelRGBA8-                          , pixelMapXY )--import qualified Data.ByteString.Lazy as LB-import qualified Data.Vector as V--import Graphics.Rasterific.Compositor-import Graphics.Rasterific.Linear( V2( .. ), (^+^), (^-^) )-import Graphics.Rasterific.Rasterize-import Graphics.Rasterific.MicroPdf-{-import Graphics.Rasterific.Texture-}-import Graphics.Rasterific.ComplexPrimitive-import Graphics.Rasterific.Types-import Graphics.Rasterific.Line-import Graphics.Rasterific.QuadraticBezier-import Graphics.Rasterific.CubicBezier-import Graphics.Rasterific.StrokeInternal-import Graphics.Rasterific.Transformations-import Graphics.Rasterific.PlaneBoundable-import Graphics.Rasterific.Immediate-import Graphics.Rasterific.PathWalker-import Graphics.Rasterific.Command-import Graphics.Rasterific.PatchTypes-import Graphics.Rasterific.Patch-import Graphics.Rasterific.MeshPatch-{-import Graphics.Rasterific.TensorPatch-}--import Graphics.Text.TrueType( Font-                             , Dpi-                             , PointSize( .. )-                             )--{-import Debug.Trace-}-{-import Text.Printf-}-------------------------------------------------------    Free Monad DSL section----------------------------------------------------- | Define the texture applyied to all the children--- draw call.------ > withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 255) $ do--- >     fill $ circle (V2 50 50) 20--- >     fill $ circle (V2 100 100) 20--- >     withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255)--- >          $ circle (V2 150 150) 20------ <<docimages/with_texture.png>>----withTexture :: Texture px -> Drawing px () -> Drawing px ()-withTexture texture subActions =-    liftF $ SetTexture texture subActions ()---- | Will render the whole subaction with a given group opacity, after--- each element has been rendered. That means that completly opaque--- overlapping shapes will be rendered transparently, not one after--- another.------ > withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255) $--- >     stroke 3 JoinRound (CapRound, CapRound) $--- >         line (V2 0 100) (V2 200 100)--- >--- > withGroupOpacity 128 $ do--- >    withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 255) .--- >       fill $ circle (V2 70 100) 60--- >    withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 255) .--- >       fill $ circle (V2 120 100) 60------ <<docimages/group_opacity.png>>------ To be compared to the item opacity------ > withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255) $--- >     stroke 3 JoinRound (CapRound, CapRound) $--- >         line (V2 0 100) (V2 200 100)--- > withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 128) .--- >    fill $ circle (V2 70 100) 60--- > withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 128) .--- >    fill $ circle (V2 120 100) 60------ <<docimages/item_opacity.png>>-withGroupOpacity :: PixelBaseComponent px -> Drawing px ()-> Drawing px ()-withGroupOpacity opa sub = liftF $ WithGlobalOpacity opa sub ()---- | Draw all the sub drawing commands using a transformation.-withTransformation :: Transformation -> Drawing px () -> Drawing px ()-withTransformation trans sub =-    liftF $ WithTransform trans sub ()---- | This command allows you to draw primitives on a given curve,--- for example, you can draw text on a curve:------ > let path = Path (V2 100 180) False--- >                 [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)] in--- > stroke 3 JoinRound (CapStraight 0, CapStraight 0) path--- > withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $--- >   withPathOrientation path 0 $--- >     printTextAt font (PointSize 24) (V2 0 0) "Text on path"------ <<docimages/text_on_path.png>>------ You can note that the position of the baseline match the size of the--- characters.------ You are not limited to text drawing while using this function,--- you can draw arbitrary geometry like in the following example:------ > let path = Path (V2 100 180) False--- >                 [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]--- > withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $--- >   stroke 3 JoinRound (CapStraight 0, CapStraight 0) path--- > --- > withPathOrientation path 0 $ do--- >   printTextAt font (PointSize 24) (V2 0 0) "TX"--- >   fill $ rectangle (V2 (-10) (-10)) 30 20--- >   fill $ rectangle (V2 45 0) 10 20--- >   fill $ rectangle (V2 60 (-10)) 20 20--- >   fill $ rectangle (V2 100 (-15)) 20 50------ <<docimages/geometry_on_path.png>>----withPathOrientation :: Path            -- ^ Path directing the orientation.-                    -> Float           -- ^ Basline Y axis position, used to align text properly.-                    -> Drawing px ()   -- ^ The sub drawings.-                    -> Drawing px ()-withPathOrientation path p sub =-    liftF $ WithPathOrientation path p sub ()---- | Fill some geometry. The geometry should be "looping",--- ie. the last point of the last primitive should--- be equal to the first point of the first primitive.------ The primitive should be connected.------ > fill $ circle (V2 100 100) 75------ <<docimages/fill_circle.png>>----fill :: Geometry geom => geom -> Drawing px ()-fill prims = liftF $ Fill FillWinding (toPrimitives prims) ()---- | This function let you choose how to fill the primitives--- in case of self intersection. See `FillMethod` documentation--- for more information.-fillWithMethod :: Geometry geom-               => FillMethod -> geom -> Drawing px ()-fillWithMethod method prims =-    liftF $ Fill method (toPrimitives prims) ()---- | Draw some geometry using a clipping path.------ > withClipping (fill $ circle (V2 100 100) 75) $--- >     mapM_ (stroke 7 JoinRound (CapRound, CapRound))--- >       [line (V2 0 yf) (V2 200 (yf + 10))--- >                      | y <- [5 :: Int, 17 .. 200]--- >                      , let yf = fromIntegral y ]------ <<docimages/with_clipping.png>>----withClipping-    :: (forall innerPixel. Drawing innerPixel ()) -- ^ The clipping path-    -> Drawing px () -- ^ The actual geometry to clip-    -> Drawing px ()-withClipping clipPath drawing =-    liftF $ WithCliping clipPath drawing ()---- | Will stroke geometry with a given stroke width.--- The elements should be connected------ > stroke 5 JoinRound (CapRound, CapRound) $ circle (V2 100 100) 75------ <<docimages/stroke_circle.png>>----stroke :: (Geometry geom)-       => Float       -- ^ Stroke width-       -> Join        -- ^ Which kind of join will be used-       -> (Cap, Cap)  -- ^ Start and end capping.-       -> geom        -- ^ List of elements to render-       -> Drawing px ()-stroke width join caping prims =-    liftF $ Stroke width join caping (toPrimitives prims) ()---- | Draw a string at a given position.--- Text printing imply loading a font, there is no default--- font (yet). Below an example of font rendering using a--- font installed on Microsoft Windows.------ > import Graphics.Text.TrueType( loadFontFile )--- > import Codec.Picture( PixelRGBA8( .. ), writePng )--- > import Graphics.Rasterific--- > import Graphics.Rasterific.Texture--- >--- > main :: IO ()--- > main = do--- >   fontErr <- loadFontFile "test_fonts/DejaVuSans.ttf"--- >   case fontErr of--- >     Left err -> putStrLn err--- >     Right font ->--- >       writePng "text_example.png" .--- >           renderDrawing 300 70 (PixelRGBA8 255 255 255 255)--- >               . withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $--- >                       printTextAt font (PointSize 12) (V2 20 40)--- >                            "A simple text test!"------ <<docimages/text_example.png>>------ You can use any texture, like a gradient while rendering text.----printTextAt :: Font            -- ^ Drawing font-            -> PointSize       -- ^ font Point size-            -> Point           -- ^ Drawing starting point (base line)-            -> String          -- ^ String to print-            -> Drawing px ()-printTextAt font pointSize point string =-    liftF $ TextFill point [description] ()-  where-    description = TextRange-        { _textFont    = font-        , _textSize    = pointSize-        , _text        = string-        , _textTexture = Nothing-        }---- | Render a mesh patch as an object. Warning, there is--- no antialiasing on mesh patch objects!-renderMeshPatch :: PatchInterpolation -> MeshPatch px -> Drawing px ()-renderMeshPatch i mesh = liftF $ MeshPatchRender i mesh ()---- | Print complex text, using different texture font and--- point size for different parts of the text.------ > let blackTexture =--- >       Just . uniformTexture $ PixelRGBA8 0 0 0 255--- >     redTexture =--- >       Just . uniformTexture $ PixelRGBA8 255 0 0 255--- > in--- > printTextRanges (V2 20 40)--- >   [ TextRange font1 (PointSize 12) "A complex " blackTexture--- >   , TextRange font2 (PointSize 8) "text test" redTexture]------ <<docimages/text_complex_example.png>>----printTextRanges :: Point            -- ^ Starting point of the base line-                -> [TextRange px]   -- ^ Ranges description to be printed-                -> Drawing px ()-printTextRanges point ranges = liftF $ TextFill point ranges ()--data RenderContext px = RenderContext-    { currentClip           :: Maybe (Texture (PixelBaseComponent px))-    , currentTexture        :: Texture px-    , currentTransformation :: Maybe (Transformation, Transformation)-    }---- | Function to call in order to start the image creation.--- Tested pixels type are PixelRGBA8 and Pixel8, pixel types--- in other colorspace will probably produce weird results.--- Default DPI is 96-renderDrawing-    :: forall px . (RenderablePixel px)-    => Int -- ^ Rendering width-    -> Int -- ^ Rendering height-    -> px  -- ^ Background color-    -> Drawing px () -- ^ Rendering action-    -> Image px-renderDrawing width height = renderDrawingAtDpi width height 96--renderOrdersAtDpiToPdf -    :: Int -- ^ Rendering width-    -> Int -- ^ Rendering height-    -> Dpi -- ^ Current DPI used for text rendering.-    -> [DrawOrder PixelRGBA8]  -- ^ Drawing Orders-    -> LB.ByteString-renderOrdersAtDpiToPdf w h dpi =-  renderOrdersToPdf renderer w h dpi-    where-      renderer :: forall px . RenderablePixel px => Drawing px () -> [DrawOrder px]-      renderer = drawOrdersOfDrawing w h dpi emptyPx--renderDrawingAtDpiToPDF-    :: Int -- ^ Rendering width-    -> Int -- ^ Rendering height-    -> Dpi -- ^ Current DPI used for text rendering.-    -> Drawing PixelRGBA8 () -- ^ Rendering action-    -> LB.ByteString-renderDrawingAtDpiToPDF w h dpi =-  renderDrawingToPdf renderer w h dpi-    where-      renderer :: forall px . RenderablePixel px => Drawing px () -> [DrawOrder px]-      renderer = drawOrdersOfDrawing w h dpi emptyPx---- | Function to call in order to start the image creation.--- Tested pixels type are PixelRGBA8 and Pixel8, pixel types--- in other colorspace will probably produce weird results.-renderDrawingAtDpi-    :: forall px . (RenderablePixel px)-    => Int -- ^ Rendering width-    -> Int -- ^ Rendering height-    -> Dpi -- ^ Current DPI used for text rendering.-    -> px  -- ^ Background color-    -> Drawing px () -- ^ Rendering action-    -> Image px-renderDrawingAtDpi width height dpi background drawing =-    runST $ runDrawContext width height background-          $ mapM_ fillOrder-          $ drawOrdersOfDrawing width height dpi background drawing--cacheOrders :: forall px. (RenderablePixel px)-            => Maybe (Image px -> ImageTransformer px) -> [DrawOrder px] -> Drawing px ()-cacheOrders imageFilter orders = case imageFilter of-    Nothing -> drawImage resultImage 0 cornerUpperLeft-    Just f -> drawImage (pixelMapXY (f resultImage) resultImage) 0 cornerUpperLeft-  where-   PlaneBound mini maxi = foldMap planeBounds orders-   cornerUpperLeftInt = floor <$> mini :: V2 Int-   cornerUpperLeft = fromIntegral <$> cornerUpperLeftInt--   V2 width height = maxi ^-^ cornerUpperLeft ^+^ V2 1 1-   -   shiftOrder order@DrawOrder { _orderPrimitives = prims } =-       order { _orderPrimitives = fmap (transform (^-^ cornerUpperLeft)) <$> prims -             , _orderTexture =-                 WithTextureTransform (translate cornerUpperLeft) $ _orderTexture order-             }-   -   resultImage =-     runST $ runDrawContext (ceiling width) (ceiling height) emptyPx-           $ mapM_ (fillOrder . shiftOrder) orders---- | This function perform an optimisation, it will render a drawing--- to an image interanlly and create a new order to render this image--- instead of the geometry, effectively cuting the geometry generation--- part.------ It can save execution time when drawing complex elements multiple--- times.-cacheDrawing-    :: forall px . (RenderablePixel px)-    => Int -- ^ Max rendering width-    -> Int -- ^ Max rendering height-    -> Dpi-    -> Drawing px ()-    -> Drawing px ()-cacheDrawing maxWidth maxHeight dpi sub =-  cacheOrders Nothing $ drawOrdersOfDrawing maxWidth maxHeight dpi emptyPx sub--preComputeTexture :: (RenderablePixel px)-                  => Int -> Int -> Texture px -> Texture px-preComputeTexture w h = go where-  go :: RenderablePixel px => Texture px -> Texture px-  go t = case t of-    SolidTexture _ -> t-    LinearGradientTexture _ _ -> t-    RadialGradientTexture _ _ _ -> t-    RadialGradientWithFocusTexture _ _ _ _ -> t-    WithSampler s sub -> WithSampler s $ go sub-    WithTextureTransform trans sub -> WithTextureTransform trans $ go sub-    SampledTexture _ -> t-    RawTexture _ -> t-    ShaderTexture _ -> t-    ModulateTexture t1 t2 -> ModulateTexture (go t1) (go t2)-    PatternTexture _ _ _ _ _ -> t-    AlphaModulateTexture i m -> AlphaModulateTexture (go i) (go m)-    MeshPatchTexture i m ->-        RawTexture $ renderDrawing w h emptyPx $ renderMeshPatch i m---- | Transform a drawing into a serie of low-level drawing orders.-drawOrdersOfDrawing-    :: forall px . (RenderablePixel px) -    => Int -- ^ Rendering width-    -> Int -- ^ Rendering height-    -> Dpi -- ^ Current assumed DPI-    -> px  -- ^ Background color-    -> Drawing px () -- ^ Rendering action-    -> [DrawOrder px]-drawOrdersOfDrawing width height dpi background drawing =-    go initialContext (fromF drawing) []-  where-    initialContext = RenderContext Nothing stupidDefaultTexture Nothing-    clipBackground = emptyValue :: PixelBaseComponent px-    clipForeground = fullValue :: PixelBaseComponent px--    clipRender =-      renderDrawing width height clipBackground-            . withTexture (SolidTexture clipForeground)--    subRender :: (forall s. DrawContext (ST s) px ()) -> Image px-    subRender act =-      runST $ runDrawContext width height background act--    textureOf ctxt@RenderContext { currentTransformation = Just (_, t) } =-        WithTextureTransform t $ currentTexture ctxt-    textureOf ctxt = currentTexture ctxt--    geometryOf :: Transformable a => RenderContext px -> a -> a-    geometryOf RenderContext { currentTransformation = Just (trans, _) } =-        transform (applyTransformation trans)-    geometryOf _ = id--    geometryOfO RenderContext { currentTransformation = Just (trans, _) } =-        transformOrder (applyTransformation trans)-    geometryOfO _ = id--    stupidDefaultTexture =-        SolidTexture $ colorMap (const clipBackground) background--    go :: RenderContext px -> Free (DrawCommand px) () -> [DrawOrder px]-       -> [DrawOrder px]-    go _ (Pure ()) rest = rest-    go ctxt (Free (WithGlobalOpacity opa sub next)) rest =-        go ctxt (Free (WithImageEffect opacifier sub next)) rest-      where -        -- Todo: a colorMapWithAlpha is really needed in JP API.-        opacifier _ _ _ px = mixWithAlpha ignore alphaModulate px px-        ignore _ _ a = a-        alphaModulate _ v = opa `modulate` v--    go ctxt (Free (WithImageEffect effect sub next)) rest =-        go freeContext (fromF cached) after-      where-        cached = cacheOrders (Just effect) $ go ctxt (fromF sub) []-        after = go ctxt next rest-        freeContext = ctxt { currentClip = Nothing, currentTransformation = Nothing }---    go ctxt (Free (WithPathOrientation path base sub next)) rest = final where-      final = orders <> go ctxt next rest-      images = go ctxt (fromF sub) []--      drawer trans _ order =-        modify (transformOrder (applyTransformation trans) order :)--      orders = reverse $ execState (drawOrdersOnPath drawer 0 base path images) []--    go ctxt (Free (WithTransform trans sub next)) rest = final where-      trans'-        | Just (t, _) <- currentTransformation ctxt = t <> trans-        | otherwise = trans-      invTrans = fromMaybe mempty $ inverseTransformation trans'-      after = go ctxt next rest-      subContext =-          ctxt { currentTransformation = Just (trans', invTrans) }--      final = go subContext (fromF sub) after--    go ctxt (Free (CustomRender cust next)) rest = order : after where-      after = go ctxt next rest-      order = DrawOrder -            { _orderPrimitives = []-            , _orderTexture    = textureOf ctxt-            , _orderFillMethod = FillWinding-            , _orderMask       = currentClip ctxt-            , _orderDirect     = cust-            }--    go ctxt (Free (MeshPatchRender i mesh next)) rest = order : after where-      after = go ctxt next rest-      rendering :: DrawContext (ST s) px ()-      rendering = case i of-        PatchBilinear -> mapM_ rasterizeCoonPatch $ coonPatchesOf $ geometryOf ctxt opaqueMesh -        PatchBicubic ->-            mapM_ rasterizeCoonPatch-                . cubicCoonPatchesOf -                $ calculateMeshColorDerivative $ geometryOf ctxt opaqueMesh --      hasTransparency =-          V.any ((/= fullValue) . pixelOpacity) $ _meshColors mesh--      opacifier px = mixWithAlpha (\_ _ a -> a) (\_ _ -> fullValue) px px--      opaqueMesh = opacifier <$> mesh-      transparencyMesh = pixelOpacity <$> mesh--      clipPath-        | not hasTransparency = currentClip ctxt-        | otherwise =-            let newMask :: Image (PixelBaseComponent (PixelBaseComponent px))-                newMask = clipRender $ renderMeshPatch i transparencyMesh in-            case currentClip ctxt of-              Nothing -> Just $ RawTexture newMask-              Just v -> Just $ ModulateTexture v (RawTexture newMask)--      order = case clipPath of-        -- Good, we can directly render on the final canvas-        Nothing -> DrawOrder -            { _orderPrimitives = []-            , _orderTexture    = textureOf ctxt-            , _orderFillMethod = FillWinding-            , _orderMask       = clipPath-            , _orderDirect     = rendering-            }-        Just c -> DrawOrder-            { _orderPrimitives = [geometryOf ctxt $ rectangle (V2 0 0) (fromIntegral width) (fromIntegral height)]-            , _orderTexture    = AlphaModulateTexture (RawTexture $ subRender rendering) c-            , _orderFillMethod = FillWinding-            , _orderMask       = Nothing-            , _orderDirect     = return ()-            }--    go ctxt (Free (Fill method prims next)) rest = order : after where-      after = go ctxt next rest-      order = DrawOrder -            { _orderPrimitives = [geometryOf ctxt prims]-            , _orderTexture    = textureOf ctxt-            , _orderFillMethod = method-            , _orderMask       = currentClip ctxt-            , _orderDirect     = return ()-            }--    go ctxt (Free (Stroke w j cap prims next)) rest =-        go ctxt (Free $ Fill FillWinding prim' next) rest-            where prim' = listOfContainer $ strokize w j cap prims--    go ctxt (Free (SetTexture tx sub next)) rest =-        go (ctxt { currentTexture = preComputeTexture width height tx }) (fromF sub) $-            go ctxt next rest--    go ctxt (Free (DashedStroke o d w j cap prims next)) rest =-        foldr recurse after $ dashedStrokize o d w j cap prims-      where-        after = go ctxt next rest-        recurse sub =-            go ctxt (liftF $ Fill FillWinding sub ())--    go ctxt (Free (TextFill p descriptions next)) rest = calls <> go ctxt next rest where-      calls =-        geometryOfO ctxt <$> textToDrawOrders dpi (currentTexture ctxt) p descriptions--    go ctxt (Free (WithCliping clipPath path next)) rest =-        go (ctxt { currentClip = newModuler }) (fromF path) $-            go ctxt next rest-      where-        modulationTexture :: Texture (PixelBaseComponent px)-        modulationTexture = RawTexture $ clipRender clipPath--        newModuler = Just . subModuler $ currentClip ctxt--        subModuler Nothing = modulationTexture-        subModuler (Just v) =-            ModulateTexture v modulationTexture---- | With stroke geometry with a given stroke width, using--- a dash pattern.------ > dashedStroke [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $--- >     line (V2 0 100) (V2 200 100)------ <<docimages/dashed_stroke.png>>----dashedStroke-    :: Geometry geom-    => DashPattern -- ^ Dashing pattern to use for stroking-    -> Float       -- ^ Stroke width-    -> Join        -- ^ Which kind of join will be used-    -> (Cap, Cap)  -- ^ Start and end capping.-    -> geom        -- ^ List of elements to render-    -> Drawing px ()-dashedStroke = dashedStrokeWithOffset 0.0---- | With stroke geometry with a given stroke width, using--- a dash pattern. The offset is there to specify the starting--- point into the pattern, the value can be negative.------ > dashedStrokeWithOffset 3 [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $--- >     line (V2 0 100) (V2 200 100)------ <<docimages/dashed_stroke_with_offset.png>>----dashedStrokeWithOffset-    :: Geometry geom-    => Float       -- ^ Starting offset-    -> DashPattern -- ^ Dashing pattern to use for stroking-    -> Float       -- ^ Stroke width-    -> Join        -- ^ Which kind of join will be used-    -> (Cap, Cap)  -- ^ Start and end capping.-    -> geom        -- ^ List of elements to render-    -> Drawing px ()-dashedStrokeWithOffset _ [] width join caping prims =-    stroke width join caping prims-dashedStrokeWithOffset offset dashing width join caping prims =-    liftF $ DashedStroke offset dashing width join caping (toPrimitives prims) ()---- | Generate a strokable line out of points list.--- Just an helper around `lineFromPath`.------ > stroke 4 JoinRound (CapRound, CapRound) $--- >    polyline [V2 10 10, V2 100 70, V2 190 190]------ <<docimages/stroke_polyline.png>>----polyline :: [Point] -> [Primitive]-polyline = map LinePrim . lineFromPath---- | Generate a fillable polygon out of points list.--- Similar to the `polyline` function, but close the--- path.------ > fill $ polygon [V2 30 30, V2 100 70, V2 80 170]------ <<docimages/fill_polygon.png>>----polygon :: [Point] -> [Primitive]-polygon [] = []-polygon [_] = []-polygon [_,_] = []-polygon lst@(p:_) = polyline $ lst ++ [p]---- | Simply draw an image into the canvas. Take into account--- any previous transformation performed on the geometry.------ > drawImage textureImage 0 (V2 30 30)------ <<docimages/image_simple.png>>----drawImage :: Image px       -- ^ Image to be drawn-          -> StrokeWidth    -- ^ Border size, drawn with current texture.-          -> Point          -- ^ Position of the corner upper left of the image.-          -> Drawing px ()-drawImage img@Image { imageWidth = w, imageHeight = h } s p =-    drawImageAtSize img s p (fromIntegral w) (fromIntegral h)---- | Draw an image with the desired size------ > drawImageAtSize textureImage 2 (V2 30 30) 128 128------ <<docimages/image_resize.png>>----drawImageAtSize :: Image px    -- ^ Image to be drawn-                -> StrokeWidth -- ^ Border size, drawn with current texture.-                -> Point -- ^ Position of the corner upper left of the image.-                -> Float -- ^ Width of the drawn image-                -> Float -- ^ Height of the drawn image-                -> Drawing px ()-drawImageAtSize img@Image { imageWidth = w, imageHeight = h } borderSize ip-            reqWidth reqHeight-    | borderSize <= 0 =-        withTransformation (translate p <> scale scaleX scaleY) .-            withTexture (SampledTexture img) $ fill rect-    | otherwise = do-        withTransformation (translate p <> scale scaleX scaleY) $-            withTexture (SampledTexture img) $ fill rect-        stroke (borderSize / 2) (JoinMiter 0)-               (CapStraight 0, CapStraight 0) rect'-        where-          p = ip ^-^ V2 0.5 0.5-          rect = rectangle (V2 0 0) rw rh-          rect' = rectangle p reqWidth reqHeight--          (rw, rh) = (fromIntegral w, fromIntegral h)-          scaleX | reqWidth == 0 = 1-                 | otherwise = reqWidth / rw--          scaleY | reqHeight == 0 = 1-                 | otherwise = reqHeight / rh---- | Return a simple line ready to be stroked.------ > stroke 17 JoinRound (CapRound, CapRound) $--- >     line (V2 10 10) (V2 180 170)------ <<docimages/stroke_line.png>>----line :: Point -> Point -> [Primitive]-line p1 p2 = [LinePrim $ Line p1 p2]-+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE TypeSynonymInstances #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE ConstraintKinds #-}
+{-# LANGUAGE CPP #-}
+
+-- | Main module of Rasterific, an Haskell rasterization engine.
+--
+-- Creating an image is rather simple, here is a simple example
+-- of a drawing and saving it in a PNG file:
+--
+-- > import Codec.Picture( PixelRGBA8( .. ), writePng )
+-- > import Graphics.Rasterific
+-- > import Graphics.Rasterific.Texture
+-- >
+-- > main :: IO ()
+-- > main = do
+-- >   let white = PixelRGBA8 255 255 255 255
+-- >       drawColor = PixelRGBA8 0 0x86 0xc1 255
+-- >       recColor = PixelRGBA8 0xFF 0x53 0x73 255
+-- >       img = renderDrawing 400 200 white $
+-- >          withTexture (uniformTexture drawColor) $ do
+-- >             fill $ circle (V2 0 0) 30
+-- >             stroke 4 JoinRound (CapRound, CapRound) $
+-- >                    circle (V2 400 200) 40
+-- >             withTexture (uniformTexture recColor) .
+-- >                    fill $ rectangle (V2 100 100) 200 100
+-- >
+-- >   writePng "yourimage.png" img
+--
+-- <<docimages/module_example.png>>
+--
+-- The coordinate system is the picture classic one, with the origin in
+-- the upper left corner; with the y axis growing to the bottom and the
+-- x axis growing to the right:
+--
+-- <<docimages/coordinate.png>>
+--
+module Graphics.Rasterific
+    (
+      -- * Rasterization command
+      -- ** Filling
+      fill
+    , fillWithMethod
+    , renderMeshPatch
+      -- ** Stroking
+    , stroke
+    , dashedStroke
+    , dashedStrokeWithOffset
+      -- ** Text rendering
+    , printTextAt
+    , printTextRanges
+      -- ** Texturing
+    , withTexture
+    , withClipping
+    , withGroupOpacity
+      -- ** Transformations
+    , withTransformation
+    , withPathOrientation
+    , TextRange( .. )
+    , PointSize( .. )
+
+      -- * Generating images
+    , ModulablePixel
+    , RenderablePixel
+    , renderDrawing
+    , renderDrawingAtDpi
+    , renderDrawingAtDpiToPDF
+    , renderOrdersAtDpiToPdf 
+    , pathToPrimitives
+
+      -- * Rasterization types
+    , Texture
+    , Drawing
+    , Modulable
+
+      -- * Geometry description
+    , V2( .. )
+    , Point
+    , Vector
+    , CubicBezier( .. )
+    , Line( .. )
+    , Bezier( .. )
+    , Primitive( .. )
+    , Path( .. )
+    , PathCommand( .. )
+
+      -- * Generic geometry description
+    , Primitivable( .. )
+    , Geometry( .. )
+
+      -- * Generic geometry manipulation
+    , Transformable( .. )
+    , PointFoldable( .. )
+    , PlaneBoundable( .. )
+    , PlaneBound( .. )
+    , boundWidth
+    , boundHeight
+    , boundLowerLeftCorner
+
+      -- * Helpers
+      -- ** line
+    , line
+      -- ** Rectangle
+    , rectangle
+    , roundedRectangle
+      -- ** Circles
+    , circle
+    , ellipse
+      -- ** Polygons
+    , polyline
+    , polygon
+      -- ** Images
+    , drawImageAtSize
+    , drawImage
+    , cacheDrawing
+
+      -- ** Geometry Helpers
+    , clip
+    , bezierFromPath
+    , lineFromPath
+    , cubicBezierFromPath
+    , firstTangeantOf
+    , lastTangeantOf
+    , firstPointOf
+    , lastPointOf
+
+      -- *** Arc traduction
+    , Direction( .. )
+    , arcInDirection
+
+      -- * Rasterization control
+    , Join( .. )
+    , Cap( .. )
+    , SamplerRepeat( .. )
+    , FillMethod( .. )
+    , PatchInterpolation( .. )
+    , DashPattern
+    , drawOrdersOfDrawing
+
+      -- * Debugging helper
+    , dumpDrawing
+    ) where
+
+#if !MIN_VERSION_base(4,8,0)
+import Control.Applicative( (<$>) )
+import Data.Foldable( foldMap )
+import Data.Monoid( Monoid( .. ) )
+#endif
+
+import Data.Monoid( (<>) )
+
+import Control.Monad.Free( Free( .. ), liftF )
+import Control.Monad.Free.Church( fromF )
+import Control.Monad.ST( ST, runST )
+import Control.Monad.State( modify, execState )
+import Data.Maybe( fromMaybe )
+import Codec.Picture.Types( Image( .. )
+                          , Pixel( .. )
+                          , PixelRGBA8
+                          , pixelMapXY )
+
+import qualified Data.ByteString.Lazy as LB
+import qualified Data.Vector as V
+
+import Graphics.Rasterific.Compositor
+import Graphics.Rasterific.Linear( V2( .. ), (^+^), (^-^) )
+import Graphics.Rasterific.Rasterize
+import Graphics.Rasterific.MicroPdf
+{-import Graphics.Rasterific.Texture-}
+import Graphics.Rasterific.ComplexPrimitive
+import Graphics.Rasterific.Types
+import Graphics.Rasterific.Line
+import Graphics.Rasterific.QuadraticBezier
+import Graphics.Rasterific.CubicBezier
+import Graphics.Rasterific.StrokeInternal
+import Graphics.Rasterific.Transformations
+import Graphics.Rasterific.PlaneBoundable
+import Graphics.Rasterific.Immediate
+import Graphics.Rasterific.PathWalker
+import Graphics.Rasterific.Arc
+import Graphics.Rasterific.Command
+import Graphics.Rasterific.PatchTypes
+import Graphics.Rasterific.Patch
+import Graphics.Rasterific.MeshPatch
+{-import Graphics.Rasterific.TensorPatch-}
+
+import Graphics.Text.TrueType( Font
+                             , Dpi
+                             , PointSize( .. )
+                             )
+
+{-import Debug.Trace-}
+{-import Text.Printf-}
+
+------------------------------------------------
+----    Free Monad DSL section
+------------------------------------------------
+
+-- | Define the texture applyied to all the children
+-- draw call.
+--
+-- > withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 255) $ do
+-- >     fill $ circle (V2 50 50) 20
+-- >     fill $ circle (V2 100 100) 20
+-- >     withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255)
+-- >          $ circle (V2 150 150) 20
+--
+-- <<docimages/with_texture.png>>
+--
+withTexture :: Texture px -> Drawing px () -> Drawing px ()
+withTexture texture subActions =
+    liftF $ SetTexture texture subActions ()
+
+-- | Will render the whole subaction with a given group opacity, after
+-- each element has been rendered. That means that completly opaque
+-- overlapping shapes will be rendered transparently, not one after
+-- another.
+--
+-- > withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255) $
+-- >     stroke 3 JoinRound (CapRound, CapRound) $
+-- >         line (V2 0 100) (V2 200 100)
+-- >
+-- > withGroupOpacity 128 $ do
+-- >    withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 255) .
+-- >       fill $ circle (V2 70 100) 60
+-- >    withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 255) .
+-- >       fill $ circle (V2 120 100) 60
+--
+-- <<docimages/group_opacity.png>>
+--
+-- To be compared to the item opacity
+--
+-- > withTexture (uniformTexture $ PixelRGBA8 0xFF 0x53 0x73 255) $
+-- >     stroke 3 JoinRound (CapRound, CapRound) $
+-- >         line (V2 0 100) (V2 200 100)
+-- > withTexture (uniformTexture $ PixelRGBA8 0 0x86 0xc1 128) .
+-- >    fill $ circle (V2 70 100) 60
+-- > withTexture (uniformTexture $ PixelRGBA8 0xff 0xf4 0xc1 128) .
+-- >    fill $ circle (V2 120 100) 60
+--
+-- <<docimages/item_opacity.png>>
+withGroupOpacity :: PixelBaseComponent px -> Drawing px ()-> Drawing px ()
+withGroupOpacity opa sub = liftF $ WithGlobalOpacity opa sub ()
+
+-- | Draw all the sub drawing commands using a transformation.
+withTransformation :: Transformation -> Drawing px () -> Drawing px ()
+withTransformation trans sub =
+    liftF $ WithTransform trans sub ()
+
+-- | This command allows you to draw primitives on a given curve,
+-- for example, you can draw text on a curve:
+--
+-- > let path = Path (V2 100 180) False
+-- >                 [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)] in
+-- > stroke 3 JoinRound (CapStraight 0, CapStraight 0) path
+-- > withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+-- >   withPathOrientation path 0 $
+-- >     printTextAt font (PointSize 24) (V2 0 0) "Text on path"
+--
+-- <<docimages/text_on_path.png>>
+--
+-- You can note that the position of the baseline match the size of the
+-- characters.
+--
+-- You are not limited to text drawing while using this function,
+-- you can draw arbitrary geometry like in the following example:
+--
+-- > let path = Path (V2 100 180) False
+-- >                 [PathCubicBezierCurveTo (V2 20 20) (V2 170 20) (V2 300 200)]
+-- > withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+-- >   stroke 3 JoinRound (CapStraight 0, CapStraight 0) path
+-- > 
+-- > withPathOrientation path 0 $ do
+-- >   printTextAt font (PointSize 24) (V2 0 0) "TX"
+-- >   fill $ rectangle (V2 (-10) (-10)) 30 20
+-- >   fill $ rectangle (V2 45 0) 10 20
+-- >   fill $ rectangle (V2 60 (-10)) 20 20
+-- >   fill $ rectangle (V2 100 (-15)) 20 50
+--
+-- <<docimages/geometry_on_path.png>>
+--
+withPathOrientation :: Path            -- ^ Path directing the orientation.
+                    -> Float           -- ^ Basline Y axis position, used to align text properly.
+                    -> Drawing px ()   -- ^ The sub drawings.
+                    -> Drawing px ()
+withPathOrientation path p sub =
+    liftF $ WithPathOrientation path p sub ()
+
+-- | Fill some geometry. The geometry should be "looping",
+-- ie. the last point of the last primitive should
+-- be equal to the first point of the first primitive.
+--
+-- The primitive should be connected.
+--
+-- > fill $ circle (V2 100 100) 75
+--
+-- <<docimages/fill_circle.png>>
+--
+fill :: Geometry geom => geom -> Drawing px ()
+fill prims = liftF $ Fill FillWinding (toPrimitives prims) ()
+
+-- | This function let you choose how to fill the primitives
+-- in case of self intersection. See `FillMethod` documentation
+-- for more information.
+fillWithMethod :: Geometry geom
+               => FillMethod -> geom -> Drawing px ()
+fillWithMethod method prims =
+    liftF $ Fill method (toPrimitives prims) ()
+
+-- | Draw some geometry using a clipping path.
+--
+-- > withClipping (fill $ circle (V2 100 100) 75) $
+-- >     mapM_ (stroke 7 JoinRound (CapRound, CapRound))
+-- >       [line (V2 0 yf) (V2 200 (yf + 10))
+-- >                      | y <- [5 :: Int, 17 .. 200]
+-- >                      , let yf = fromIntegral y ]
+--
+-- <<docimages/with_clipping.png>>
+--
+withClipping
+    :: (forall innerPixel. Drawing innerPixel ()) -- ^ The clipping path
+    -> Drawing px () -- ^ The actual geometry to clip
+    -> Drawing px ()
+withClipping clipPath drawing =
+    liftF $ WithCliping clipPath drawing ()
+
+-- | Will stroke geometry with a given stroke width.
+-- The elements should be connected
+--
+-- > stroke 5 JoinRound (CapRound, CapRound) $ circle (V2 100 100) 75
+--
+-- <<docimages/stroke_circle.png>>
+--
+stroke :: (Geometry geom)
+       => Float       -- ^ Stroke width
+       -> Join        -- ^ Which kind of join will be used
+       -> (Cap, Cap)  -- ^ Start and end capping.
+       -> geom        -- ^ List of elements to render
+       -> Drawing px ()
+stroke width join caping prims =
+    liftF $ Stroke width join caping (toPrimitives prims) ()
+
+-- | Draw a string at a given position.
+-- Text printing imply loading a font, there is no default
+-- font (yet). Below an example of font rendering using a
+-- font installed on Microsoft Windows.
+--
+-- > import Graphics.Text.TrueType( loadFontFile )
+-- > import Codec.Picture( PixelRGBA8( .. ), writePng )
+-- > import Graphics.Rasterific
+-- > import Graphics.Rasterific.Texture
+-- >
+-- > main :: IO ()
+-- > main = do
+-- >   fontErr <- loadFontFile "test_fonts/DejaVuSans.ttf"
+-- >   case fontErr of
+-- >     Left err -> putStrLn err
+-- >     Right font ->
+-- >       writePng "text_example.png" .
+-- >           renderDrawing 300 70 (PixelRGBA8 255 255 255 255)
+-- >               . withTexture (uniformTexture $ PixelRGBA8 0 0 0 255) $
+-- >                       printTextAt font (PointSize 12) (V2 20 40)
+-- >                            "A simple text test!"
+--
+-- <<docimages/text_example.png>>
+--
+-- You can use any texture, like a gradient while rendering text.
+--
+printTextAt :: Font            -- ^ Drawing font
+            -> PointSize       -- ^ font Point size
+            -> Point           -- ^ Drawing starting point (base line)
+            -> String          -- ^ String to print
+            -> Drawing px ()
+printTextAt font pointSize point string =
+    liftF $ TextFill point [description] ()
+  where
+    description = TextRange
+        { _textFont    = font
+        , _textSize    = pointSize
+        , _text        = string
+        , _textTexture = Nothing
+        }
+
+-- | Render a mesh patch as an object. Warning, there is
+-- no antialiasing on mesh patch objects!
+renderMeshPatch :: PatchInterpolation -> MeshPatch px -> Drawing px ()
+renderMeshPatch i mesh = liftF $ MeshPatchRender i mesh ()
+
+-- | Print complex text, using different texture font and
+-- point size for different parts of the text.
+--
+-- > let blackTexture =
+-- >       Just . uniformTexture $ PixelRGBA8 0 0 0 255
+-- >     redTexture =
+-- >       Just . uniformTexture $ PixelRGBA8 255 0 0 255
+-- > in
+-- > printTextRanges (V2 20 40)
+-- >   [ TextRange font1 (PointSize 12) "A complex " blackTexture
+-- >   , TextRange font2 (PointSize 8) "text test" redTexture]
+--
+-- <<docimages/text_complex_example.png>>
+--
+printTextRanges :: Point            -- ^ Starting point of the base line
+                -> [TextRange px]   -- ^ Ranges description to be printed
+                -> Drawing px ()
+printTextRanges point ranges = liftF $ TextFill point ranges ()
+
+data RenderContext px = RenderContext
+    { currentClip           :: Maybe (Texture (PixelBaseComponent px))
+    , currentTexture        :: Texture px
+    , currentTransformation :: Maybe (Transformation, Transformation)
+    }
+
+-- | Function to call in order to start the image creation.
+-- Tested pixels type are PixelRGBA8 and Pixel8, pixel types
+-- in other colorspace will probably produce weird results.
+-- Default DPI is 96
+renderDrawing
+    :: forall px . (RenderablePixel px)
+    => Int -- ^ Rendering width
+    -> Int -- ^ Rendering height
+    -> px  -- ^ Background color
+    -> Drawing px () -- ^ Rendering action
+    -> Image px
+renderDrawing width height = renderDrawingAtDpi width height 96
+
+renderOrdersAtDpiToPdf 
+    :: Int -- ^ Rendering width
+    -> Int -- ^ Rendering height
+    -> Dpi -- ^ Current DPI used for text rendering.
+    -> [DrawOrder PixelRGBA8]  -- ^ Drawing Orders
+    -> LB.ByteString
+renderOrdersAtDpiToPdf w h dpi =
+  renderOrdersToPdf renderer w h dpi
+    where
+      renderer :: forall px . RenderablePixel px => Drawing px () -> [DrawOrder px]
+      renderer = drawOrdersOfDrawing w h dpi emptyPx
+
+renderDrawingAtDpiToPDF
+    :: Int -- ^ Rendering width
+    -> Int -- ^ Rendering height
+    -> Dpi -- ^ Current DPI used for text rendering.
+    -> Drawing PixelRGBA8 () -- ^ Rendering action
+    -> LB.ByteString
+renderDrawingAtDpiToPDF w h dpi =
+  renderDrawingToPdf renderer w h dpi
+    where
+      renderer :: forall px . RenderablePixel px => Drawing px () -> [DrawOrder px]
+      renderer = drawOrdersOfDrawing w h dpi emptyPx
+
+-- | Function to call in order to start the image creation.
+-- Tested pixels type are PixelRGBA8 and Pixel8, pixel types
+-- in other colorspace will probably produce weird results.
+renderDrawingAtDpi
+    :: forall px . (RenderablePixel px)
+    => Int -- ^ Rendering width
+    -> Int -- ^ Rendering height
+    -> Dpi -- ^ Current DPI used for text rendering.
+    -> px  -- ^ Background color
+    -> Drawing px () -- ^ Rendering action
+    -> Image px
+renderDrawingAtDpi width height dpi background drawing =
+    runST $ runDrawContext width height background
+          $ mapM_ fillOrder
+          $ drawOrdersOfDrawing width height dpi background drawing
+
+cacheOrders :: forall px. (RenderablePixel px)
+            => Maybe (Image px -> ImageTransformer px) -> [DrawOrder px] -> Drawing px ()
+cacheOrders imageFilter orders = case imageFilter of
+    Nothing -> drawImage resultImage 0 cornerUpperLeft
+    Just f -> drawImage (pixelMapXY (f resultImage) resultImage) 0 cornerUpperLeft
+  where
+   PlaneBound mini maxi = foldMap planeBounds orders
+   cornerUpperLeftInt = floor <$> mini :: V2 Int
+   cornerUpperLeft = fromIntegral <$> cornerUpperLeftInt
+
+   V2 width height = maxi ^-^ cornerUpperLeft ^+^ V2 1 1
+   
+   shiftOrder order@DrawOrder { _orderPrimitives = prims } =
+       order { _orderPrimitives = fmap (transform (^-^ cornerUpperLeft)) <$> prims 
+             , _orderTexture =
+                 WithTextureTransform (translate cornerUpperLeft) $ _orderTexture order
+             }
+   
+   resultImage =
+     runST $ runDrawContext (ceiling width) (ceiling height) emptyPx
+           $ mapM_ (fillOrder . shiftOrder) orders
+
+-- | This function perform an optimisation, it will render a drawing
+-- to an image interanlly and create a new order to render this image
+-- instead of the geometry, effectively cuting the geometry generation
+-- part.
+--
+-- It can save execution time when drawing complex elements multiple
+-- times.
+cacheDrawing
+    :: forall px . (RenderablePixel px)
+    => Int -- ^ Max rendering width
+    -> Int -- ^ Max rendering height
+    -> Dpi
+    -> Drawing px ()
+    -> Drawing px ()
+cacheDrawing maxWidth maxHeight dpi sub =
+  cacheOrders Nothing $ drawOrdersOfDrawing maxWidth maxHeight dpi emptyPx sub
+
+preComputeTexture :: (RenderablePixel px)
+                  => Int -> Int -> Texture px -> Texture px
+preComputeTexture w h = go where
+  go :: RenderablePixel px => Texture px -> Texture px
+  go t = case t of
+    SolidTexture _ -> t
+    LinearGradientTexture _ _ -> t
+    RadialGradientTexture _ _ _ -> t
+    RadialGradientWithFocusTexture _ _ _ _ -> t
+    WithSampler s sub -> WithSampler s $ go sub
+    WithTextureTransform trans sub -> WithTextureTransform trans $ go sub
+    SampledTexture _ -> t
+    RawTexture _ -> t
+    ShaderTexture _ -> t
+    ModulateTexture t1 t2 -> ModulateTexture (go t1) (go t2)
+    PatternTexture _ _ _ _ _ -> t
+    AlphaModulateTexture i m -> AlphaModulateTexture (go i) (go m)
+    MeshPatchTexture i m ->
+        RawTexture $ renderDrawing w h emptyPx $ renderMeshPatch i m
+
+-- | Transform a drawing into a serie of low-level drawing orders.
+drawOrdersOfDrawing
+    :: forall px . (RenderablePixel px) 
+    => Int -- ^ Rendering width
+    -> Int -- ^ Rendering height
+    -> Dpi -- ^ Current assumed DPI
+    -> px  -- ^ Background color
+    -> Drawing px () -- ^ Rendering action
+    -> [DrawOrder px]
+drawOrdersOfDrawing width height dpi background drawing =
+    go initialContext (fromF drawing) []
+  where
+    initialContext = RenderContext Nothing stupidDefaultTexture Nothing
+    clipBackground = emptyValue :: PixelBaseComponent px
+    clipForeground = fullValue :: PixelBaseComponent px
+
+    clipRender ctxt =
+      renderDrawing width height clipBackground . 
+        transformer .
+          withTexture (SolidTexture clipForeground)
+       where 
+         transformer = maybe id (withTransformation . fst) $ currentTransformation ctxt
+
+
+    subRender :: (forall s. DrawContext (ST s) px ()) -> Image px
+    subRender act =
+      runST $ runDrawContext width height background act
+
+    textureOf ctxt@RenderContext { currentTransformation = Just (_, t) } =
+        WithTextureTransform t $ currentTexture ctxt
+    textureOf ctxt = currentTexture ctxt
+
+    geometryOf :: Transformable a => RenderContext px -> a -> a
+    geometryOf RenderContext { currentTransformation = Just (trans, _) } =
+        transform (applyTransformation trans)
+    geometryOf _ = id
+
+    geometryOfO RenderContext { currentTransformation = Just (trans, _) } =
+        transformOrder (applyTransformation trans)
+    geometryOfO _ = id
+
+    stupidDefaultTexture =
+        SolidTexture $ colorMap (const clipBackground) background
+
+    go :: RenderContext px -> Free (DrawCommand px) () -> [DrawOrder px]
+       -> [DrawOrder px]
+    go _ (Pure ()) rest = rest
+    go ctxt (Free (WithGlobalOpacity opa sub next)) rest =
+        go ctxt (Free (WithImageEffect opacifier sub next)) rest
+      where 
+        -- Todo: a colorMapWithAlpha is really needed in JP API.
+        opacifier _ _ _ px = mixWithAlpha ignore alphaModulate px px
+        ignore _ _ a = a
+        alphaModulate _ v = opa `modulate` v
+
+    go ctxt (Free (WithImageEffect effect sub next)) rest =
+        go freeContext (fromF cached) after
+      where
+        cached = cacheOrders (Just effect) $ go ctxt (fromF sub) []
+        after = go ctxt next rest
+        freeContext = ctxt { currentClip = Nothing, currentTransformation = Nothing }
+
+
+    go ctxt (Free (WithPathOrientation path base sub next)) rest = final where
+      final = orders <> go ctxt next rest
+      images = go ctxt (fromF sub) []
+
+      drawer trans _ order =
+        modify (transformOrder (applyTransformation trans) order :)
+
+      orders = reverse $ execState (drawOrdersOnPath drawer 0 base path images) []
+
+    go ctxt (Free (WithTransform trans sub next)) rest = final where
+      trans'
+        | Just (t, _) <- currentTransformation ctxt = t <> trans
+        | otherwise = trans
+      invTrans = fromMaybe mempty $ inverseTransformation trans'
+      after = go ctxt next rest
+      subContext =
+          ctxt { currentTransformation = Just (trans', invTrans) }
+
+      final = go subContext (fromF sub) after
+
+    go ctxt (Free (CustomRender cust next)) rest = order : after where
+      after = go ctxt next rest
+      order = DrawOrder 
+            { _orderPrimitives = []
+            , _orderTexture    = textureOf ctxt
+            , _orderFillMethod = FillWinding
+            , _orderMask       = currentClip ctxt
+            , _orderDirect     = cust
+            }
+
+    go ctxt (Free (MeshPatchRender i mesh next)) rest = order : after where
+      after = go ctxt next rest
+      rendering :: DrawContext (ST s) px ()
+      rendering = case i of
+        PatchBilinear -> mapM_ rasterizeCoonPatch $ coonPatchesOf $ geometryOf ctxt opaqueMesh 
+        PatchBicubic ->
+            mapM_ rasterizeCoonPatch
+                . cubicCoonPatchesOf 
+                $ calculateMeshColorDerivative $ geometryOf ctxt opaqueMesh 
+
+      hasTransparency =
+          V.any ((/= fullValue) . pixelOpacity) $ _meshColors mesh
+
+      opacifier px = mixWithAlpha (\_ _ a -> a) (\_ _ -> fullValue) px px
+
+      opaqueMesh = opacifier <$> mesh
+      transparencyMesh = pixelOpacity <$> mesh
+
+      clipPath
+        | not hasTransparency = currentClip ctxt
+        | otherwise =
+            let newMask :: Image (PixelBaseComponent (PixelBaseComponent px))
+                newMask = clipRender ctxt $ renderMeshPatch i transparencyMesh in
+            case currentClip ctxt of
+              Nothing -> Just $ RawTexture newMask
+              Just v -> Just $ ModulateTexture v (RawTexture newMask)
+
+      order = case clipPath of
+        -- Good, we can directly render on the final canvas
+        Nothing -> DrawOrder 
+            { _orderPrimitives = []
+            , _orderTexture    = textureOf ctxt
+            , _orderFillMethod = FillWinding
+            , _orderMask       = clipPath
+            , _orderDirect     = rendering
+            }
+        Just c -> DrawOrder
+            { _orderPrimitives = [geometryOf ctxt $ rectangle (V2 0 0) (fromIntegral width) (fromIntegral height)]
+            , _orderTexture    = AlphaModulateTexture (RawTexture $ subRender rendering) c
+            , _orderFillMethod = FillWinding
+            , _orderMask       = Nothing
+            , _orderDirect     = return ()
+            }
+
+    go ctxt (Free (Fill method prims next)) rest = order : after where
+      after = go ctxt next rest
+      order = DrawOrder 
+            { _orderPrimitives = [geometryOf ctxt prims]
+            , _orderTexture    = textureOf ctxt
+            , _orderFillMethod = method
+            , _orderMask       = currentClip ctxt
+            , _orderDirect     = return ()
+            }
+
+    go ctxt (Free (Stroke w j cap prims next)) rest =
+        go ctxt (Free $ Fill FillWinding prim' next) rest
+            where prim' = listOfContainer $ strokize w j cap prims
+
+    go ctxt (Free (SetTexture tx sub next)) rest =
+        go (ctxt { currentTexture = preComputeTexture width height tx }) (fromF sub) $
+            go ctxt next rest
+
+    go ctxt (Free (DashedStroke o d w j cap prims next)) rest =
+        foldr recurse after $ dashedStrokize o d w j cap prims
+      where
+        after = go ctxt next rest
+        recurse sub =
+            go ctxt (liftF $ Fill FillWinding sub ())
+
+    go ctxt (Free (TextFill p descriptions next)) rest = calls <> go ctxt next rest where
+      calls =
+        geometryOfO ctxt <$> textToDrawOrders dpi (currentTexture ctxt) p descriptions
+
+    go ctxt (Free (WithCliping clipPath path next)) rest =
+        go (ctxt { currentClip = newModuler }) (fromF path) $
+            go ctxt next rest
+      where
+        modulationTexture :: Texture (PixelBaseComponent px)
+        modulationTexture = RawTexture $ clipRender ctxt clipPath
+
+        newModuler = Just . subModuler $ currentClip ctxt
+
+        subModuler Nothing = modulationTexture
+        subModuler (Just v) =
+            ModulateTexture v modulationTexture
+
+-- | With stroke geometry with a given stroke width, using
+-- a dash pattern.
+--
+-- > dashedStroke [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $
+-- >     line (V2 0 100) (V2 200 100)
+--
+-- <<docimages/dashed_stroke.png>>
+--
+dashedStroke
+    :: Geometry geom
+    => DashPattern -- ^ Dashing pattern to use for stroking
+    -> Float       -- ^ Stroke width
+    -> Join        -- ^ Which kind of join will be used
+    -> (Cap, Cap)  -- ^ Start and end capping.
+    -> geom        -- ^ List of elements to render
+    -> Drawing px ()
+dashedStroke = dashedStrokeWithOffset 0.0
+
+-- | With stroke geometry with a given stroke width, using
+-- a dash pattern. The offset is there to specify the starting
+-- point into the pattern, the value can be negative.
+--
+-- > dashedStrokeWithOffset 3 [5, 10, 5] 3 JoinRound (CapRound, CapStraight 0) $
+-- >     line (V2 0 100) (V2 200 100)
+--
+-- <<docimages/dashed_stroke_with_offset.png>>
+--
+dashedStrokeWithOffset
+    :: Geometry geom
+    => Float       -- ^ Starting offset
+    -> DashPattern -- ^ Dashing pattern to use for stroking
+    -> Float       -- ^ Stroke width
+    -> Join        -- ^ Which kind of join will be used
+    -> (Cap, Cap)  -- ^ Start and end capping.
+    -> geom        -- ^ List of elements to render
+    -> Drawing px ()
+dashedStrokeWithOffset _ [] width join caping prims =
+    stroke width join caping prims
+dashedStrokeWithOffset offset dashing width join caping prims =
+    liftF $ DashedStroke offset dashing width join caping (toPrimitives prims) ()
+
+-- | Generate a strokable line out of points list.
+-- Just an helper around `lineFromPath`.
+--
+-- > stroke 4 JoinRound (CapRound, CapRound) $
+-- >    polyline [V2 10 10, V2 100 70, V2 190 190]
+--
+-- <<docimages/stroke_polyline.png>>
+--
+polyline :: [Point] -> [Primitive]
+polyline = map LinePrim . lineFromPath
+
+-- | Generate a fillable polygon out of points list.
+-- Similar to the `polyline` function, but close the
+-- path.
+--
+-- > fill $ polygon [V2 30 30, V2 100 70, V2 80 170]
+--
+-- <<docimages/fill_polygon.png>>
+--
+polygon :: [Point] -> [Primitive]
+polygon [] = []
+polygon [_] = []
+polygon [_,_] = []
+polygon lst@(p:_) = polyline $ lst ++ [p]
+
+-- | Simply draw an image into the canvas. Take into account
+-- any previous transformation performed on the geometry.
+--
+-- > drawImage textureImage 0 (V2 30 30)
+--
+-- <<docimages/image_simple.png>>
+--
+drawImage :: Image px       -- ^ Image to be drawn
+          -> StrokeWidth    -- ^ Border size, drawn with current texture.
+          -> Point          -- ^ Position of the corner upper left of the image.
+          -> Drawing px ()
+drawImage img@Image { imageWidth = w, imageHeight = h } s p =
+    drawImageAtSize img s p (fromIntegral w) (fromIntegral h)
+
+-- | Draw an image with the desired size
+--
+-- > drawImageAtSize textureImage 2 (V2 30 30) 128 128
+--
+-- <<docimages/image_resize.png>>
+--
+drawImageAtSize :: Image px    -- ^ Image to be drawn
+                -> StrokeWidth -- ^ Border size, drawn with current texture.
+                -> Point -- ^ Position of the corner upper left of the image.
+                -> Float -- ^ Width of the drawn image
+                -> Float -- ^ Height of the drawn image
+                -> Drawing px ()
+drawImageAtSize img@Image { imageWidth = w, imageHeight = h } borderSize ip
+            reqWidth reqHeight
+    | borderSize <= 0 =
+        withTransformation (translate p <> scale scaleX scaleY) .
+            withTexture (SampledTexture img) $ fill rect
+    | otherwise = do
+        withTransformation (translate p <> scale scaleX scaleY) $
+            withTexture (SampledTexture img) $ fill rect
+        stroke (borderSize / 2) (JoinMiter 0)
+               (CapStraight 0, CapStraight 0) rect'
+        where
+          p = ip ^-^ V2 0.5 0.5
+          rect = rectangle (V2 0 0) rw rh
+          rect' = rectangle p reqWidth reqHeight
+
+          (rw, rh) = (fromIntegral w, fromIntegral h)
+          scaleX | reqWidth == 0 = 1
+                 | otherwise = reqWidth / rw
+
+          scaleY | reqHeight == 0 = 1
+                 | otherwise = reqHeight / rh
+
+-- | Return a simple line ready to be stroked.
+--
+-- > stroke 17 JoinRound (CapRound, CapRound) $
+-- >     line (V2 10 10) (V2 180 170)
+--
+-- <<docimages/stroke_line.png>>
+--
+line :: Point -> Point -> [Primitive]
+line p1 p2 = [LinePrim $ Line p1 p2]
+
+ src/Graphics/Rasterific/Arc.hs view
@@ -0,0 +1,170 @@+-- | Translation of cairo-arc.c
+module Graphics.Rasterific.Arc( Direction( .. ), arcInDirection ) where
+
+import Data.Maybe( fromMaybe )
+import Data.Monoid( (<>) )
+import qualified Data.Vector.Unboxed as VU
+
+import Graphics.Rasterific.Transformations
+import Graphics.Rasterific.Linear
+import Graphics.Rasterific.Types
+
+
+errorTable :: VU.Vector (Float, Float)
+errorTable = VU.imap calcAngle errors where
+  calcAngle i a = (pi / fromIntegral i, a)
+  errors = VU.fromListN 10
+    [ 0.0185185185185185036127
+    , 0.000272567143730179811158
+    , 2.38647043651461047433e-05
+    , 4.2455377443222443279e-06
+    , 1.11281001494389081528e-06
+    , 3.72662000942734705475e-07
+    , 1.47783685574284411325e-07
+    , 6.63240432022601149057e-08
+    , 3.2715520137536980553e-08
+    , 1.73863223499021216974e-08
+    , 9.81410988043554039085e-09 ]
+
+{- Spline deviation from the circle in radius would be given by:
+
+    error = sqrt (x**2 + y**2) - 1
+
+   A simpler error function to work with is:
+
+    e = x**2 + y**2 - 1
+
+   From "Good approximation of circles by curvature-continuous Bezier
+   curves", Tor Dokken and Morten Daehlen, Computer Aided Geometric
+   Design 8 (1990) 22-41, we learn:
+
+    abs (max(e)) = 4/27 * sin**6(angle/4) / cos**2(angle/4)
+
+   and
+    abs (error) =~ 1/2 * e
+
+   Of course, this error value applies only for the particular spline
+   approximation that is used in _cairo_gstate_arc_segment.  -}
+fixAngleError :: Int -> Float -> Float
+fixAngleError i tolerance
+    | errorNormalized > tolerance = fixAngleError (i + 1) tolerance
+    | otherwise = angle
+  where
+    angle = pi / fromIntegral i
+    errorNormalized = 2.0/27.0 * (sin (angle / 4) ** 6) / (cos (angle / 4) ** 2)
+
+arcMaxAngleForToleranceNormalized :: Float -> Float
+arcMaxAngleForToleranceNormalized tolerance = fixAngleError (angleIndex + 1) tolerance
+  where
+    angleIndex = fromMaybe
+      (VU.length errorTable) $
+       VU.findIndex ((< tolerance) . snd) errorTable
+
+arcSegmentsNeeded :: Float -> Float -> Transformation -> Float
+                  -> Int
+arcSegmentsNeeded angle radius trans tolerance = ceiling (angle / maxAngle) where
+  -- the error is amplified by at most the length of the
+  -- major axis of the circle; see cairo-pen.c for a more detailed analysis
+  -- of this.
+  majorAxis = matrixTransformedCircleMajorAxis trans radius
+  maxAngle = arcMaxAngleForToleranceNormalized (tolerance / majorAxis)
+
+-- determine the length of the major axis of a circle of the given radius
+-- after applying the transformation matrix.
+matrixTransformedCircleMajorAxis :: Transformation -> Float -> Float
+matrixTransformedCircleMajorAxis (Transformation a c _
+                                                 b d _) radius =
+     radius * sqrt (f + norm v)
+  where
+    i = a*a + b*b;
+    j = c*c + d*d;
+
+    f = 0.5 * (i + j)
+    v = V2 (0.5 * (i - j)) (a * c + b * d)
+    -- we don't need the minor axis length, which is
+    -- double min = radius * sqrt (f - sqrt (g*g+h*h));
+
+-- | Direction of the arc
+data Direction = Forward | Backward
+
+clampAngle :: Float -> Float -> Float
+clampAngle angleMin = go where
+  go angleMax
+    | angleMax - angleMin > 4 * pi = go $ angleMax - 2 * pi
+    | otherwise = angleMax
+
+subdivideAngles :: (Monoid m)
+                => Direction -> (Float -> Float -> m) -> Float -> Float -> m
+subdivideAngles dir f aMin = go aMin . clampAngle aMin where
+  go angleMin angleMax | deltaAngle > pi = case dir of
+      Forward -> go angleMin angleMid <> go angleMid angleMax
+      Backward -> go angleMid angleMax <> go angleMin angleMid
+    where
+      deltaAngle = angleMax - angleMin
+      angleMid = angleMin + deltaAngle / 2
+  go angleMin angleMax = f angleMin angleMax
+
+
+{-  We want to draw a single spline approximating a circular arc radius
+   R from angle A to angle B. Since we want a symmetric spline that
+   matches the endpoints of the arc in position and slope, we know
+   that the spline control points must be:
+
+	(R * cos(A), R * sin(A))
+	(R * cos(A) - h * sin(A), R * sin(A) + h * cos (A))
+	(R * cos(B) + h * sin(B), R * sin(B) - h * cos (B))
+	(R * cos(B), R * sin(B))
+
+   for some value of h.
+
+   "Approximation of circular arcs by cubic poynomials", Michael
+   Goldapp, Computer Aided Geometric Design 8 (1991) 227-238, provides
+   various values of h along with error analysis for each.
+
+   From that paper, a very practical value of h is:
+
+	h = 4/3 * tan(angle/4)
+
+   This value does not give the spline with minimal error, but it does
+   provide a very good approximation, (6th-order convergence), and the
+   error expression is quite simple, (see the comment for
+   _arc_error_normalized).
+-}
+arcSegment :: Point -> Float -> Float -> Float -> PathCommand
+arcSegment (V2 xc yc) radius angleA angleB = PathCubicBezierCurveTo p1 p2 p3 where
+  rSinA = radius * sin angleA
+  rCosA = radius * cos angleA
+  rSinB = radius * sin angleB
+  rCosB = radius * cos angleB
+
+  h = 4.0/3.0 * tan ((angleB - angleA) / 4.0)
+
+  p1 = V2 (xc + rCosA - h * rSinA) (yc + rSinA + h * rCosA)
+  p2 = V2 (xc + rCosB + h * rSinB) (yc + rSinB - h * rCosB)
+  p3 = V2 (xc + rCosB) (yc + rSinB)
+
+-- | Translate an arc with a definition similar to the
+-- one given in Cairo to a list of bezier path command
+arcInDirection :: Point -- ^ center
+               -> Float -- ^ Radius
+               -> Direction
+               -> Float -- ^ Tolerance
+               -> Float -- ^ Angle minimum
+               -> Float -- ^ Angle maximum
+               -> [PathCommand]
+arcInDirection p@(V2 px py) radius dir tolerance 
+  | isNaN px || isNaN py || isNaN radius = mempty
+  | otherwise = subdivideAngles dir go where
+  go angleMin angleMax = commands where
+    deltaAngle = angleMax - angleMin
+    segmentCount = arcSegmentsNeeded deltaAngle radius mempty tolerance
+
+    (angle, angleStep) = case dir of
+      Forward -> (angleMin, deltaAngle / fromIntegral segmentCount)
+      Backward -> (angleMax, - deltaAngle / fromIntegral segmentCount)
+
+    commands =
+        [arcSegment p radius a (a + angleStep)
+            | i <- [0 .. segmentCount - 1]
+            , let a = angle + angleStep * fromIntegral i]
+
src/Graphics/Rasterific/CubicBezier/FastForwardDifference.hs view
@@ -1,199 +1,199 @@-{-# LANGUAGE BangPatterns #-}-{-# LANGUAGE FlexibleContexts #-}-{-# LANGUAGE RecordWildCards #-}-module Graphics.Rasterific.CubicBezier.FastForwardDifference-    ( ForwardDifferenceCoefficient( .. )-    , bezierToForwardDifferenceCoeff-    , rasterizerCubicBezier-    , rasterizeTensorPatch-    , rasterizeCoonPatch-    , estimateFDStepCount-    ) where--import Control.Monad.Primitive( PrimMonad )-import Control.Monad.State( lift, get )-import Control.Monad.ST( ST )-import Data.Bits( unsafeShiftL )--import Codec.Picture( PixelRGBA8 )-import Codec.Picture.Types( MutableImage( .. ) )--import Graphics.Rasterific.Compositor-import Graphics.Rasterific.Immediate-import Graphics.Rasterific.Types-import Graphics.Rasterific.Linear-import Graphics.Rasterific.BiSampleable-import Graphics.Rasterific.PatchTypes-import Graphics.Rasterific.Shading--data ForwardDifferenceCoefficient = ForwardDifferenceCoefficient-    { _fdA :: {-# UNPACK #-} !Float-    , _fdB :: {-# UNPACK #-} !Float-    , _fdC :: {-# UNPACK #-} !Float-    }---- | Given a cubic curve, return the initial step size and--- the coefficient for the forward difference.--- Initial step is assumed to be "1"-bezierToForwardDifferenceCoeff-    :: CubicBezier-    -> V2 ForwardDifferenceCoefficient-bezierToForwardDifferenceCoeff (CubicBezier x y z w) = V2 xCoeffs yCoeffs-  where-    xCoeffs = ForwardDifferenceCoefficient { _fdA = ax, _fdB = bx, _fdC = cx }-    yCoeffs = ForwardDifferenceCoefficient { _fdA = ay, _fdB = by, _fdC = cy }--    V2 ax ay = w ^-^ x-    V2 bx by = (w ^-^ z ^* 2 ^+^ y) ^* 6-    V2 cx cy = (w ^-^ z ^* 3 ^+^ y ^* 3 ^-^ x) ^* 6--halveFDCoefficients :: ForwardDifferenceCoefficient -> ForwardDifferenceCoefficient-halveFDCoefficients (ForwardDifferenceCoefficient a b c) =-    ForwardDifferenceCoefficient { _fdA = a', _fdB = b', _fdC = c' }-  where-    c' = c * 0.125-    b' = b * 0.25 - c'-    a' = (a - b') * 0.5--updateForwardDifferencing :: ForwardDifferenceCoefficient -> ForwardDifferenceCoefficient-updateForwardDifferencing (ForwardDifferenceCoefficient a b c) =-  ForwardDifferenceCoefficient (a + b) (b + c) c--updatePointsAndCoeff :: (Applicative f', Applicative f, Additive f)-                     => f' (f Float) -> f' (f ForwardDifferenceCoefficient)-                     -> (f' (f Float), f' (f ForwardDifferenceCoefficient))-updatePointsAndCoeff pts coeffs =-    (advancePoint <$> pts <*> coeffs, fmap updateForwardDifferencing <$> coeffs)-  where-    fstOf (ForwardDifferenceCoefficient a _ _) = a-    advancePoint v c = v ^+^ (fstOf <$> c)---estimateFDStepCount :: CubicBezier -> Int-estimateFDStepCount (CubicBezier p0 p1 p2 p3) =-  toInt $ maximum [p0 `qd` p1, p2 `qd` p3, (p0 `qd` p2) / 4, (p1 `qd` p3) / 4]-  where-    toInt = scale . frexp . max 1 . (18 *)-    scale (_, r) = (r + 1) `div` 2---fixIter :: Int -> (a -> a) -> a -> a-fixIter count f = go count-  where-    go 0 a = a-    go n a = go (n-1) $ f a--isPointInImage :: MutableImage s a -> Point -> Bool-isPointInImage MutableImage { mutableImageWidth = w, mutableImageHeight = h } (V2 x y) =-   0 <= x && x < fromIntegral w && 0 <= y && y < fromIntegral h--isCubicBezierOutsideImage :: MutableImage s a -> CubicBezier -> Bool-isCubicBezierOutsideImage img (CubicBezier a b c d) =-  not $ isIn a || isIn b || isIn c || isIn d-  where isIn = isPointInImage img--isCubicBezierInImage :: MutableImage s a -> CubicBezier -> Bool-isCubicBezierInImage img (CubicBezier a b c d) =-    isIn a && isIn b && isIn c && isIn d-  where isIn = isPointInImage img---- | Rasterize a cubic bezier curve using the Fast Forward Diffrence--- algorithm.-rasterizerCubicBezier :: (PrimMonad m, ModulablePixel px, BiSampleable src px)-                      => src -> CubicBezier-                      -> Float -> Float-                      -> Float -> Float-                      -> DrawContext m px ()-{-# SPECIALIZE INLINE-  rasterizerCubicBezier :: (ParametricValues PixelRGBA8) -> CubicBezier-                        -> Float -> Float-                        -> Float -> Float-                        -> DrawContext (ST s) PixelRGBA8 () #-}-rasterizerCubicBezier source bez uStart vStart uEnd vEnd = do-  canvas <- get-  let !baseFfd = bezierToForwardDifferenceCoeff bez-      !shiftCount = estimateFDStepCount bez-      maxStepCount :: Int-      maxStepCount = 1 `unsafeShiftL` shiftCount-      !(V2 (ForwardDifferenceCoefficient ax' bx' cx)-           (ForwardDifferenceCoefficient ay' by' cy)) =-               fixIter shiftCount halveFDCoefficients <$> baseFfd--      !(V2 _du dv) = (V2 uEnd vEnd ^-^ V2 uStart vStart) ^/ fromIntegral maxStepCount-      !(V2 xStart yStart) = _cBezierX0 bez-      -      go !currentStep _ _ _ _ _ _ _ | currentStep >= maxStepCount = return ()-      go !currentStep !ax !bx !ay !by !x !y !v = do-        let !color = interpolate source uStart v-        plotOpaquePixel canvas color (floor x) (floor y)-        go (currentStep + 1)-            (ax + bx) (bx + cx)-            (ay + by) (by + cy)-            (x  + ax) (y  + ay)-            (v  + dv)--      goUnsafe !currentStep _ _ _ _ _ _ _ | currentStep >= maxStepCount = return ()-      goUnsafe !currentStep !ax !bx !ay !by !x !y !v = do-        let !color = interpolate source uStart v-        unsafePlotOpaquePixel canvas color (floor x) (floor y)-        goUnsafe (currentStep + 1)-            (ax + bx) (bx + cx)-            (ay + by) (by + cy)-            (x  + ax) (y  + ay)-            (v  + dv)--  if isCubicBezierOutsideImage canvas bez then-    return ()-  else if isCubicBezierInImage canvas bez then-    lift $ goUnsafe 0 ax' bx' ay' by' xStart yStart vStart-  else-    lift $ go 0 ax' bx' ay' by' xStart yStart vStart---- | Rasterize a coon patch using the Fast Forward Diffrence algorithm,--- likely to be faster than the subdivision one.-rasterizeCoonPatch :: (PrimMonad m, ModulablePixel px, BiSampleable src px)-                    => CoonPatch src -> DrawContext m px ()-{-# SPECIALIZE rasterizeCoonPatch :: CoonPatch (ParametricValues PixelRGBA8)-                                  -> DrawContext (ST s) PixelRGBA8 () #-}-rasterizeCoonPatch = rasterizeTensorPatch . toTensorPatch---- | Rasterize a tensor patch using the Fast Forward Diffrence algorithm,--- likely to be faster than the subdivision one.-rasterizeTensorPatch :: (PrimMonad m, ModulablePixel px, BiSampleable src px)-                     => TensorPatch src -> DrawContext m px ()-{-# SPECIALIZE rasterizeTensorPatch :: TensorPatch (ParametricValues PixelRGBA8)-                                    -> DrawContext (ST s) PixelRGBA8 () #-}-rasterizeTensorPatch TensorPatch { .. } =-    go maxStepCount basePoints ffCoeff 0-  where-    !curves = V4 _curve0 _curve1 _curve2 _curve3-    !shiftStep = maximum $ estimateFDStepCount <$> [_curve0, _curve1, _curve2, _curve3]-    -    !basePoints = _cBezierX0 <$> curves-    !ffCoeff =-      fmap (fixIter shiftStep halveFDCoefficients) . bezierToForwardDifferenceCoeff <$> curves-    -    maxStepCount :: Int-    !maxStepCount = 1 `unsafeShiftL` shiftStep--    !du = 1 / fromIntegral maxStepCount-    -    toBezier (V4 a b c d) = CubicBezier a b c d-    -    go 0 _pts _coeffs _uvStart = return ()-    go i !pts !coeffs !ut = do-      let (newPoints, newCoeff) = updatePointsAndCoeff pts coeffs-      rasterizerCubicBezier _tensorValues (toBezier pts) ut 0 ut 1-      go (i - 1) newPoints newCoeff (ut + du)--frexp :: Float -> (Float, Int)-frexp x-   | isNaN x = error "NaN given to frexp"-   | isInfinite x = error "infinity given to frexp"-   | otherwise  = go x 0-  where-    go s e-      | s >= 1.0 = go (s / 2) (e + 1)-      | s < 0.5 = go (s * 2) (e - 1)-      | otherwise = (s, e)-+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE RecordWildCards #-}
+module Graphics.Rasterific.CubicBezier.FastForwardDifference
+    ( ForwardDifferenceCoefficient( .. )
+    , bezierToForwardDifferenceCoeff
+    , rasterizerCubicBezier
+    , rasterizeTensorPatch
+    , rasterizeCoonPatch
+    , estimateFDStepCount
+    ) where
+
+import Control.Monad.Primitive( PrimMonad )
+import Control.Monad.State( lift, get )
+import Control.Monad.ST( ST )
+import Data.Bits( unsafeShiftL )
+
+import Codec.Picture( PixelRGBA8 )
+import Codec.Picture.Types( MutableImage( .. ) )
+
+import Graphics.Rasterific.Compositor
+import Graphics.Rasterific.Immediate
+import Graphics.Rasterific.Types
+import Graphics.Rasterific.Linear
+import Graphics.Rasterific.BiSampleable
+import Graphics.Rasterific.PatchTypes
+import Graphics.Rasterific.Shading
+
+data ForwardDifferenceCoefficient = ForwardDifferenceCoefficient
+    { _fdA :: {-# UNPACK #-} !Float
+    , _fdB :: {-# UNPACK #-} !Float
+    , _fdC :: {-# UNPACK #-} !Float
+    }
+
+-- | Given a cubic curve, return the initial step size and
+-- the coefficient for the forward difference.
+-- Initial step is assumed to be "1"
+bezierToForwardDifferenceCoeff
+    :: CubicBezier
+    -> V2 ForwardDifferenceCoefficient
+bezierToForwardDifferenceCoeff (CubicBezier x y z w) = V2 xCoeffs yCoeffs
+  where
+    xCoeffs = ForwardDifferenceCoefficient { _fdA = ax, _fdB = bx, _fdC = cx }
+    yCoeffs = ForwardDifferenceCoefficient { _fdA = ay, _fdB = by, _fdC = cy }
+
+    V2 ax ay = w ^-^ x
+    V2 bx by = (w ^-^ z ^* 2 ^+^ y) ^* 6
+    V2 cx cy = (w ^-^ z ^* 3 ^+^ y ^* 3 ^-^ x) ^* 6
+
+halveFDCoefficients :: ForwardDifferenceCoefficient -> ForwardDifferenceCoefficient
+halveFDCoefficients (ForwardDifferenceCoefficient a b c) =
+    ForwardDifferenceCoefficient { _fdA = a', _fdB = b', _fdC = c' }
+  where
+    c' = c * 0.125
+    b' = b * 0.25 - c'
+    a' = (a - b') * 0.5
+
+updateForwardDifferencing :: ForwardDifferenceCoefficient -> ForwardDifferenceCoefficient
+updateForwardDifferencing (ForwardDifferenceCoefficient a b c) =
+  ForwardDifferenceCoefficient (a + b) (b + c) c
+
+updatePointsAndCoeff :: (Applicative f', Applicative f, Additive f)
+                     => f' (f Float) -> f' (f ForwardDifferenceCoefficient)
+                     -> (f' (f Float), f' (f ForwardDifferenceCoefficient))
+updatePointsAndCoeff pts coeffs =
+    (advancePoint <$> pts <*> coeffs, fmap updateForwardDifferencing <$> coeffs)
+  where
+    fstOf (ForwardDifferenceCoefficient a _ _) = a
+    advancePoint v c = v ^+^ (fstOf <$> c)
+
+
+estimateFDStepCount :: CubicBezier -> Int
+estimateFDStepCount (CubicBezier p0 p1 p2 p3) =
+  toInt $ maximum [p0 `qd` p1, p2 `qd` p3, (p0 `qd` p2) / 4, (p1 `qd` p3) / 4]
+  where
+    toInt = scale . frexp . max 1 . (18 *)
+    scale (_, r) = (r + 1) `div` 2
+
+
+fixIter :: Int -> (a -> a) -> a -> a
+fixIter count f = go count
+  where
+    go 0 a = a
+    go n a = go (n-1) $ f a
+
+isPointInImage :: MutableImage s a -> Point -> Bool
+isPointInImage MutableImage { mutableImageWidth = w, mutableImageHeight = h } (V2 x y) =
+   0 <= x && x < fromIntegral w && 0 <= y && y < fromIntegral h
+
+isCubicBezierOutsideImage :: MutableImage s a -> CubicBezier -> Bool
+isCubicBezierOutsideImage img (CubicBezier a b c d) =
+  not $ isIn a || isIn b || isIn c || isIn d
+  where isIn = isPointInImage img
+
+isCubicBezierInImage :: MutableImage s a -> CubicBezier -> Bool
+isCubicBezierInImage img (CubicBezier a b c d) =
+    isIn a && isIn b && isIn c && isIn d
+  where isIn = isPointInImage img
+
+-- | Rasterize a cubic bezier curve using the Fast Forward Diffrence
+-- algorithm.
+rasterizerCubicBezier :: (PrimMonad m, ModulablePixel px, BiSampleable src px)
+                      => src -> CubicBezier
+                      -> Float -> Float
+                      -> Float -> Float
+                      -> DrawContext m px ()
+{-# SPECIALIZE INLINE
+  rasterizerCubicBezier :: (ParametricValues PixelRGBA8) -> CubicBezier
+                        -> Float -> Float
+                        -> Float -> Float
+                        -> DrawContext (ST s) PixelRGBA8 () #-}
+rasterizerCubicBezier source bez uStart vStart uEnd vEnd = do
+  canvas <- get
+  let !baseFfd = bezierToForwardDifferenceCoeff bez
+      !shiftCount = estimateFDStepCount bez
+      maxStepCount :: Int
+      maxStepCount = 1 `unsafeShiftL` shiftCount
+      !(V2 (ForwardDifferenceCoefficient ax' bx' cx)
+           (ForwardDifferenceCoefficient ay' by' cy)) =
+               fixIter shiftCount halveFDCoefficients <$> baseFfd
+
+      !(V2 _du dv) = (V2 uEnd vEnd ^-^ V2 uStart vStart) ^/ fromIntegral maxStepCount
+      !(V2 xStart yStart) = _cBezierX0 bez
+      
+      go !currentStep _ _ _ _ _ _ _ | currentStep >= maxStepCount = return ()
+      go !currentStep !ax !bx !ay !by !x !y !v = do
+        let !color = interpolate source uStart v
+        plotOpaquePixel canvas color (floor x) (floor y)
+        go (currentStep + 1)
+            (ax + bx) (bx + cx)
+            (ay + by) (by + cy)
+            (x  + ax) (y  + ay)
+            (v  + dv)
+
+      goUnsafe !currentStep _ _ _ _ _ _ _ | currentStep >= maxStepCount = return ()
+      goUnsafe !currentStep !ax !bx !ay !by !x !y !v = do
+        let !color = interpolate source uStart v
+        unsafePlotOpaquePixel canvas color (floor x) (floor y)
+        goUnsafe (currentStep + 1)
+            (ax + bx) (bx + cx)
+            (ay + by) (by + cy)
+            (x  + ax) (y  + ay)
+            (v  + dv)
+
+  if isCubicBezierOutsideImage canvas bez then
+    return ()
+  else if isCubicBezierInImage canvas bez then
+    lift $ goUnsafe 0 ax' bx' ay' by' xStart yStart vStart
+  else
+    lift $ go 0 ax' bx' ay' by' xStart yStart vStart
+
+-- | Rasterize a coon patch using the Fast Forward Diffrence algorithm,
+-- likely to be faster than the subdivision one.
+rasterizeCoonPatch :: (PrimMonad m, ModulablePixel px, BiSampleable src px)
+                    => CoonPatch src -> DrawContext m px ()
+{-# SPECIALIZE rasterizeCoonPatch :: CoonPatch (ParametricValues PixelRGBA8)
+                                  -> DrawContext (ST s) PixelRGBA8 () #-}
+rasterizeCoonPatch = rasterizeTensorPatch . toTensorPatch
+
+-- | Rasterize a tensor patch using the Fast Forward Diffrence algorithm,
+-- likely to be faster than the subdivision one.
+rasterizeTensorPatch :: (PrimMonad m, ModulablePixel px, BiSampleable src px)
+                     => TensorPatch src -> DrawContext m px ()
+{-# SPECIALIZE rasterizeTensorPatch :: TensorPatch (ParametricValues PixelRGBA8)
+                                    -> DrawContext (ST s) PixelRGBA8 () #-}
+rasterizeTensorPatch TensorPatch { .. } =
+    go maxStepCount basePoints ffCoeff 0
+  where
+    !curves = V4 _curve0 _curve1 _curve2 _curve3
+    !shiftStep = maximum $ estimateFDStepCount <$> [_curve0, _curve1, _curve2, _curve3]
+    
+    !basePoints = _cBezierX0 <$> curves
+    !ffCoeff =
+      fmap (fixIter shiftStep halveFDCoefficients) . bezierToForwardDifferenceCoeff <$> curves
+    
+    maxStepCount :: Int
+    !maxStepCount = 1 `unsafeShiftL` shiftStep
+
+    !du = 1 / fromIntegral maxStepCount
+    
+    toBezier (V4 a b c d) = CubicBezier a b c d
+    
+    go 0 _pts _coeffs _uvStart = return ()
+    go i !pts !coeffs !ut = do
+      let (newPoints, newCoeff) = updatePointsAndCoeff pts coeffs
+      rasterizerCubicBezier _tensorValues (toBezier pts) ut 0 ut 1
+      go (i - 1) newPoints newCoeff (ut + du)
+
+frexp :: Float -> (Float, Int)
+frexp x
+   | isNaN x = error "NaN given to frexp"
+   | isInfinite x = error "infinity given to frexp"
+   | otherwise  = go x 0
+  where
+    go s e
+      | s >= 1.0 = go (s / 2) (e + 1)
+      | s < 0.5 = go (s * 2) (e - 1)
+      | otherwise = (s, e)
+
src/Graphics/Rasterific/Patch.hs view
@@ -1,597 +1,609 @@-{-# LANGUAGE CPP #-}-{-# LANGUAGE BangPatterns #-}-{-# LANGUAGE RecordWildCards #-}-{-# LANGUAGE FlexibleInstances #-}-{-# LANGUAGE UndecidableInstances #-}-{-# LANGUAGE DeriveFunctor #-}-{-# LANGUAGE FlexibleContexts #-}-{-# LANGUAGE TypeFamilies #-}-{-# LANGUAGE ViewPatterns #-}-{-# LANGUAGE ScopedTypeVariables #-}-{-# LANGUAGE MultiParamTypeClasses #-}--- | Implementation using--- "An efficient algorithm for subdivising linear Coons surfaces"--- C.Yao and J.Rokne--- Computer aided design 8 (1991) 291-303-module Graphics.Rasterific.Patch-    ( -- * Types-      CoonPatch( .. )-    , TensorPatch( .. )-    , ParametricValues( .. )-    , PatchInterpolation( .. )-    , CoonColorWeight-    , Subdivided( .. )-    , InterpolablePixel--      -- * Rendering functions--      -- ** Using Fast Forward Differences-    , rasterizeTensorPatch -    , rasterizeCoonPatch-    , renderImageMesh-    , renderCoonMesh-    , renderCoonMeshBicubic--      -- ** Subdivision patch rendering-    , renderCoonPatch-    , renderCoonPatchAtDeepness-    , renderTensorPatch-    , renderTensorPatchAtDeepness--      -- * Debugging-    , DebugOption( .. )-    , defaultDebug-    , drawCoonPatchOutline-    , debugDrawCoonPatch-    , debugDrawTensorPatch-    , parametricBase--      -- * Manipulation-    , subdividePatch-    , subdivideTensorPatch-    , horizontalTensorSubdivide-    , transposePatch-    )  where--#if !MIN_VERSION_base(4,8,0)-import Control.Applicative( Applicative( pure, (<*>) ), (<$>) )-import Data.Foldable( Foldable( foldMap ) )-#endif--import Control.Monad.Free( liftF )-import Control.Monad( when, forM_ )-import Control.Monad.Primitive( PrimMonad )-import Data.Monoid( Sum( .. ) )-import Graphics.Rasterific.Types-import Graphics.Rasterific.CubicBezier-import Graphics.Rasterific.CubicBezier.FastForwardDifference-import Graphics.Rasterific.Operators-import Graphics.Rasterific.Linear-import Graphics.Rasterific.Compositor-import Graphics.Rasterific.ComplexPrimitive-import Graphics.Rasterific.Line( lineFromPath )-import Graphics.Rasterific.Immediate-import Graphics.Rasterific.BiSampleable-import Graphics.Rasterific.PatchTypes-import Graphics.Rasterific.MeshPatch-import Graphics.Rasterific.Command--import Codec.Picture.Types( PixelRGBA8( .. ) )---- @---  North    ----->     East---      +--------------+---      |      0       |---    ^ |              | |---    | |3            1| |---    | |              | v---      |      2       |---      +--------------+---  West    <-----      South--- @---estimateCoonSubdivision :: CoonPatch px -> Int-estimateCoonSubdivision CoonPatch { .. } = min 8 $-    maximum $ estimateFDStepCount <$> [_north, _west, _south, _east]--estimateTensorSubdivision :: TensorPatch px -> Int-estimateTensorSubdivision p = min 8 $-  maximum $ estimateFDStepCount <$> (fmap ($ p) axx ++ fmap ($ t) axx)-    where-     axx = [_curve0, _curve1, _curve2, _curve3]-     t = transposePatch p { _tensorValues = parametricBase }--meanValue :: ParametricValues UV -> UV-meanValue = (^* 0.25) . getSum . foldMap Sum---- | Horizontally divides the parametric plane------ @---  N    midNorthEast   E---      +-------+------+---      |0      :     1|---      |       :      |---      | Left  :Right |---      |       :      |---      |3      :     2|---      +-------+------+---  W    midSouthWest   S--- @-subdivideHorizontal :: ParametricValues UV -> (ParametricValues UV, ParametricValues UV)-subdivideHorizontal ParametricValues { .. } = (l, r) where-  midNorthEast = _northValue `midPoint` _eastValue-  midSouthWest = _westValue `midPoint` _southValue--  l = ParametricValues-    { _northValue = _northValue-    , _eastValue = midNorthEast-    , _southValue = midSouthWest-    , _westValue = _westValue-    }--  r = ParametricValues-    { _northValue = midNorthEast-    , _eastValue = _eastValue-    , _southValue = _southValue-    , _westValue = midSouthWest-    }---- | Create UVPatch information for each new quadrant-subdivideWeights :: UVPatch -> Subdivided UVPatch-subdivideWeights values = Subdivided { .. } where-  ParametricValues-    { _northValue = north-    , _eastValue = east-    , _southValue = south-    , _westValue = west-    } = values--  --  N       midNorth    E-  --      +-------+------+-  --      |0      :     1|-  --   mid|   grid:Mid   |-  --  West+=======:======+ midEast-  --      |       :      |-  --      |3      :     2|-  --      +-------+------+-  --  W       midSouth    S-  midNorthValue = north `midPoint` east-  midWestValue = north `midPoint` west-  midSoutValue = west `midPoint` south-  midEastValue = east `midPoint` south--  gridMidValue = midSoutValue `midPoint` midNorthValue--  _northWest = ParametricValues-    { _northValue = north-    , _eastValue = midNorthValue-    , _southValue = gridMidValue-    , _westValue = midWestValue-    }--  _northEast = ParametricValues-    { _northValue = midNorthValue-    , _eastValue = east-    , _southValue = midEastValue-    , _westValue = gridMidValue-    }--  _southWest = ParametricValues-    { _northValue = midWestValue-    , _eastValue  = gridMidValue-    , _southValue = midSoutValue-    , _westValue = west-    }-  -  _southEast = ParametricValues-    { _northValue = gridMidValue-    , _eastValue = midEastValue-    , _southValue = south-    , _westValue = midSoutValue-    }--westCurveOfPatch :: TensorPatch px -> CubicBezier-westCurveOfPatch TensorPatch-  { _curve0 = CubicBezier c0 _ _ _-  , _curve1 = CubicBezier c1 _ _ _-  , _curve2 = CubicBezier c2 _ _ _-  , _curve3 = CubicBezier c3 _ _ _-  } = CubicBezier c0 c1 c2 c3--eastCurveOfPatch :: TensorPatch px -> CubicBezier-eastCurveOfPatch TensorPatch-  { _curve0 = CubicBezier _ _ _ c0-  , _curve1 = CubicBezier _ _ _ c1-  , _curve2 = CubicBezier _ _ _ c2-  , _curve3 = CubicBezier _ _ _ c3-  } = CubicBezier c0 c1 c2 c3---- | Swap vertical/horizontal orientation of a tensor patch-transposePatch :: TensorPatch (ParametricValues a) -> TensorPatch (ParametricValues a)-transposePatch TensorPatch-  { _curve0 = CubicBezier c00 c01 c02 c03-  , _curve1 = CubicBezier c10 c11 c12 c13-  , _curve2 = CubicBezier c20 c21 c22 c23-  , _curve3 = CubicBezier c30 c31 c32 c33-  , _tensorValues = values-  } = TensorPatch-    { _curve0 = CubicBezier c00 c10 c20 c30-    , _curve1 = CubicBezier c01 c11 c21 c31-    , _curve2 = CubicBezier c02 c12 c22 c32-    , _curve3 = CubicBezier c03 c13 c23 c33-    , _tensorValues = transposeParametricValues values-    }----- | Perform an operation like:------ @---    o--------o--------o--------o---    |        |        |        |---    |        |        |        |---    |        |        |        |---    o--------o--------o--------o---    |        |        |        |---    |        |        |        |---    |        |        |        |---    o--------o--------o--------o---    |        |        |        |---    |        |        |        |---    |        |        |        |---    o--------o--------o--------o---    |        |        |        |---    |        |        |        |---    |        |        |        |---    o--------o--------o--------o------       to (more or less)------    o----*---o----*----o----*---o---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    o----*---o----*----o----*---o---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    o----*---o----*----o----*---o---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    o----*---o----*----o----*---o---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    |    |   |    |    |    |   |---    o----*---o----*----o----*---o---    <------------><------------->---       Left            Right--- @----horizontalTensorSubdivide :: TensorPatch UVPatch -> (TensorPatch UVPatch, TensorPatch UVPatch)-horizontalTensorSubdivide p = (TensorPatch l0 l1 l2 l3 vl, TensorPatch r0 r1 r2 r3 vr) where-  (l0, r0) = divideCubicBezier $ _curve0 p-  (l1, r1) = divideCubicBezier $ _curve1 p-  (l2, r2) = divideCubicBezier $ _curve2 p-  (l3, r3) = divideCubicBezier $ _curve3 p-  (vl, vr) = subdivideHorizontal $ _tensorValues p---- | Subdivide a tensor patch into 4 new quadrant.--- Perform twice the horizontal subdivision with a transposition.-subdivideTensorPatch :: TensorPatch UVPatch -> Subdivided (TensorPatch UVPatch)-subdivideTensorPatch p = subdivided where-  (west, east) = horizontalTensorSubdivide p-  (northWest, southWest) = horizontalTensorSubdivide $ transposePatch west-  (northEast, southEast) = horizontalTensorSubdivide $ transposePatch east-  subdivided = Subdivided-    { _northWest = northWest-    , _northEast = northEast-    , _southWest = southWest-    , _southEast = southEast-    }--basePointOfCoonPatch :: CoonPatch (ParametricValues px) -> [(Point, px)]-basePointOfCoonPatch CoonPatch-    { _north = CubicBezier a _ _ b-    , _south = CubicBezier c _ _ d-    , _coonValues = ParametricValues { .. }-    } = [(a, _northValue), (b, _eastValue), (c, _southValue), (d, _westValue)]--controlPointOfCoonPatch :: CoonPatch px -> [Point]-controlPointOfCoonPatch CoonPatch-    { _north = CubicBezier _ a b _-    , _east  = CubicBezier _ c d _-    , _south = CubicBezier _ e f _-    , _west  = CubicBezier _ g h _-    } = [a, b, c, d, e, f, g, h]---- | Store the new generated information after subdivision--- in 4 quadrants.-data Subdivided a = Subdivided-  { _northWest :: !a -- ^ Upper left-  , _northEast :: !a -- ^ Upper right-  , _southWest :: !a -- ^ Lower left-  , _southEast :: !a -- ^ Lower right-  }---- | Split a coon patch into four new quadrants-subdividePatch :: CoonPatch UVPatch -> Subdivided (CoonPatch UVPatch)-subdividePatch patch = Subdivided-    { _northWest = northWest-    , _northEast = northEast-    , _southWest = southWest-    , _southEast = southEast-    } where-  north@(CubicBezier nw _ _ ne) = _north patch-  south@(CubicBezier se _ _ sw) = _south patch--  midNorthLinear = nw `midPoint` ne-  midSouthLinear = sw `midPoint` se-  midWestLinear = nw `midPoint` sw-  midEastLinear = ne `midPoint` se--  -- These points are to calculate S_C and S_D-  (northLeft@(CubicBezier _ _ _ midNorth), northRight) = divideCubicBezier north-  (southRight, southLeft@(CubicBezier midSouth _ _ _ )) = divideCubicBezier south-  (westBottom, westTop@(CubicBezier midWest _ _ _)) = divideCubicBezier $ _west patch-  (eastTop@(CubicBezier _ _ _ midEast), eastBottom) = divideCubicBezier $ _east patch--  -- This points are to calculate S_B-  midNorthSouth = north `midCurve` south-  midEastWest = _east patch `midCurve` _west patch --  (splitNorthSouthTop, splitNorthSouthBottom) =-      divideCubicBezier $ combine-        midEastWest-        (midNorth `straightLine` midSouth)-        (midNorthLinear `straightLine` midSouthLinear)--  (splitWestEastLeft, splitWestEastRight) =-      divideCubicBezier $ combine-        midNorthSouth-        (midWest `straightLine` midEast)-        (midWestLinear `straightLine` midEastLinear)--  weights = subdivideWeights $ _coonValues patch--  northWest = CoonPatch-    { _west = westTop-    , _north = northLeft-    , _east = splitNorthSouthTop-    , _south = inverseBezier splitWestEastLeft-    , _coonValues = _northWest weights-    }--  northEast = CoonPatch-    { _west = inverseBezier splitNorthSouthTop-    , _north = northRight-    , _east = eastTop-    , _south = inverseBezier splitWestEastRight-    , _coonValues = _northEast weights-    }--  southWest = CoonPatch-    { _west = westBottom-    , _north = splitWestEastLeft-    , _east = splitNorthSouthBottom-    , _south = southLeft-    , _coonValues = _southWest weights-    }--  southEast = CoonPatch-    { _west = inverseBezier splitNorthSouthBottom-    , _north = splitWestEastRight-    , _east = eastBottom-    , _south = southRight-    , _coonValues = _southEast weights-    }----- | We must reinverse some bezier curve to match the global--- direction-inverseBezier :: CubicBezier -> CubicBezier-inverseBezier (CubicBezier a b c d) = CubicBezier d c b a---- | Calculate the new cubic bezier using S-combine :: CubicBezier -> CubicBezier -> CubicBezier -> CubicBezier-combine (CubicBezier a1 b1 c1 d1)-        (CubicBezier a2 b2 c2 d2)-        (CubicBezier a3 b3 c3 d3) =-  CubicBezier (a1 ^+^ a2 ^-^ a3)-              (b1 ^+^ b2 ^-^ b3)-              (c1 ^+^ c2 ^-^ c3)-              (d1 ^+^ d2 ^-^ d3)---straightLine :: Point -> Point -> CubicBezier-straightLine a b = CubicBezier a p1 p2 b where-  p1 = lerp (1/3) b a-  p2 = lerp (2/3) b a----- | The curves in the coon patch are inversed!-midCurve :: CubicBezier -> CubicBezier -> CubicBezier-midCurve (CubicBezier a b c d) (CubicBezier d' c' b' a') =-  CubicBezier-    (a `midPoint` a')-    (b `midPoint` b')-    (c `midPoint` c')-    (d `midPoint` d')---- | Draw the 4 bezier spline representing the boundary of a coon patch.-drawCoonPatchOutline :: CoonPatch px -> Drawing pxb ()-drawCoonPatchOutline CoonPatch { .. } =-  liftF $ Stroke 2 JoinRound (CapRound, CapRound) prims ()-  where-    prims = toPrimitives [_north, _east, _south, _west]--pointsOf :: PointFoldable v => v -> [Point]-pointsOf = foldPoints (flip (:)) []---- | Used to describe how to debug print a coon/tensort patch.-data DebugOption = DebugOption-  { _drawControlMesh    :: !Bool-  , _drawBaseVertices   :: !Bool-  , _drawControVertices :: !Bool-  , _colorVertices      :: !Bool-  , _drawOutline        :: !Bool-  , _outlineColor       :: !PixelRGBA8-  , _controlMeshColor   :: !PixelRGBA8-  , _vertexColor        :: !PixelRGBA8-  , _controlColor       :: !PixelRGBA8-  }---- | Default options drawing nearly everything.-defaultDebug :: DebugOption-defaultDebug = DebugOption-  { _drawControlMesh    = True-  , _drawBaseVertices   = True-  , _drawControVertices = True-  , _drawOutline        = True-  , _colorVertices      = False-  , _outlineColor       = PixelRGBA8 0 0 0 255-  , _controlMeshColor   = PixelRGBA8 50 50 128 255-  , _vertexColor        = PixelRGBA8 20 20 40 255-  , _controlColor       = PixelRGBA8 20 20 40 255-  }---- | Helper function drawing many information about a coon patch.-debugDrawCoonPatch :: DebugOption -> CoonPatch (ParametricValues PixelRGBA8)-                   -> Drawing PixelRGBA8 ()-debugDrawCoonPatch DebugOption { .. } patch@(CoonPatch { .. }) = do-  let stroker v = liftF $ Stroke 2 JoinRound (CapRound, CapRound) v ()-      fill sub = liftF $ Fill FillWinding sub ()-      setColor' c inner = liftF $ SetTexture (SolidTexture c) inner ()-  when _drawOutline $-    setColor' _outlineColor (drawCoonPatchOutline patch)--  when _drawBaseVertices $-    forM_ (basePointOfCoonPatch patch) $ \(p, c) ->-       if not _colorVertices then-         setColor' _vertexColor (stroker $ circle p 4)-       else do-         setColor' c . fill $ circle p 4-         setColor' _vertexColor . stroker $ circle p 5--  when _drawControVertices $-    forM_ (controlPointOfCoonPatch patch) $ \p ->-       setColor' _controlColor . stroker $ circle p 4--  let controlDraw = stroker . toPrimitives . lineFromPath . pointsOf-  when _drawControlMesh $-    setColor' _controlMeshColor $ do-        mapM_ controlDraw [_north, _east, _west, _south]---- | Helper function drawing many information about a tensor patch.-debugDrawTensorPatch :: DebugOption -> TensorPatch (ParametricValues px)-                     -> Drawing PixelRGBA8 ()-debugDrawTensorPatch DebugOption { .. } p = do-  let stroker v = liftF $ Stroke 2 JoinRound (CapRound, CapRound) v ()-      setColor' c inner =-          liftF $ SetTexture (SolidTexture c) inner ()-      p' = transposePatch p--  when _drawOutline $-    setColor' _outlineColor $-        mapM_ (stroker . toPrimitives)-            [ _curve0 p, _curve1 p, _curve2 p, _curve3 p-            , _curve0 p', _curve1 p', _curve2 p', _curve3 p']--  when _drawBaseVertices   $-    setColor' _vertexColor $-        forM_ (pointsOf p) $ \pp -> stroker $ circle pp 4--  let controlDraw = stroker . toPrimitives . lineFromPath . pointsOf-  when _drawControlMesh $-    setColor' _controlMeshColor $ do-        mapM_ controlDraw-            [ _curve0 p, _curve1 p, _curve2 p, _curve3 p-            , _curve0 p', _curve1 p', _curve2 p', _curve3 p']---- | Define the unit square in [0, 1]^2-parametricBase :: UVPatch-parametricBase = ParametricValues-  { _northValue = V2 0 0-  , _eastValue  = V2 1 0-  , _southValue = V2 1 1-  , _westValue  = V2 0 1-  }---- | Render a simple coon mesh, with only color on the vertices.-renderCoonMesh :: forall m px.-                  (PrimMonad m, RenderablePixel px, BiSampleable (ParametricValues px) px)-               => MeshPatch px -> DrawContext m px ()-renderCoonMesh = mapM_ (rasterizeTensorPatch . toTensorPatch) . coonPatchesOf---- | Render a coon mesh but using cubic interpolation for the color.-renderCoonMeshBicubic :: forall m px.-                         ( PrimMonad m-                         , RenderablePixel px-                         , BiSampleable (CubicCoefficient px) px)-                      => MeshPatch px -> DrawContext m px ()-renderCoonMeshBicubic =-  mapM_ (rasterizeTensorPatch . toTensorPatch)-    . cubicCoonPatchesOf-    . calculateMeshColorDerivative---- | Render an mesh patch by interpolating accross an image.-renderImageMesh :: PrimMonad m-                => MeshPatch (ImageMesh PixelRGBA8) -> DrawContext m PixelRGBA8 ()-renderImageMesh = mapM_ (rasterizeTensorPatch . toTensorPatch) . imagePatchesOf---- | Render a coon patch using the subdivision algorithm (potentially slower--- and less precise in case of image mesh.-renderCoonPatch :: forall m interp px.-                   (PrimMonad m, RenderablePixel px, BiSampleable interp px)-                => CoonPatch interp -> DrawContext m px ()-renderCoonPatch p = renderCoonPatchAtDeepness (estimateCoonSubdivision p) p---- | Render a coon patch using the subdivision algorithm (potentially slower--- and less precise in case of image mesh). You can provide a max deepness-renderCoonPatchAtDeepness-    :: forall m interp px.-       (PrimMonad m, RenderablePixel px, BiSampleable interp px)-    => Int              -- ^ Maximum subdivision deepness-    -> CoonPatch interp-    -> DrawContext m px ()-renderCoonPatchAtDeepness maxDeepness originalPatch = go maxDeepness basePatch where-  baseColors = _coonValues originalPatch--  basePatch = originalPatch { _coonValues = parametricBase }--  drawPatchUniform CoonPatch { .. } = fillWithTextureNoAA FillWinding texture geometry where-    geometry = toPrim <$> [_north, _east, _south, _west]-    !(V2 u v) =meanValue _coonValues-    !texture = SolidTexture $ interpolate baseColors u v--  go 0 patch = drawPatchUniform patch-  go depth (subdividePatch -> Subdivided { .. }) =-    let d = depth - (1 :: Int) in-    go d _northWest >> go d _northEast >> go d _southWest >> go d _southEast--renderTensorPatch :: forall m sampled px. -                     (PrimMonad m, RenderablePixel px, BiSampleable sampled px)-                  => TensorPatch sampled -> DrawContext m px ()-renderTensorPatch p = renderTensorPatchAtDeepness (estimateTensorSubdivision p) p---- | Render a tensor patch using the subdivision algorithm (potentially slower--- and less precise in case of image mesh.-renderTensorPatchAtDeepness-  :: forall m sampled px. -     (PrimMonad m, RenderablePixel px, BiSampleable sampled px)-  => Int -> TensorPatch sampled -> DrawContext m px ()-renderTensorPatchAtDeepness maxDeepness originalPatch = go maxDeepness basePatch where-  baseColors = _tensorValues originalPatch--  basePatch = originalPatch { _tensorValues = parametricBase }--  drawPatchUniform p = fillWithTextureNoAA FillWinding texture geometry where-    geometry = toPrim <$> [_curve0 p, westCurveOfPatch p, _curve3 p, eastCurveOfPatch p]-    !(V2 u v) = meanValue $ _tensorValues p-    texture = SolidTexture $ interpolate baseColors u v--  go 0 patch = drawPatchUniform patch-  go depth (subdivideTensorPatch -> Subdivided { .. }) =-    let d = depth - (1 :: Int) in-    go d _northWest >> go d _northEast >> go d _southWest >> go d _southEast-+{-# LANGUAGE CPP #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE DeriveFunctor #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE ViewPatterns #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+-- | Implementation using
+-- "An efficient algorithm for subdivising linear Coons surfaces"
+-- C.Yao and J.Rokne
+-- Computer aided design 8 (1991) 291-303
+module Graphics.Rasterific.Patch
+    ( -- * Types
+      CoonPatch( .. )
+    , TensorPatch( .. )
+    , ParametricValues( .. )
+    , PatchInterpolation( .. )
+    , CoonColorWeight
+    , Subdivided( .. )
+    , InterpolablePixel
+
+      -- * Rendering functions
+
+      -- ** Using Fast Forward Differences
+    , rasterizeTensorPatch 
+    , rasterizeCoonPatch
+    , renderImageMesh
+    , renderCoonMesh
+    , renderCoonMeshBicubic
+
+      -- ** Subdivision patch rendering
+    , renderCoonPatch
+    , renderCoonPatchAtDeepness
+    , renderTensorPatch
+    , renderTensorPatchAtDeepness
+
+      -- * Debugging
+    , DebugOption( .. )
+    , defaultDebug
+    , drawCoonPatchOutline
+    , debugDrawCoonPatch
+    , debugDrawTensorPatch
+    , parametricBase
+
+      -- * Manipulation
+    , subdividePatch
+    , subdivideTensorPatch
+    , horizontalTensorSubdivide
+    , transposePatch
+    )  where
+
+#if !MIN_VERSION_base(4,8,0)
+import Control.Applicative( Applicative( pure, (<*>) ), (<$>) )
+import Data.Foldable( Foldable( foldMap ) )
+#endif
+
+import Control.Monad.Free( liftF )
+import Control.Monad( when, forM_ )
+import Control.Monad.Primitive( PrimMonad )
+import Data.Monoid( Sum( .. ) )
+import Graphics.Rasterific.Types
+import Graphics.Rasterific.CubicBezier
+import Graphics.Rasterific.CubicBezier.FastForwardDifference
+import Graphics.Rasterific.Operators
+import Graphics.Rasterific.Linear
+import Graphics.Rasterific.Compositor
+import Graphics.Rasterific.ComplexPrimitive
+import Graphics.Rasterific.Line( lineFromPath )
+import Graphics.Rasterific.Immediate
+import Graphics.Rasterific.BiSampleable
+import Graphics.Rasterific.PatchTypes
+import Graphics.Rasterific.MeshPatch
+import Graphics.Rasterific.Command
+
+import Codec.Picture.Types( PixelRGBA8( .. ) )
+
+-- @
+--  North    ----->     East
+--      +--------------+
+--      |      0       |
+--    ^ |              | |
+--    | |3            1| |
+--    | |              | v
+--      |      2       |
+--      +--------------+
+--  West    <-----      South
+-- @
+
+
+-- TODO: find a new way to calculate that...
+maxColorDeepness :: forall px. InterpolablePixel px => ParametricValues px -> Int
+maxColorDeepness values = ceiling $ log (maxDelta * range) / log 2 where
+  range = maxRepresentable (Proxy :: Proxy px)
+  maxDelta = 
+    maximum [ maxDistance north east
+            , maxDistance east south
+            , maxDistance south west
+            , maxDistance west north]
+  ParametricValues { _westValue = west, _northValue = north
+                   , _southValue = south, _eastValue = east } = values
+
+estimateCoonSubdivision :: CoonPatch px -> Int
+estimateCoonSubdivision CoonPatch { .. } = min 8 $
+    maximum $ estimateFDStepCount <$> [_north, _west, _south, _east]
+
+estimateTensorSubdivision :: TensorPatch px -> Int
+estimateTensorSubdivision p = min 8 $
+  maximum $ estimateFDStepCount <$> (fmap ($ p) axx ++ fmap ($ t) axx)
+    where
+     axx = [_curve0, _curve1, _curve2, _curve3]
+     t = transposePatch p { _tensorValues = parametricBase }
+
+meanValue :: ParametricValues UV -> UV
+meanValue = (^* 0.25) . getSum . foldMap Sum
+
+-- | Horizontally divides the parametric plane
+--
+-- @
+--  N    midNorthEast   E
+--      +-------+------+
+--      |0      :     1|
+--      |       :      |
+--      | Left  :Right |
+--      |       :      |
+--      |3      :     2|
+--      +-------+------+
+--  W    midSouthWest   S
+-- @
+subdivideHorizontal :: ParametricValues UV -> (ParametricValues UV, ParametricValues UV)
+subdivideHorizontal ParametricValues { .. } = (l, r) where
+  midNorthEast = _northValue `midPoint` _eastValue
+  midSouthWest = _westValue `midPoint` _southValue
+
+  l = ParametricValues
+    { _northValue = _northValue
+    , _eastValue = midNorthEast
+    , _southValue = midSouthWest
+    , _westValue = _westValue
+    }
+
+  r = ParametricValues
+    { _northValue = midNorthEast
+    , _eastValue = _eastValue
+    , _southValue = _southValue
+    , _westValue = midSouthWest
+    }
+
+-- | Create UVPatch information for each new quadrant
+subdivideWeights :: UVPatch -> Subdivided UVPatch
+subdivideWeights values = Subdivided { .. } where
+  ParametricValues
+    { _northValue = north
+    , _eastValue = east
+    , _southValue = south
+    , _westValue = west
+    } = values
+
+  --  N       midNorth    E
+  --      +-------+------+
+  --      |0      :     1|
+  --   mid|   grid:Mid   |
+  --  West+=======:======+ midEast
+  --      |       :      |
+  --      |3      :     2|
+  --      +-------+------+
+  --  W       midSouth    S
+  midNorthValue = north `midPoint` east
+  midWestValue = north `midPoint` west
+  midSoutValue = west `midPoint` south
+  midEastValue = east `midPoint` south
+
+  gridMidValue = midSoutValue `midPoint` midNorthValue
+
+  _northWest = ParametricValues
+    { _northValue = north
+    , _eastValue = midNorthValue
+    , _southValue = gridMidValue
+    , _westValue = midWestValue
+    }
+
+  _northEast = ParametricValues
+    { _northValue = midNorthValue
+    , _eastValue = east
+    , _southValue = midEastValue
+    , _westValue = gridMidValue
+    }
+
+  _southWest = ParametricValues
+    { _northValue = midWestValue
+    , _eastValue  = gridMidValue
+    , _southValue = midSoutValue
+    , _westValue = west
+    }
+  
+  _southEast = ParametricValues
+    { _northValue = gridMidValue
+    , _eastValue = midEastValue
+    , _southValue = south
+    , _westValue = midSoutValue
+    }
+
+westCurveOfPatch :: TensorPatch px -> CubicBezier
+westCurveOfPatch TensorPatch
+  { _curve0 = CubicBezier c0 _ _ _
+  , _curve1 = CubicBezier c1 _ _ _
+  , _curve2 = CubicBezier c2 _ _ _
+  , _curve3 = CubicBezier c3 _ _ _
+  } = CubicBezier c0 c1 c2 c3
+
+eastCurveOfPatch :: TensorPatch px -> CubicBezier
+eastCurveOfPatch TensorPatch
+  { _curve0 = CubicBezier _ _ _ c0
+  , _curve1 = CubicBezier _ _ _ c1
+  , _curve2 = CubicBezier _ _ _ c2
+  , _curve3 = CubicBezier _ _ _ c3
+  } = CubicBezier c0 c1 c2 c3
+
+-- | Swap vertical/horizontal orientation of a tensor patch
+transposePatch :: TensorPatch (ParametricValues a) -> TensorPatch (ParametricValues a)
+transposePatch TensorPatch
+  { _curve0 = CubicBezier c00 c01 c02 c03
+  , _curve1 = CubicBezier c10 c11 c12 c13
+  , _curve2 = CubicBezier c20 c21 c22 c23
+  , _curve3 = CubicBezier c30 c31 c32 c33
+  , _tensorValues = values
+  } = TensorPatch
+    { _curve0 = CubicBezier c00 c10 c20 c30
+    , _curve1 = CubicBezier c01 c11 c21 c31
+    , _curve2 = CubicBezier c02 c12 c22 c32
+    , _curve3 = CubicBezier c03 c13 c23 c33
+    , _tensorValues = transposeParametricValues values
+    }
+
+
+-- | Perform an operation like:
+--
+-- @
+--    o--------o--------o--------o
+--    |        |        |        |
+--    |        |        |        |
+--    |        |        |        |
+--    o--------o--------o--------o
+--    |        |        |        |
+--    |        |        |        |
+--    |        |        |        |
+--    o--------o--------o--------o
+--    |        |        |        |
+--    |        |        |        |
+--    |        |        |        |
+--    o--------o--------o--------o
+--    |        |        |        |
+--    |        |        |        |
+--    |        |        |        |
+--    o--------o--------o--------o
+--
+--       to (more or less)
+--
+--    o----*---o----*----o----*---o
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    o----*---o----*----o----*---o
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    o----*---o----*----o----*---o
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    o----*---o----*----o----*---o
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    |    |   |    |    |    |   |
+--    o----*---o----*----o----*---o
+--    <------------><------------->
+--       Left            Right
+-- @
+--
+horizontalTensorSubdivide :: TensorPatch UVPatch -> (TensorPatch UVPatch, TensorPatch UVPatch)
+horizontalTensorSubdivide p = (TensorPatch l0 l1 l2 l3 vl, TensorPatch r0 r1 r2 r3 vr) where
+  (l0, r0) = divideCubicBezier $ _curve0 p
+  (l1, r1) = divideCubicBezier $ _curve1 p
+  (l2, r2) = divideCubicBezier $ _curve2 p
+  (l3, r3) = divideCubicBezier $ _curve3 p
+  (vl, vr) = subdivideHorizontal $ _tensorValues p
+
+-- | Subdivide a tensor patch into 4 new quadrant.
+-- Perform twice the horizontal subdivision with a transposition.
+subdivideTensorPatch :: TensorPatch UVPatch -> Subdivided (TensorPatch UVPatch)
+subdivideTensorPatch p = subdivided where
+  (west, east) = horizontalTensorSubdivide p
+  (northWest, southWest) = horizontalTensorSubdivide $ transposePatch west
+  (northEast, southEast) = horizontalTensorSubdivide $ transposePatch east
+  subdivided = Subdivided
+    { _northWest = northWest
+    , _northEast = northEast
+    , _southWest = southWest
+    , _southEast = southEast
+    }
+
+basePointOfCoonPatch :: CoonPatch (ParametricValues px) -> [(Point, px)]
+basePointOfCoonPatch CoonPatch
+    { _north = CubicBezier a _ _ b
+    , _south = CubicBezier c _ _ d
+    , _coonValues = ParametricValues { .. }
+    } = [(a, _northValue), (b, _eastValue), (c, _southValue), (d, _westValue)]
+
+controlPointOfCoonPatch :: CoonPatch px -> [Point]
+controlPointOfCoonPatch CoonPatch
+    { _north = CubicBezier _ a b _
+    , _east  = CubicBezier _ c d _
+    , _south = CubicBezier _ e f _
+    , _west  = CubicBezier _ g h _
+    } = [a, b, c, d, e, f, g, h]
+
+-- | Store the new generated information after subdivision
+-- in 4 quadrants.
+data Subdivided a = Subdivided
+  { _northWest :: !a -- ^ Upper left
+  , _northEast :: !a -- ^ Upper right
+  , _southWest :: !a -- ^ Lower left
+  , _southEast :: !a -- ^ Lower right
+  }
+
+-- | Split a coon patch into four new quadrants
+subdividePatch :: CoonPatch UVPatch -> Subdivided (CoonPatch UVPatch)
+subdividePatch patch = Subdivided
+    { _northWest = northWest
+    , _northEast = northEast
+    , _southWest = southWest
+    , _southEast = southEast
+    } where
+  north@(CubicBezier nw _ _ ne) = _north patch
+  south@(CubicBezier se _ _ sw) = _south patch
+
+  midNorthLinear = nw `midPoint` ne
+  midSouthLinear = sw `midPoint` se
+  midWestLinear = nw `midPoint` sw
+  midEastLinear = ne `midPoint` se
+
+  -- These points are to calculate S_C and S_D
+  (northLeft@(CubicBezier _ _ _ midNorth), northRight) = divideCubicBezier north
+  (southRight, southLeft@(CubicBezier midSouth _ _ _ )) = divideCubicBezier south
+  (westBottom, westTop@(CubicBezier midWest _ _ _)) = divideCubicBezier $ _west patch
+  (eastTop@(CubicBezier _ _ _ midEast), eastBottom) = divideCubicBezier $ _east patch
+
+  -- This points are to calculate S_B
+  midNorthSouth = north `midCurve` south
+  midEastWest = _east patch `midCurve` _west patch 
+
+  (splitNorthSouthTop, splitNorthSouthBottom) =
+      divideCubicBezier $ combine
+        midEastWest
+        (midNorth `straightLine` midSouth)
+        (midNorthLinear `straightLine` midSouthLinear)
+
+  (splitWestEastLeft, splitWestEastRight) =
+      divideCubicBezier $ combine
+        midNorthSouth
+        (midWest `straightLine` midEast)
+        (midWestLinear `straightLine` midEastLinear)
+
+  weights = subdivideWeights $ _coonValues patch
+
+  northWest = CoonPatch
+    { _west = westTop
+    , _north = northLeft
+    , _east = splitNorthSouthTop
+    , _south = inverseBezier splitWestEastLeft
+    , _coonValues = _northWest weights
+    }
+
+  northEast = CoonPatch
+    { _west = inverseBezier splitNorthSouthTop
+    , _north = northRight
+    , _east = eastTop
+    , _south = inverseBezier splitWestEastRight
+    , _coonValues = _northEast weights
+    }
+
+  southWest = CoonPatch
+    { _west = westBottom
+    , _north = splitWestEastLeft
+    , _east = splitNorthSouthBottom
+    , _south = southLeft
+    , _coonValues = _southWest weights
+    }
+
+  southEast = CoonPatch
+    { _west = inverseBezier splitNorthSouthBottom
+    , _north = splitWestEastRight
+    , _east = eastBottom
+    , _south = southRight
+    , _coonValues = _southEast weights
+    }
+
+
+-- | We must reinverse some bezier curve to match the global
+-- direction
+inverseBezier :: CubicBezier -> CubicBezier
+inverseBezier (CubicBezier a b c d) = CubicBezier d c b a
+
+-- | Calculate the new cubic bezier using S
+combine :: CubicBezier -> CubicBezier -> CubicBezier -> CubicBezier
+combine (CubicBezier a1 b1 c1 d1)
+        (CubicBezier a2 b2 c2 d2)
+        (CubicBezier a3 b3 c3 d3) =
+  CubicBezier (a1 ^+^ a2 ^-^ a3)
+              (b1 ^+^ b2 ^-^ b3)
+              (c1 ^+^ c2 ^-^ c3)
+              (d1 ^+^ d2 ^-^ d3)
+
+
+straightLine :: Point -> Point -> CubicBezier
+straightLine a b = CubicBezier a p1 p2 b where
+  p1 = lerp (1/3) b a
+  p2 = lerp (2/3) b a
+
+
+-- | The curves in the coon patch are inversed!
+midCurve :: CubicBezier -> CubicBezier -> CubicBezier
+midCurve (CubicBezier a b c d) (CubicBezier d' c' b' a') =
+  CubicBezier
+    (a `midPoint` a')
+    (b `midPoint` b')
+    (c `midPoint` c')
+    (d `midPoint` d')
+
+-- | Draw the 4 bezier spline representing the boundary of a coon patch.
+drawCoonPatchOutline :: CoonPatch px -> Drawing pxb ()
+drawCoonPatchOutline CoonPatch { .. } =
+  liftF $ Stroke 2 JoinRound (CapRound, CapRound) prims ()
+  where
+    prims = toPrimitives [_north, _east, _south, _west]
+
+pointsOf :: PointFoldable v => v -> [Point]
+pointsOf = foldPoints (flip (:)) []
+
+-- | Used to describe how to debug print a coon/tensort patch.
+data DebugOption = DebugOption
+  { _drawControlMesh    :: !Bool
+  , _drawBaseVertices   :: !Bool
+  , _drawControVertices :: !Bool
+  , _colorVertices      :: !Bool
+  , _drawOutline        :: !Bool
+  , _outlineColor       :: !PixelRGBA8
+  , _controlMeshColor   :: !PixelRGBA8
+  , _vertexColor        :: !PixelRGBA8
+  , _controlColor       :: !PixelRGBA8
+  }
+
+-- | Default options drawing nearly everything.
+defaultDebug :: DebugOption
+defaultDebug = DebugOption
+  { _drawControlMesh    = True
+  , _drawBaseVertices   = True
+  , _drawControVertices = True
+  , _drawOutline        = True
+  , _colorVertices      = False
+  , _outlineColor       = PixelRGBA8 0 0 0 255
+  , _controlMeshColor   = PixelRGBA8 50 50 128 255
+  , _vertexColor        = PixelRGBA8 20 20 40 255
+  , _controlColor       = PixelRGBA8 20 20 40 255
+  }
+
+-- | Helper function drawing many information about a coon patch.
+debugDrawCoonPatch :: DebugOption -> CoonPatch (ParametricValues PixelRGBA8)
+                   -> Drawing PixelRGBA8 ()
+debugDrawCoonPatch DebugOption { .. } patch@(CoonPatch { .. }) = do
+  let stroker v = liftF $ Stroke 2 JoinRound (CapRound, CapRound) v ()
+      fill sub = liftF $ Fill FillWinding sub ()
+      setColor' c inner = liftF $ SetTexture (SolidTexture c) inner ()
+  when _drawOutline $
+    setColor' _outlineColor (drawCoonPatchOutline patch)
+
+  when _drawBaseVertices $
+    forM_ (basePointOfCoonPatch patch) $ \(p, c) ->
+       if not _colorVertices then
+         setColor' _vertexColor (stroker $ circle p 4)
+       else do
+         setColor' c . fill $ circle p 4
+         setColor' _vertexColor . stroker $ circle p 5
+
+  when _drawControVertices $
+    forM_ (controlPointOfCoonPatch patch) $ \p ->
+       setColor' _controlColor . stroker $ circle p 4
+
+  let controlDraw = stroker . toPrimitives . lineFromPath . pointsOf
+  when _drawControlMesh $
+    setColor' _controlMeshColor $ do
+        mapM_ controlDraw [_north, _east, _west, _south]
+
+-- | Helper function drawing many information about a tensor patch.
+debugDrawTensorPatch :: DebugOption -> TensorPatch (ParametricValues px)
+                     -> Drawing PixelRGBA8 ()
+debugDrawTensorPatch DebugOption { .. } p = do
+  let stroker v = liftF $ Stroke 2 JoinRound (CapRound, CapRound) v ()
+      setColor' c inner =
+          liftF $ SetTexture (SolidTexture c) inner ()
+      p' = transposePatch p
+
+  when _drawOutline $
+    setColor' _outlineColor $
+        mapM_ (stroker . toPrimitives)
+            [ _curve0 p, _curve1 p, _curve2 p, _curve3 p
+            , _curve0 p', _curve1 p', _curve2 p', _curve3 p']
+
+  when _drawBaseVertices   $
+    setColor' _vertexColor $
+        forM_ (pointsOf p) $ \pp -> stroker $ circle pp 4
+
+  let controlDraw = stroker . toPrimitives . lineFromPath . pointsOf
+  when _drawControlMesh $
+    setColor' _controlMeshColor $ do
+        mapM_ controlDraw
+            [ _curve0 p, _curve1 p, _curve2 p, _curve3 p
+            , _curve0 p', _curve1 p', _curve2 p', _curve3 p']
+
+-- | Define the unit square in [0, 1]^2
+parametricBase :: UVPatch
+parametricBase = ParametricValues
+  { _northValue = V2 0 0
+  , _eastValue  = V2 1 0
+  , _southValue = V2 1 1
+  , _westValue  = V2 0 1
+  }
+
+-- | Render a simple coon mesh, with only color on the vertices.
+renderCoonMesh :: forall m px.
+                  (PrimMonad m, RenderablePixel px, BiSampleable (ParametricValues px) px)
+               => MeshPatch px -> DrawContext m px ()
+renderCoonMesh = mapM_ (rasterizeTensorPatch . toTensorPatch) . coonPatchesOf
+
+-- | Render a coon mesh but using cubic interpolation for the color.
+renderCoonMeshBicubic :: forall m px.
+                         ( PrimMonad m
+                         , RenderablePixel px
+                         , BiSampleable (CubicCoefficient px) px)
+                      => MeshPatch px -> DrawContext m px ()
+renderCoonMeshBicubic =
+  mapM_ (rasterizeTensorPatch . toTensorPatch)
+    . cubicCoonPatchesOf
+    . calculateMeshColorDerivative
+
+-- | Render an mesh patch by interpolating accross an image.
+renderImageMesh :: PrimMonad m
+                => MeshPatch (ImageMesh PixelRGBA8) -> DrawContext m PixelRGBA8 ()
+renderImageMesh = mapM_ (rasterizeTensorPatch . toTensorPatch) . imagePatchesOf
+
+-- | Render a coon patch using the subdivision algorithm (potentially slower
+-- and less precise in case of image mesh.
+renderCoonPatch :: forall m interp px.
+                   (PrimMonad m, RenderablePixel px, BiSampleable interp px)
+                => CoonPatch interp -> DrawContext m px ()
+renderCoonPatch p = renderCoonPatchAtDeepness (estimateCoonSubdivision p) p
+
+-- | Render a coon patch using the subdivision algorithm (potentially slower
+-- and less precise in case of image mesh). You can provide a max deepness
+renderCoonPatchAtDeepness
+    :: forall m interp px.
+       (PrimMonad m, RenderablePixel px, BiSampleable interp px)
+    => Int              -- ^ Maximum subdivision deepness
+    -> CoonPatch interp
+    -> DrawContext m px ()
+renderCoonPatchAtDeepness maxDeepness originalPatch = go maxDeepness basePatch where
+  baseColors = _coonValues originalPatch
+
+  basePatch = originalPatch { _coonValues = parametricBase }
+
+  drawPatchUniform CoonPatch { .. } = fillWithTextureNoAA FillWinding texture geometry where
+    geometry = toPrim <$> [_north, _east, _south, _west]
+    !(V2 u v) =meanValue _coonValues
+    !texture = SolidTexture $ interpolate baseColors u v
+
+  go 0 patch = drawPatchUniform patch
+  go depth (subdividePatch -> Subdivided { .. }) =
+    let d = depth - (1 :: Int) in
+    go d _northWest >> go d _northEast >> go d _southWest >> go d _southEast
+
+renderTensorPatch :: forall m sampled px. 
+                     (PrimMonad m, RenderablePixel px, BiSampleable sampled px)
+                  => TensorPatch sampled -> DrawContext m px ()
+renderTensorPatch p = renderTensorPatchAtDeepness (estimateTensorSubdivision p) p
+
+-- | Render a tensor patch using the subdivision algorithm (potentially slower
+-- and less precise in case of image mesh.
+renderTensorPatchAtDeepness
+  :: forall m sampled px. 
+     (PrimMonad m, RenderablePixel px, BiSampleable sampled px)
+  => Int -> TensorPatch sampled -> DrawContext m px ()
+renderTensorPatchAtDeepness maxDeepness originalPatch = go maxDeepness basePatch where
+  baseColors = _tensorValues originalPatch
+
+  basePatch = originalPatch { _tensorValues = parametricBase }
+
+  drawPatchUniform p = fillWithTextureNoAA FillWinding texture geometry where
+    geometry = toPrim <$> [_curve0 p, westCurveOfPatch p, _curve3 p, eastCurveOfPatch p]
+    !(V2 u v) = meanValue $ _tensorValues p
+    texture = SolidTexture $ interpolate baseColors u v
+
+  go 0 patch = drawPatchUniform patch
+  go depth (subdivideTensorPatch -> Subdivided { .. }) =
+    let d = depth - (1 :: Int) in
+    go d _northWest >> go d _northEast >> go d _southWest >> go d _southEast
+