diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Revision history for Mondrian
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
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+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Mondrian.cabal b/Mondrian.cabal
new file mode 100644
--- /dev/null
+++ b/Mondrian.cabal
@@ -0,0 +1,67 @@
+cabal-version: >=1.10
+-- Initial package description 'Mondrian.cabal' generated by 'cabal init'.
+-- For further documentation, see http://haskell.org/cabal/users-guide/
+
+name: Mondrian
+version: 0.1.0.0
+synopsis: Renders backgrounds & borders
+-- description:
+homepage: https://argonaut-constellation.org/
+-- bug-reports:
+license: GPL-3
+license-file: LICENSE
+author: Adrian Cochrane
+maintainer: ~alcinnz/Mondrian@todo.argonaut-constellation.org
+-- copyright:
+category: Graphics
+build-type: Simple
+extra-source-files: CHANGELOG.md
+
+library
+ exposed-modules: Graphics.Rendering.Rect,
+ Graphics.Rendering.Rect.Backgrounds,
+ Graphics.Rendering.Rect.Border,
+ Graphics.Rendering.Rect.Image,
+ Graphics.Rendering.Rect.CSS,
+ Graphics.Rendering.Rect.CSS.Colour,
+ Graphics.Rendering.Rect.CSS.Backgrounds,
+ Graphics.Rendering.Rect.CSS.Border
+ other-modules: Graphics.Rendering.Rect.Types
+ -- other-extensions:
+ build-depends: base >=4.13 && <5, stylist-traits >= 0.1.3.1 && < 1,
+ css-syntax, colour >= 2.3.6 && < 3, scientific, text,
+ bytestring, typograffiti >=0.2 && <0.4, linear,
+ gl, vector, mtl,
+ unordered-containers>=0.2 && <1, JuicyPixels >=3.0 && <4
+ hs-source-dirs: lib
+ default-language: Haskell2010
+
+ ghc-options: -Wall
+
+executable Mondrian
+ main-is: Main.hs
+ -- other-modules:
+ -- other-extensions:
+ build-depends: base >=4.13 && <5, Mondrian, sdl2 >= 2.5.4, gl, linear,
+ stylist-traits, text, css-syntax, JuicyPixels
+ hs-source-dirs: app
+ default-language: Haskell2010
+
+ ghc-options: -Wall
+
+executable Convert
+ main-is: Convert.hs
+ build-depends: base >= 4.13 && <5, JuicyPixels
+ hs-source-dirs: app
+ default-language: Haskell2010
+
+ ghc-options: -Wall
+
+test-suite Mondrian-test
+ default-language: Haskell2010
+ type: exitcode-stdio-1.0
+ hs-source-dirs: test
+ main-is: MyLibTest.hs
+ build-depends: base >=4.13 && <5
+
+ ghc-options: -Wall
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/app/Convert.hs b/app/Convert.hs
new file mode 100644
--- /dev/null
+++ b/app/Convert.hs
@@ -0,0 +1,29 @@
+module Main where
+
+import Codec.Picture (readImage, savePngImage, DynamicImage(..), Image, PixelF)
+import Codec.Picture.Types (promoteImage, convertImage, pixelMap)
+import System.Environment (getArgs)
+
+main :: IO ()
+main = do
+ [path] <- getArgs
+ Right img <- readImage path
+ savePngImage "out.png" $ convertDyn img
+
+-- Convert pixels to some flavour of RGBA
+convertDyn :: DynamicImage -> DynamicImage
+convertDyn (ImageY8 img) = ImageRGBA8 $ promoteImage img
+convertDyn (ImageY16 img) = ImageRGBA16 $ promoteImage img
+convertDyn (ImageY32 img) =
+ ImageRGBF $ promoteImage (pixelMap fromIntegral img :: Image PixelF)
+convertDyn (ImageYF img) = ImageRGBF $ promoteImage img
+convertDyn (ImageYA8 img) = ImageRGBA8 $ promoteImage img
+convertDyn (ImageYA16 img) = ImageRGBA16 $ promoteImage img
+convertDyn (ImageRGB8 img) = ImageRGB8 img
+convertDyn (ImageRGB16 img) = ImageRGB16 img
+convertDyn (ImageRGBF img) = ImageRGBF img
+convertDyn (ImageRGBA8 img) = ImageRGBA8 img
+convertDyn (ImageRGBA16 img) = ImageRGBA16 img
+convertDyn (ImageYCbCr8 img) = ImageRGB8 $ convertImage img
+convertDyn (ImageCMYK8 img) = ImageRGB8 $ convertImage img
+convertDyn (ImageCMYK16 img) = ImageRGB16 $ convertImage img
diff --git a/app/Main.hs b/app/Main.hs
new file mode 100644
--- /dev/null
+++ b/app/Main.hs
@@ -0,0 +1,90 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Main where
+
+import Graphics.Rendering.Rect
+import Stylist.Parse (parseProperties')
+import Stylist (PropertyParser(..))
+import Data.Text (Text, pack, unpack)
+import Data.CSS.Syntax.Tokens (tokenize, serialize, Token(Whitespace))
+
+import SDL hiding (trace)
+import Graphics.GL.Core32
+import System.Environment (getArgs)
+
+import Data.Function (fix)
+import Control.Monad (unless)
+import Control.Monad.IO.Class (MonadIO (..))
+
+import Codec.Picture (DynamicImage(..), PixelRGBA8(..),
+ readImage, generateImage)
+
+import Debug.Trace (trace) -- To warn about invalid args
+
+parseStyle :: PropertyParser p => String -> p
+parseStyle syn
+ | (ret, []) <- parseProperties' toks = apply ret
+ | (ret, rest) <- parseProperties' toks =
+ trace ("Extraneous chars: " ++ unpack (serialize rest)) $ apply ret
+ where
+ toks = tokenize $ pack syn
+ apply ((key, val):props)
+ | Just self' <- longhand self self key val' = self'
+ | props'@(_:_) <- shorthand self key val' = apply (props' ++ props)
+ | otherwise = trace ("Unsupported property " ++ unpack key) self
+ where
+ self = apply props
+ val' = filter (/= Whitespace) val
+ apply [] = temp
+
+orthoProjection :: (Fractional a1, Integral a2) => V2 a2 -> M44 a1
+orthoProjection (V2 ww wh) =
+ let (hw,hh) = (fromIntegral ww, fromIntegral wh)
+ in ortho 0 hw hh 0 0 1
+
+main :: IO ()
+main = do
+ SDL.initializeAll
+ args <- getArgs
+ let style :: RectStyle Text
+ style = case args of
+ [] -> trace "Using blank styles, should see blank screen!" temp
+ [arg] -> parseStyle arg
+ (arg:_) -> trace "Extraneous commandline args!" $ parseStyle arg
+
+ let openGL = defaultOpenGL { glProfile = Core Debug 3 3 }
+ wcfg = defaultWindow {
+ windowInitialSize = V2 640 480,
+ windowGraphicsContext = OpenGLContext openGL,
+ windowResizable = True
+ }
+ w <- createWindow "Mondrian" wcfg
+ _ <- glCreateContext w
+
+ atlas <- atlasFromStyles loadImage [style]
+ let style' = styleResolveImages atlas style
+
+ render <- renderRects
+ fix $ \loop -> do
+ events <- fmap eventPayload <$> pollEvents
+ liftIO $ glClearColor 1 1 1 1
+ liftIO $ glClear GL_COLOR_BUFFER_BIT
+
+ sz@(V2 dw dh) <- liftIO $ glGetDrawableSize w
+ liftIO $ glViewport 0 0 (fromIntegral dw) (fromIntegral dh)
+
+ let rect = Rect 0 0 (fromIntegral dw) (fromIntegral dh)
+ rects = Rects (shrink1 rect 150) (shrink1 rect 100) (shrink1 rect 50) rect
+
+ render style' rects $ orthoProjection sz
+
+ liftIO $ glSwapWindow w
+ unless (QuitEvent `elem` events) loop
+
+loadImage :: Text -> IO DynamicImage
+loadImage path = do
+ ret <- readImage $ unpack path
+ return $ case ret of
+ Right x -> x
+ Left _ -> ImageRGBA8 $ generateImage transparent 1 1
+transparent :: p1 -> p2 -> PixelRGBA8
+transparent _ _ = PixelRGBA8 0 0 0 0
diff --git a/lib/Graphics/Rendering/Rect.hs b/lib/Graphics/Rendering/Rect.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect.hs
@@ -0,0 +1,50 @@
+module Graphics.Rendering.Rect(Rect(..), Rects(..), shrink, shrink1, renderRects,
+ RectStyle(..), colour, border,
+ Backgrounds(..), Pattern(..), Resize(..), Length(..), RadialShape(..),
+ Border(..), BorderStyle(..), topColour, rightColour, bottomColour, leftColour,
+ Atlas, buildAtlas, atlasFromStyles, Texture, styleResolveImages) where
+
+import Graphics.Rendering.Rect.CSS
+import Graphics.Rendering.Rect.Backgrounds
+import Graphics.Rendering.Rect.Types
+import Graphics.Rendering.Rect.Image
+import Graphics.Rendering.Rect.Border
+
+import Linear (M44)
+import Control.Monad.IO.Class (MonadIO)
+
+import Codec.Picture (DynamicImage)
+import Data.Text (Text)
+import Data.List (nub)
+
+shrink :: Rect -> Float -> Float -> Float -> Float -> Rect
+shrink self dLeft dTop dRight dBottom =
+ Rect (left self + dLeft) (top self + dTop)
+ (right self - dRight) (bottom self - dBottom)
+shrink1 :: Rect -> Float -> Rect
+shrink1 self d = shrink self d d d d
+
+renderRects :: (MonadIO m, MonadIO n) =>
+ n (RectStyle Texture -> Rects -> M44 Float -> m ())
+renderRects = do
+ bg <- renderBackgrounds
+ frame <- renderBorder
+ return $ \style rects mat -> do
+ bg (backgrounds style) rects mat
+ frame (border style) rects mat
+
+styleResolveImages :: Atlas -> RectStyle Text -> RectStyle Texture
+styleResolveImages atlas self =
+ let textures = map atlasLookup' $ image $ backgrounds self
+ in self { backgrounds = (backgrounds self) { image = textures } }
+ where
+ atlasLookup' None = None
+ atlasLookup' (Img path) = Img $ atlasLookup path atlas
+ atlasLookup' (Linear a b) = Linear a b
+ atlasLookup' (Radial a b cc d) = Radial a b cc d
+ atlasLookup' (Conical a b cc) = Conical a b cc
+
+atlasFromStyles :: MonadIO m =>
+ (Text -> IO DynamicImage) -> [RectStyle Text] -> m Atlas
+atlasFromStyles cb styles =
+ buildAtlas cb $ nub [path | s <- styles, Img path <- image $ backgrounds s]
diff --git a/lib/Graphics/Rendering/Rect/Backgrounds.hs b/lib/Graphics/Rendering/Rect/Backgrounds.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/Backgrounds.hs
@@ -0,0 +1,276 @@
+module Graphics.Rendering.Rect.Backgrounds(Backgrounds(..), Pattern(..),
+ RadialShape(..), Resize(..), Length(..), Extent(..),
+ resolveSize, renderBackgrounds) where
+
+import Graphics.Rendering.Rect.CSS.Backgrounds
+import Graphics.Rendering.Rect.Types
+import Graphics.Rendering.Rect.Image (Texture(texSize), textureSetRepeat)
+import qualified Data.ByteString.Char8 as B8
+import Linear (M44, V2(..))
+
+import Control.Monad.IO.Class (MonadIO(..))
+import Data.Maybe (fromMaybe, listToMaybe)
+import Control.Monad (forM)
+
+baseFragmentShader :: B8.ByteString
+baseFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "out vec4 fcolour;",
+ "uniform vec4 colour;",
+ "void main() { fcolour = colour; }"
+ ]
+
+imageFragmentShader :: B8.ByteString
+imageFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "uniform vec2 pos;",
+ "uniform sampler2D image;",
+ "uniform vec2 size;",
+ "void main() { fcolour = texture(image, coord/size - pos/size); }"
+ ]
+
+linearFragmentShader :: B8.ByteString
+linearFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "uniform vec2 size;",
+ "uniform vec4 stops[10];",
+ "uniform float stopPoints[10];",
+ "uniform int nStops;",
+ "uniform float angle;",
+ "",
+ "void main() {",
+ " vec2 pos = coord/size;", -- Range 0..1
+ " pos -= 0.5; pos *= 2;", -- Range -1..1
+ " float a = pos.x*sin(angle) + pos.y*-cos(angle);", -- Range -1..1
+ " a /= 2; a += 0.5;", -- Range 0..1
+ "",
+ " int i = 0;",
+ -- Workaround for buggy GPU drivers on test machine.
+ " if (1 < nStops - 1 && a > stopPoints[1]) i = 1;",
+ " if (2 < nStops - 1 && a > stopPoints[2]) i = 2;",
+ " if (3 < nStops - 1 && a > stopPoints[3]) i = 3;",
+ " if (4 < nStops - 1 && a > stopPoints[4]) i = 4;",
+ " if (5 < nStops - 1 && a > stopPoints[5]) i = 5;",
+ " if (6 < nStops - 1 && a > stopPoints[6]) i = 6;",
+ " if (7 < nStops - 1 && a > stopPoints[7]) i = 7;",
+ " if (8 < nStops - 1 && a > stopPoints[8]) i = 8;",
+ "",
+ " a = smoothstep(stopPoints[i], stopPoints[i+1], a);",
+ " fcolour = mix(stops[i], stops[i+1], a);",
+ "}"
+ ]
+
+radialFragmentShader :: B8.ByteString
+radialFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "uniform vec2 size;",
+ "uniform vec2 extent;",
+ "uniform vec2 center;",
+ "uniform vec4 stops[10];",
+ "uniform float stopPoints[10];",
+ "uniform int nStops;",
+ "",
+ "void main() {",
+ " float a = distance(coord/extent, center/size) * 2;",
+ "",
+ " int i = 0;",
+ -- Workaround for buggy GPU drivers on test machine.
+ " if (1 < nStops - 1 && a > stopPoints[1]) i = 1;",
+ " if (2 < nStops - 1 && a > stopPoints[2]) i = 2;",
+ " if (3 < nStops - 1 && a > stopPoints[3]) i = 3;",
+ " if (4 < nStops - 1 && a > stopPoints[4]) i = 4;",
+ " if (5 < nStops - 1 && a > stopPoints[5]) i = 5;",
+ " if (6 < nStops - 1 && a > stopPoints[6]) i = 6;",
+ " if (7 < nStops - 1 && a > stopPoints[7]) i = 7;",
+ " if (8 < nStops - 1 && a > stopPoints[8]) i = 8;",
+ "",
+ " a = smoothstep(stopPoints[i], stopPoints[i+1], a);",
+ " fcolour = mix(stops[i], stops[i+1], a);",
+ "}"
+ ]
+circleFragmentShader :: B8.ByteString
+circleFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "uniform vec2 center;",
+ "uniform float radius;",
+ "uniform vec4 stops[10];",
+ "uniform float stopPoints[10];",
+ "uniform int nStops;",
+ "",
+ "void main() {",
+ " float a = distance(coord, center)/radius;",
+ "",
+ " int i = 0;",
+ -- Workaround for buggy GPU drivers on test machine.
+ " if (1 < nStops - 1 && a > stopPoints[1]) i = 1;",
+ " if (2 < nStops - 1 && a > stopPoints[2]) i = 2;",
+ " if (3 < nStops - 1 && a > stopPoints[3]) i = 3;",
+ " if (4 < nStops - 1 && a > stopPoints[4]) i = 4;",
+ " if (5 < nStops - 1 && a > stopPoints[5]) i = 5;",
+ " if (6 < nStops - 1 && a > stopPoints[6]) i = 6;",
+ " if (7 < nStops - 1 && a > stopPoints[7]) i = 7;",
+ " if (8 < nStops - 1 && a > stopPoints[8]) i = 8;",
+ "",
+ " a = smoothstep(stopPoints[i], stopPoints[i+1], a);",
+ " fcolour = mix(stops[i], stops[i+1], a);",
+ "}"
+ ]
+
+conicFragmentShader :: B8.ByteString
+conicFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "uniform vec2 center;",
+ "uniform float angle;",
+ "uniform vec4 stops[10];",
+ "uniform float stopPoints[10];",
+ "uniform int nStops;",
+ "",
+ "void main() {",
+ " vec2 v = coord - center;",
+ " float a = atan(v.x, -v.y) - angle;",
+ " float turn = 2*radians(180);",
+ " a = fract(a/turn);",
+ "",
+ " int i = 0;",
+ -- Workaround for buggy GPU drivers on test machine.
+ " if (1 < nStops - 1 && a > stopPoints[1]) i = 1;",
+ " if (2 < nStops - 1 && a > stopPoints[2]) i = 2;",
+ " if (3 < nStops - 1 && a > stopPoints[3]) i = 3;",
+ " if (4 < nStops - 1 && a > stopPoints[4]) i = 4;",
+ " if (5 < nStops - 1 && a > stopPoints[5]) i = 5;",
+ " if (6 < nStops - 1 && a > stopPoints[6]) i = 6;",
+ " if (7 < nStops - 1 && a > stopPoints[7]) i = 7;",
+ " if (8 < nStops - 1 && a > stopPoints[8]) i = 8;",
+ "",
+ " a = smoothstep(stopPoints[i], stopPoints[i+1], a);",
+ " fcolour = mix(stops[i], stops[i+1], a);",
+ "}"
+ ]
+
+renderBackgrounds :: (MonadIO m, MonadIO n) =>
+ n (Backgrounds Texture -> Rects -> M44 Float -> m ())
+renderBackgrounds = do
+ base <- renderRectWith baseFragmentShader ["colour"]
+ layer <- renderRectWith imageFragmentShader ["size", "pos"]
+ linear <- renderRectWith linearFragmentShader ["size", "angle",
+ "stops", "stopPoints", "nStops"]
+ ellipse <- renderRectWith radialFragmentShader ["size", "extent", "center",
+ "stops", "stopPoints", "nStops"]
+ circle <- renderRectWith circleFragmentShader ["center", "radius",
+ "stops", "stopPoints", "nStops"]
+ conic <- renderRectWith conicFragmentShader ["center", "angle",
+ "stops", "stopPoints", "nStops"]
+ return $ \self a b -> do
+ base [] [c $ background self] (headDef borderBox $ clip self)
+ (headDef paddingBox $ origin self) a b
+ let layers = image self `zip` (clip self ++ repeat borderBox)
+ `zip` (bgSize self ++ repeat (Size Auto Auto))
+ `zip` (origin self ++ repeat paddingBox)
+ `zip` (bgPos self ++ repeat (Absolute 0, Absolute 0))
+ `zip` (bgRepeat self ++ repeat (True, True))
+ _<-forM layers $ \(((((pat0, clip0), size0), origin0), pos0), repeat0) ->
+ case pat0 of
+ None -> return ()
+ Img img0 -> do
+ let sz = resolveSize (size $ clip0 a) (texSize img0) size0
+ let pos' = (v2$l2f' pos0$size$clip0 a) - (v2$l2f' pos0 sz)
+ textureSetRepeat img0 repeat0
+ layer [img0] [u $ v2 sz, u pos'] clip0 origin0 a b
+ Linear angle stops -> let size' = size $ clip0 a in linear [] [
+ u $ v2 $ size', u angle, cs 10 $ map fst stops,
+ us $ ls2fs size' $ map snd $ take 10 stops, u $ length stops
+ ] clip0 origin0 a b
+ -- FIXME: Incorporate resolveEllipseExtent without messing up center
+ Radial Ellipse ext org stops -> let sz@(_,h) = size $ clip0 a in
+ let (org', ext') = resolveEllipseExtent sz org ext in ellipse [] [
+ u $ v2 sz, u $ v2 ext', u $ v2 org', cs 10 $ map fst stops,
+ us $ ls2fs (0,h/2) $ map snd $ take 10 stops, u $ length stops
+ ] clip0 origin0 a b
+ Radial Circle ext org stops -> let sz@(w,h) = size $ clip0 a
+ in let (org', r) = resolveCircleExtent sz org ext in circle [] [
+ u $ v2 org', u r, cs 10 $ map fst stops,
+ us $ ls2fs (0,min w h/2) $ map snd $ take 10 stops,
+ u $ length stops
+ ] clip0 origin0 a b
+ Conical angle org stops -> let sz = size $ clip0 a in conic [] [
+ u $ v2 $ l2f' org sz, u angle, cs 10 $ map fst stops,
+ us $ ls2fs (0,2*pi) $ map snd $ take 10 stops, u $ length stops
+ ] clip0 origin0 a b
+ return ()
+
+headDef :: c -> [c] -> c
+headDef def = fromMaybe def . listToMaybe
+v2 :: (a, a) -> V2 a
+v2 = uncurry V2
+-- Easier to express this algorithm on CPU-side...
+ls2fs :: (Float, Float) -> [Length] -> [Float]
+ls2fs (_,h) ls = resolveAutos 0 $ inner True 0 ls
+ where
+ -- https://drafts.csswg.org/css-images/#color-stop-fixup Step 1.
+ inner True _ (Auto:ls') = Scale 0:inner False 0 ls'
+ inner _ _ [Auto] = [Scale 1]
+ -- Step 2
+ inner _ prev (Scale x:ls') | x < prev = Scale prev:inner False prev ls'
+ inner _ prev (Absolute x:ls') | x/h < prev = Scale prev:inner False prev ls'
+ inner _ _ (Scale x:ls') = Scale x:inner False x ls'
+ inner _ _ (Absolute x:ls') = Absolute x:inner False (x/h) ls'
+ inner _ prev (Auto:ls') = Auto:inner False prev ls'
+ inner _ _ [] = []
+ -- Step 3
+ resolveAutos :: Float -> [Length] -> [Float]
+ resolveAutos _ (Scale x:ls') = x:resolveAutos x ls'
+ resolveAutos _ (Absolute x:ls') = (x/h):resolveAutos (x/h) ls'
+ resolveAutos _ [] = []
+ resolveAutos prev ls0 = [prev + succ i*grad | i <- [0..n - 1]] ++ fs
+ where
+ (autos, ls') = span (==Auto) ls0
+ n = toEnum $ length autos
+ fs = resolveAutos 0 ls' -- Doesn't matter if prev's in another branch...
+ next | (x:_) <- fs = x
+ | otherwise = 1 -- Step 1 should've taken care of this...
+ grad = (next - prev)/(n + 1)
+
+l2f :: Length -> Float -> Float
+l2f Auto x = x/2
+l2f (Scale x) y = x*y
+l2f (Absolute x) _ = x
+l2f' :: (Length, Length) -> (Float, Float) -> (Float, Float)
+l2f' (x,y) (w,h) = (l2f x w, l2f y h)
+
+resolveEllipseExtent :: (Float, Float) -> (Length, Length) -> Extent ->
+ ((Float, Float), (Float, Float))
+resolveEllipseExtent sz@(x',y') pos ext = ((x, y), inner ext)
+ where
+ (x,y) = l2f' pos sz
+ horiz = [x, x' - x]
+ vert = [y, y' - y]
+ inner (Extent s t) = (l2f s x, l2f t y)
+ -- FIXME: How to calculate closest/farthest-corner?
+ -- Spec just says keep this aspect ratio.
+ inner ClosestCorner = (minimum horiz * 2, minimum vert * 2)
+ inner ClosestSide = (minimum horiz * 2, minimum vert * 2)
+ inner FarthestCorner = (maximum horiz * 2, maximum vert * 2)
+ inner FarthestSide = (maximum horiz * 2, maximum vert * 2)
+resolveCircleExtent :: (Float, Float) -> (Length, Length) -> Extent ->
+ ((Float, Float), Float)
+resolveCircleExtent sz@(x',y') pos ext = ((x, y), inner ext)
+ where
+ (x,y) = l2f' pos sz
+ sides = [x, x' - x, y, y' - y]
+ corners = [hypot x y, hypot x $ y'-y, hypot y $ x'-x, hypot (x'-x) (y'-y)]
+ hypot a b = sqrt $ a*a + b*b
+ inner (Extent a _) = l2f a y -- Should be absolute...
+ inner ClosestCorner = minimum corners
+ inner ClosestSide = minimum sides
+ inner FarthestCorner = maximum corners
+ inner FarthestSide = maximum sides
diff --git a/lib/Graphics/Rendering/Rect/Border.hs b/lib/Graphics/Rendering/Rect/Border.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/Border.hs
@@ -0,0 +1,99 @@
+module Graphics.Rendering.Rect.Border(renderBorder, Border(..), BorderStyle(..),
+ topColour, rightColour, bottomColour, leftColour) where
+
+import Graphics.Rendering.Rect.CSS.Border
+import Graphics.Rendering.Rect.Types
+import qualified Data.ByteString.Char8 as B8
+import Control.Monad.IO.Class (MonadIO(..))
+import Linear (M44)
+
+borderFragmentShader :: B8.ByteString
+borderFragmentShader = B8.pack $ unlines [
+ "#version 330 core",
+ "uniform float widths[4];",
+ "uniform vec4 colours[4];",
+ "uniform int styles[5];",
+ "uniform vec2 boxSize;",
+ "in vec2 coord;",
+ "out vec4 fcolour;",
+ "",
+ "const int TOP = 0;",
+ "const int RIGHT = 1;",
+ "const int BOTTOM = 2;",
+ "const int LEFT = 3;",
+ "const int NONE = 4;",
+ "",
+ "const int NOBORDER = 0;",
+ "const int SOLID = 1;",
+ "const int DASHED = 2;",
+ "const int DOTTED = 3;",
+ "const int DOUBLE = 4;",
+ "const int GROOVE = 5;",
+ "const int RIDGE = 6;",
+ "const int INSET = 7;",
+ "const int OUTSET = 8;",
+ "",
+ "bool inTrap(float x, float y, float width, int height, int left, int right) {",
+ " float a = y/widths[height];",
+ " return a*widths[left] <= x && x <= width - widths[right]*a;",
+ "}",
+ "",
+ "void main() {",
+ " int side = NONE;",
+ " if (coord.y < abs(widths[TOP]) &&",
+ " inTrap(coord.x, coord.y, boxSize.x, TOP, LEFT, RIGHT))",
+ " side = TOP;",
+ " else if (coord.x < abs(widths[LEFT]) &&",
+ " inTrap(coord.y, coord.x, boxSize.y, LEFT, TOP, BOTTOM))",
+ " side = LEFT;",
+ " else if (boxSize.x - coord.x < abs(widths[RIGHT]) &&",
+ " inTrap(coord.y, boxSize.x-coord.x, boxSize.y, RIGHT,TOP,BOTTOM))",
+ " side = RIGHT;",
+ " else if (boxSize.y - coord.y < abs(widths[BOTTOM])) side = BOTTOM;",
+ "",
+ " vec2 pos = coord;",
+ " if (side == RIGHT || side == BOTTOM) pos = boxSize - coord;",
+ " if (side == LEFT || side == RIGHT) pos = pos.yx;",
+ "",
+ " int segment = int(floor(pos.x/widths[side]/2));",
+ " float width = widths[side];",
+ " vec2 dotCenter = vec2(segment*width*2 + width, width/2);",
+ " int stroke3 = int(floor(3*pos.y/widths[side]));",
+ " int stroke = int(floor(2*pos.y/widths[side]));",
+ " bool topleft = side == TOP || side == LEFT;",
+ " if (!topleft) stroke = abs(1 - stroke);",
+ " if (styles[side] == SOLID) fcolour = colours[side];",
+ " else if (styles[side] == DASHED)",
+ " fcolour = segment % 2 == 0 ? colours[side] : vec4(0);",
+ " else if (styles[side] == DOTTED)",
+ " fcolour = distance(pos, dotCenter) < widths[side]/2 ?",
+ " colours[side] : vec4(0);",
+ " else if (styles[side] == DOUBLE && stroke3 != 1) fcolour = colours[side];",
+ " else if (styles[side] == GROOVE)",
+ " fcolour = colours[side] + vec4(stroke == 0 ? -0.1 : +0.1);",
+ " else if (styles[side] == RIDGE)",
+ " fcolour = colours[side] + vec4(stroke == 0 ? +0.1 : -0.1);",
+ " else if (styles[side] == INSET)",
+ " fcolour = colours[side] + vec4(topleft ? -0.2 : +0.2);",
+ " else if (styles[side] == OUTSET)",
+ " fcolour = colours[side] + vec4(topleft ? +0.2 : -0.2);",
+ " else fcolour = vec4(0.0);",
+ "}"
+ ]
+
+renderBorder :: (MonadIO m, MonadIO n) => n (Border -> Rects -> M44 Float -> m ())
+renderBorder = do
+ inner <- renderRectWith borderFragmentShader [
+ "widths[0]", "widths[1]", "widths[2]", "widths[3]",
+ "colours[0]", "colours[1]", "colours[2]", "colours[3]",
+ "styles[0]", "styles[1]", "styles[2]", "styles[3]", "styles[4]"]
+ return $ \self rects -> let (b, p) = (borderBox rects, paddingBox rects)
+ in inner [] [
+ u $ top p - top b, u $ right b - right p,
+ u $ bottom b - bottom p, u $ left p - left b,
+ c $ topColour self, c $ rightColour self,
+ c $ bottomColour self, c $ leftColour self,
+ u $ fromEnum $ topStyle self, u $ fromEnum $ rightStyle self,
+ u $ fromEnum $ bottomStyle self, u $ fromEnum $ leftStyle self,
+ u (0 :: Int)
+ ] borderBox borderBox rects
diff --git a/lib/Graphics/Rendering/Rect/CSS.hs b/lib/Graphics/Rendering/Rect/CSS.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/CSS.hs
@@ -0,0 +1,42 @@
+{-# LANGUAGE OverloadedStrings, RecordWildCards, FlexibleInstances #-}
+module Graphics.Rendering.Rect.CSS(RectStyle(..), colour, border) where
+
+import Stylist (PropertyParser(..))
+import Graphics.Rendering.Rect.CSS.Colour (ColourPallet(foreground))
+import Graphics.Rendering.Rect.CSS.Backgrounds (Backgrounds(..))
+import Graphics.Rendering.Rect.CSS.Border (Border(..))
+import Data.Text (Text)
+import Data.Colour(AlphaColour)
+
+data RectStyle img = RectStyle {
+ colours :: ColourPallet,
+ backgrounds :: Backgrounds img,
+ border' :: Border
+} deriving (Eq, Show, Read)
+colour :: RectStyle img -> AlphaColour Float
+colour = foreground . colours
+border :: RectStyle img -> Border
+border self = (border' self) { borderPallet = colours self }
+
+instance PropertyParser (RectStyle Text) where
+ temp = RectStyle { colours = temp, backgrounds = temp, border' = temp }
+ inherit RectStyle {..} = RectStyle {
+ colours = inherit colours, backgrounds = temp, border' = temp
+ }
+ priority RectStyle {..} =
+ priority colours ++ priority backgrounds ++ priority border'
+
+ shorthand self key value
+ | ret@(_:_) <- shorthand (backgrounds self) key value = ret
+ | ret@(_:_) <- shorthand (border self) key value = ret
+ | Just _ <- longhand self self key value = [(key, value)]
+ | otherwise = []
+ longhand parent self key value
+ | Just ret <- longhand (backgrounds parent) { pallet = colours self }
+ (backgrounds self) { pallet = colours self } key value =
+ Just self { backgrounds = ret }
+ | Just ret <- longhand (colours parent) (colours self) key value =
+ Just self { colours = ret }
+ | Just ret <- longhand (border parent) (border self) key value =
+ Just self { border' = ret }
+ | otherwise = Nothing
diff --git a/lib/Graphics/Rendering/Rect/CSS/Backgrounds.hs b/lib/Graphics/Rendering/Rect/CSS/Backgrounds.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/CSS/Backgrounds.hs
@@ -0,0 +1,333 @@
+{-# LANGUAGE OverloadedStrings, FlexibleInstances #-}
+module Graphics.Rendering.Rect.CSS.Backgrounds (Backgrounds(..),
+ Pattern(..), RadialShape(..), Extent(..),
+ Resize(..), Length(..), resolveSize) where
+
+import Stylist (PropertyParser(..), parseUnorderedShorthand, parseOperands)
+import Data.CSS.Syntax.Tokens (Token(..), NumericValue(..))
+import Data.Maybe (isJust, catMaybes)
+import Data.Text (Text)
+import Data.Scientific (scientific, toRealFloat)
+
+import Graphics.Rendering.Rect.CSS.Colour (ColourPallet, parseColour)
+import Data.Colour (AlphaColour, transparent)
+import Graphics.Rendering.Rect.Types (Rects(..), Rect(..))
+
+data Backgrounds img = Backgrounds {
+ pallet :: ColourPallet,
+ background :: C,
+ clip :: [Rects -> Rect],
+ origin :: [Rects -> Rect],
+ image :: [Pattern img],
+ bgPos :: [(Length, Length)],
+ bgSize :: [Resize],
+ bgRepeat :: [(Bool, Bool)]
+} deriving (Eq, Show, Read)
+
+type C = AlphaColour Float
+
+data Pattern img = None | Img img | Linear Float [(C, Length)]
+ | Radial RadialShape Extent (Length, Length) [(C, Length)]
+ | Conical Float (Length, Length) [(C, Length)]
+ deriving (Eq, Show, Read)
+data RadialShape = Circle | Ellipse deriving (Eq, Show, Read)
+data Extent = Extent Length Length | ClosestCorner
+ | ClosestSide | FarthestCorner | FarthestSide deriving (Eq, Show, Read)
+
+-- We need to resolve images before we can compute the actual lengths!
+data Resize = Cover | Contain | Size Length Length deriving (Eq, Show, Read)
+data Length = Absolute Float | Scale Float | Auto deriving (Eq, Show, Read)
+
+instance PropertyParser (Backgrounds Text) where
+ temp = Backgrounds {
+ pallet = temp, background = transparent, clip = [borderBox],
+ image = [None], bgSize = [Size Auto Auto], origin = [paddingBox],
+ bgPos = [(Absolute 0, Absolute 0)], bgRepeat = [(True, True)]
+ }
+ inherit _ = temp
+ priority _ = []
+
+ longhand _ self@Backgrounds{ pallet = c } "background-color" toks
+ | Just ([], val) <- parseColour c toks = Just self { background = val }
+ longhand _ self "background-clip" t | val@(_:_) <- parseCSSList box t =
+ Just self { clip = reverse val }
+ longhand _ self@Backgrounds { pallet = pp } "background-image" t
+ | val@(_:_) <- parseCSSList inner t = Just self { image = reverse val }
+ where
+ inner [Ident "none"] = Just None
+ inner [Ident "initial"] = Just None
+ inner [Url ret] = Just $ Img ret
+ inner [Function "url", String ret, RightParen] = Just $ Img ret
+ inner (Function "linear-gradient":toks)
+ | Just cs@(_:_:_)<-colourStops pp (Comma:toks) = Just $ Linear pi cs
+ inner (Function "linear-gradient":Dimension _ x unit:toks)
+ | Just s <- lookup unit angularUnits,
+ Just cs@(_:_:_) <- colourStops pp toks = Just $ Linear (f x*s) cs
+ inner (Function "linear-gradient":Ident "to":Ident a:Ident b:toks)
+ | Just angle<-corner a b, Just stops@(_:_:_)<-colourStops pp toks =
+ Just $ Linear angle stops
+ | Just angle<-corner b a, Just stops@(_:_:_)<-colourStops pp toks =
+ Just $ Linear angle stops
+ where
+ corner "top" "right" = Just $ 0.25*pi
+ corner "bottom" "right" = Just $ 0.75*pi
+ corner "bottom" "left" = Just $ 1.25*pi
+ corner "top" "left" = Just $ 1.75*pi
+ corner _ _ = Nothing
+ inner (Function "linear-gradient":Ident "to":Ident side:toks)
+ | Just angle <- lookup side [
+ ("top", 0), ("right", pi/2), ("bottom", pi), ("left", pi*1.5)],
+ Just cs@(_:_:_) <- colourStops pp toks = Just $ Linear angle cs
+ inner (Function "radial-gradient":toks)
+ | Just cs@(_:_:_) <- colourStops pp (Comma:toks) =
+ Just $ Radial Ellipse FarthestCorner center cs
+ | (shp, org, ext, ts) <- radArgs toks,
+ Just cs@(_:_:_) <- colourStops pp ts = Just $ Radial shp ext org cs
+ where
+ radArgs (Ident s:Ident "at":ts) | Just shape <- radShape s,
+ Just (org, ts') <- position ts =
+ (shape, org, FarthestCorner, ts')
+ radArgs (Ident "at":ts) | Just (org, ts') <- position ts =
+ (Ellipse, org, FarthestCorner, ts')
+ radArgs (Ident "circle":Ident "at":ts)
+ | Just (org, ts') <- position ts = (Circle,org,FarthestCorner,ts')
+ radArgs (Ident "circle":ts)
+ | Just (_, Ident "at":ts') <- circleExt ts,
+ Just (org, stops) <- position ts' =
+ (Circle, org, FarthestCorner, stops)
+ | Just (_,ts')<-circleExt ts=(Circle,center,FarthestCorner,ts')
+ | otherwise = (Circle, center, FarthestCorner, ts)
+ radArgs (Ident "ellipse":Ident "at":ts)
+ | Just (org,ts')<-position ts=(Ellipse,org,FarthestCorner,ts')
+ radArgs (Ident "ellipse":ts)
+ | Just (_, Ident "at":ts') <- ellipseExt ts,
+ Just (org, stops) <- position ts' =
+ (Ellipse, org, FarthestCorner, stops)
+ | Just (_,ts')<-ellipseExt ts=(Ellipse,center,FarthestCorner,ts')
+ | otherwise = (Ellipse, center, FarthestCorner, ts)
+ radArgs ts | Just (_, Ident "at":ts') <- ellipseExt ts,
+ Just (org, stops) <- position ts' =
+ (Ellipse, org, FarthestCorner, stops)
+ | Just (_, Ident "ellipse":Ident "at":ts') <- ellipseExt ts,
+ Just (org, stops) <- position ts' =
+ (Ellipse, org, FarthestCorner, stops)
+ | Just (_, Ident "ellipse":ts') <- ellipseExt ts =
+ (Ellipse, center, FarthestCorner, ts')
+ | Just (_, Ident "circle":Ident "at":ts') <- circleExt ts,
+ Just (org, stops) <- position ts' =
+ (Circle, org, FarthestCorner, stops)
+ | Just (_, Ident "circle":ts') <- circleExt ts =
+ (Circle, center, FarthestCorner, ts')
+ | otherwise = (Ellipse, center, FarthestCorner, ts)
+ radShape "circle" = Just Circle
+ radShape "ellipse" = Just Ellipse
+ radShape _ = Nothing
+ radExt (Ident "closest-corner":ts) = Just (ClosestCorner, ts)
+ radExt (Ident "closest-side":ts) = Just (ClosestSide, ts)
+ radExt (Ident "farthest-corner":ts) = Just (FarthestCorner, ts)
+ radExt (Ident "farthest-side":ts) = Just (FarthestSide, ts)
+ radExt _ = Nothing
+ ellipseExt ts | Just ret <- radExt ts = Just ret
+ ellipseExt (Percentage _ x:Percentage _ y:ts) =
+ Just (p' x `Extent` p' y, ts)
+ ellipseExt (Percentage _ x:Dimension _ y "px":ts) =
+ Just (p' x `Extent` f' y, ts)
+ ellipseExt (Dimension _ x "px":Percentage _ y:ts) =
+ Just (f' x `Extent` p' y, ts)
+ ellipseExt (Dimension _ x "px":Dimension _ y "px":ts) =
+ Just (f' x `Extent` p' y, ts)
+ ellipseExt _ = Nothing
+ circleExt (Dimension _ x "px":ts) = Just (f' x `Extent` f' x, ts)
+ circleExt ts = radExt ts
+ -- NOTE: Not implementing colourspaces yet...
+ inner (Function "conic-gradient":Ident "from":Dimension _ x unit:
+ Ident "at":ts)
+ | Just (org, ts') <- position ts, Just s <- lookup unit angularUnits,
+ Just stops@(_:_:_) <- colourStops pp ts' =
+ Just $ Conical (f x*s) org stops
+ inner (Function "conic-gradient":Ident "from":Dimension _ x unit:ts)
+ | Just s <- lookup unit angularUnits,
+ Just stops@(_:_:_) <- colourStops pp ts =
+ Just $ Conical (f x*s) center stops
+ inner (Function "conic-gradient":Ident "at":ts)
+ | Just (org, ts') <- position ts,
+ Just cs@(_:_:_) <- colourStops pp ts' = Just $ Conical 0 org cs
+ inner (Function "conic-gradient":ts)
+ | Just stops@(_:_:_) <- colourStops pp (Comma:ts) =
+ Just $ Conical 0 center stops
+ inner _ = Nothing
+
+ angularUnits = [("deg",pi/180),("grad",pi/200),("rad",1),("turn",2*pi)]
+ center = (Scale 0.5, Scale 0.5)
+ longhand _ self "background-origin" t | val@(_:_) <- parseCSSList box t =
+ Just self { origin = reverse val }
+ longhand _ self "background-position" t | val@(_:_) <- parseCSSList position t,
+ all (null . snd) val = Just self { bgPos = reverse $ map fst val }
+ longhand _ self "background-repeat" t | val@(_:_) <- parseCSSList inner t =
+ Just self { bgRepeat = reverse val }
+ where
+ inner [Ident "initial"] = Just (True, True)
+ inner [Ident "repeat-x"] = Just (True, False)
+ inner [Ident "repeat-y"] = Just (False, True)
+ inner [x] | Just y <- inner' x = Just (y, y)
+ inner [x, y] | Just x' <- inner' x, Just y' <- inner' y = Just (x', y')
+ inner _ = Nothing
+ inner' (Ident "repeat") = Just True
+ inner' (Ident "no-repeat") = Just False
+ inner' _ = Nothing
+ longhand _ self "background-size" t | val@(_:_) <- parseCSSList inner t =
+ Just self { bgSize = reverse val }
+ where -- TODO: Add shorthand support, after background-position.
+ inner [x, y] | Just a <- l x, Just b <- l y = Just $ Size a b
+ inner [Ident "contain"] = Just Contain
+ inner [Ident "cover"] = Just Cover
+ inner [Ident "auto"] = Just $ Size Auto Auto
+ inner [Ident "initial"] = Just $ Size Auto Auto
+ inner _ = Nothing
+ -- NOTE: Leave lowering other units to CatTrap.
+ l (Ident "auto") = Just Auto
+ l (Dimension _ x "px") = Just $ Absolute $ f x
+ l (Percentage _ x) = Just $ Scale $ p x
+ l _ = Nothing
+ longhand _ _ _ _ = Nothing
+
+ -- The multi-layered shorthand is one source of parsing complexity.
+ shorthand self "background" t = catProps $ reverse $ parseCSSList inner t
+ where
+ catProps [] = []
+ catProps (props:pss)
+ | Just [Ident "initial"] <- "background-color" `lookup` catProps pss =
+ map (catProp $ catProps pss) props
+ | otherwise = [] -- Only allow background-color in bottommost layer.
+ catProp _ ret@("background-color", _) = ret
+ catProp bases (key, val)
+ | Just base <- key `lookup` bases = (key, base ++ Comma:val)
+ -- Shouldn't happen, `inner` expands all props at least to "initial"!
+ | otherwise = (key, val)
+ inner toks | ret@(_:_) <- parseUnorderedShorthand self [
+ "background-color", "background-clip", "background-image",
+ "background-origin", "background-position"
+ ] toks = Just ret
+ | otherwise = Nothing
+ shorthand self key val | Just _ <- longhand self self key val = [(key, val)]
+ | otherwise = []
+
+box :: [Token] -> Maybe (Rects -> Rect)
+box [Ident "content-box"] = Just contentBox
+box [Ident "padding-box"] = Just paddingBox
+box [Ident "border-box"] = Just borderBox
+box [Ident "initial"] = Just borderBox -- To aid shorthand implementation.
+box _ = Nothing
+
+position :: [Token] -> Maybe ((Length, Length), [Token])
+position (x:y:ts) = position' x y ts <* position' y x ts <* position' x x (y:ts)
+position [x] = position' x x []
+position _ = Nothing
+position' :: Token -> Token -> [Token] -> Maybe ((Length, Length), [Token])
+position' x y ts = case ((case x of
+ Ident "left" -> Scale 0
+ Ident "center" -> Scale 0.5
+ Ident "right" -> Scale 1
+ Percentage _ a -> p' a
+ Dimension _ a "px" -> f' a
+ _ -> Auto,
+ case y of
+ Ident "top" -> Scale 0
+ Ident "center" -> Scale 0.5
+ Ident "bottom" -> Scale 1
+ Percentage _ a -> p' a
+ Dimension _ a "px" -> f' a
+ _ -> Auto),
+ ts) of
+ ((Auto, _), _) -> Nothing
+ ((_, Auto), _) -> Nothing
+ ret -> Just ret
+
+colourStops :: ColourPallet
+ -> [Token] -> Maybe [(AlphaColour Float, Length)]
+colourStops _ [RightParen] = Just []
+colourStops cs (Comma:toks)
+ | Just (Percentage _ x:toks', c) <- parseColour cs toks,
+ Just ret <- colourStops cs toks' = Just $ (c, Scale $ p x):ret
+ | Just (Dimension _ x "px":toks', c) <- parseColour cs toks,
+ Just ret <- colourStops cs toks' = Just $ (c, Absolute $ f x):ret
+ | Just (toks', c) <- parseColour cs toks,
+ Just ret <- colourStops cs toks' = Just $ (c, Auto):ret
+colourStops cs (Comma:Percentage _ x:toks)
+ | Just (toks', c) <- parseColour cs toks,
+ Just ret <- colourStops cs toks' = Just $ (c, Scale $ p x):ret
+colourStops cs (Comma:Dimension _ x "px":toks)
+ | Just (toks', c) <- parseColour cs toks,
+ Just ret <- colourStops cs toks' = Just $ (c, Absolute $ f x):ret
+colourStops _ _ = Nothing
+
+parseCSSList :: ([Token] -> Maybe a) -> [Token] -> [a]
+parseCSSList cb toks | all isJust ret = catMaybes ret
+ | otherwise = []
+ where ret = map cb $ map concat $ splitList [Comma] $ parseOperands toks
+
+f :: NumericValue -> Float
+f (NVInteger x) = fromInteger x
+f (NVNumber x) = toRealFloat x
+p :: NumericValue -> Float
+p (NVInteger x) = fromInteger x / 100
+-- Do the division while we're in base-10!
+p (NVNumber x) = toRealFloat (x/scientific 1 2)
+p' :: NumericValue -> Length
+p' = Scale . p
+f' :: NumericValue -> Length
+f' = Absolute . f
+
+------
+--- Utils taken from HappStack
+------
+
+-- | Repeadly splits a list by the provided separator and collects the results
+splitList :: Eq a => a -> [a] -> [[a]]
+splitList _ [] = []
+splitList sep list = h:splitList sep t
+ where (h,t)=split (==sep) list
+
+-- | Split is like break, but the matching element is dropped.
+split :: (a -> Bool) -> [a] -> ([a], [a])
+split filt s = (x,y)
+ where
+ (x,y')=break filt s
+ y = if null y' then [] else tail y'
+
+------
+--- Dynamically-computed properties
+------
+
+resolveSize :: (Float, Float) -> (Float, Float) -> Resize -> (Float, Float)
+resolveSize (owidth, oheight) (width, height) Contain
+ | width > owidth, height*sw > oheight, height > width = (width*sh, height*sh)
+ | width > owidth = (width*sw, height*sw)
+ | height > oheight = (width*sh, height*sh)
+ | height > width = (width*sw, height*sw)
+ | otherwise = (width*sh, height*sh)
+ where
+ sh = oheight/height
+ sw = owidth/width
+resolveSize (owidth, oheight) (width, height) Cover
+ | owidth > width, oheight > height*sw = (width*sh, height*sh)
+ | oheight > height, owidth > width*sh = (width*sw, height*sw)
+ | owidth > width = (width*sw, height*sw)
+ | oheight > height = (width*sh, height*sh)
+ | oheight > height*sw = (width*sh, height*sh)
+ | owidth > width*sh = (width*sw, height*sw)
+ | height > width = (width*sw, height*sw)
+ | otherwise = (width*sh, height*sh)
+ where
+ sh = oheight/height
+ sw = owidth/width
+resolveSize _ ret (Size Auto Auto) = ret
+resolveSize _ (width, height) (Size x y) = (x', y')
+ where
+ x' | Absolute ret <- x = ret
+ | Scale s <- x = width*s
+ | Auto <- x = y' * width/height
+ y' | Absolute ret <- y = ret
+ | Scale s <- y = height*s
+ -- NOTE: If Auto,Auto case wasn't handled above this'd be an infinite loop.
+ | Auto <- y = x' * height/width
diff --git a/lib/Graphics/Rendering/Rect/CSS/Border.hs b/lib/Graphics/Rendering/Rect/CSS/Border.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/CSS/Border.hs
@@ -0,0 +1,169 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Graphics.Rendering.Rect.CSS.Border(Border(..), BorderStyle(..),
+ topColour, rightColour, bottomColour, leftColour) where
+
+import Stylist (PropertyParser(..), parseUnorderedShorthand, parseOperands)
+import Data.CSS.Syntax.Tokens (Token(..))
+import Graphics.Rendering.Rect.CSS.Colour (ColourPallet(foreground), parseColour)
+import Data.Colour (AlphaColour)
+import Data.Maybe (fromMaybe, isJust)
+import Data.Text (Text)
+
+data Border = Border {
+ borderPallet :: ColourPallet,
+ topStyle :: BorderStyle,
+ topColour' :: Maybe (AlphaColour Float),
+ rightStyle :: BorderStyle,
+ rightColour' :: Maybe (AlphaColour Float),
+ bottomStyle :: BorderStyle,
+ bottomColour' :: Maybe (AlphaColour Float),
+ leftStyle :: BorderStyle,
+ leftColour' :: Maybe (AlphaColour Float)
+} deriving (Eq, Show, Read)
+
+resolveColour :: Border -> Maybe (AlphaColour Float) -> AlphaColour Float
+resolveColour self = fromMaybe $ foreground $ borderPallet self
+topColour, rightColour, bottomColour, leftColour :: Border -> AlphaColour Float
+topColour self = resolveColour self $ topColour' self
+rightColour self = resolveColour self $ rightColour' self
+bottomColour self = resolveColour self $ bottomColour' self
+leftColour self = resolveColour self $ leftColour' self
+
+data BorderStyle = NoBorder | Solid | Dashed | Dotted | Double
+ | Groove | Ridge | Inset | Outset deriving (Eq, Show, Read, Enum)
+
+style :: Token -> Maybe BorderStyle
+style (Ident "initial") = Just NoBorder
+style (Ident "none") = Just NoBorder
+style (Ident "hidden") = Just NoBorder
+style (Ident "solid") = Just Solid
+style (Ident "dashed") = Just Dashed
+style (Ident "dotted") = Just Dotted
+style (Ident "double") = Just Double
+style (Ident "groove") = Just Groove
+style (Ident "ridge") = Just Ridge
+style (Ident "inset") = Just Inset
+style (Ident "outset") = Just Outset
+style _ = Nothing
+
+instance PropertyParser Border where
+ temp = Border {
+ borderPallet = temp,
+ topStyle = NoBorder,
+ topColour' = Nothing,
+ rightStyle = NoBorder,
+ rightColour' = Nothing,
+ bottomStyle = NoBorder,
+ bottomColour' = Nothing,
+ leftStyle = NoBorder,
+ leftColour' = Nothing
+ }
+ inherit = const temp
+ priority = const []
+
+ longhand _ s "border-top-style" [t] | Just v <- style t = Just s {topStyle=v}
+ longhand _ s "border-right-style" [t] | Just v<-style t=Just s {rightStyle=v}
+ longhand _ s "border-bottom-style" [t]|Just v<-style t=Just s {bottomStyle=v}
+ longhand _ s "border-left-style" [t] | Just v<-style t = Just s {leftStyle=v}
+ longhand _ self@Border { borderPallet = cc } "border-top-color" ts
+ | Just ([], v) <- parseColour cc ts = Just self { topColour' = Just v }
+ longhand _ self@Border { borderPallet = cc } "border-right-color" ts
+ | Just ([], v) <- parseColour cc ts = Just self { rightColour' = Just v }
+ longhand _ self@Border { borderPallet = cc } "border-bottom-color" ts
+ | Just ([], v) <- parseColour cc ts = Just self { bottomColour' = Just v }
+ longhand _ self@Border { borderPallet = cc } "border-left-color" ts
+ | Just ([], v) <- parseColour cc ts = Just self { leftColour' = Just v }
+
+ -- Should be handled by caller, but for the sake of shorthands...
+ longhand _ self "border-top-width" [Dimension _ _ "px"] = Just self
+ longhand _ self "border-right-width" [Dimension _ _ "px"] = Just self
+ longhand _ self "border-bottom-width" [Dimension _ _ "px"] = Just self
+ longhand _ self "border-left-width" [Dimension _ _ "px"] = Just self
+ longhand _ _ _ _ = Nothing
+
+ shorthand self "border-width" toks
+ | length x > 0 && length x <= 4, (top:right:bottom:left:_) <- cycle x,
+ all (validProp self "border-top-width") x =
+ [("border-top-width", top), ("border-right-width", right),
+ ("border-bottom-width", bottom), ("border-left-width", left)]
+ where x = parseOperands toks
+ -- Define other border shorthands here to properly handle border-widths
+ shorthand self "border" toks = parseUnorderedShorthand self [
+ "border-color", "border-style", "border-width"] toks
+ shorthand self "border-top" toks = parseUnorderedShorthand self [
+ "border-top-color", "border-top-style", "border-top-width"] toks
+ shorthand self "border-right" toks = parseUnorderedShorthand self [
+ "border-right-color", "border-right-style", "border-right-width"] toks
+ shorthand self "border-bottom" toks = parseUnorderedShorthand self [
+ "border-bottom-color", "border-bottom-style", "border-bottom-width"] toks
+ shorthand self "border-left" toks = parseUnorderedShorthand self [
+ "border-left-color", "border-left-style", "border-left-width"] toks
+ shorthand self "border-inline" toks = parseUnorderedShorthand self [
+ "border-inline-color", "border-inline-style", "border-inline-width"] toks
+ shorthand self "border-inline-start" toks = parseUnorderedShorthand self [
+ "border-inline-start-color", "border-inline-start-style",
+ "border-inline-start-width"] toks
+ shorthand self "border-inline-end" toks = parseUnorderedShorthand self [
+ "border-inline-end-color", "border-inline-end-style",
+ "border-inline-end-width"] toks
+ shorthand self "border-block" toks = parseUnorderedShorthand self [
+ "border-block-color", "border-block-style", "border-block-width"] toks
+ shorthand self "border-block-start" toks = parseUnorderedShorthand self [
+ "border-block-start-color", "border-block-start-style",
+ "border-block-start-width"] toks
+ shorthand self "border-block-end" toks = parseUnorderedShorthand self [
+ "border-block-end-color", "border-block-end-style",
+ "border-block-end-width"] toks
+ shorthand self "border-color" toks
+ | length x > 0 && length x <= 4, (top:right:bottom:left:_) <- cycle x,
+ all (validProp self "border-top-color") x =
+ [("border-top-color", top), ("border-right-color", right),
+ ("border-bottom-color", bottom), ("border-left-color", left)]
+ where x = parseOperands toks
+ shorthand self "border-style" toks
+ | length x > 0 && length x <= 4, (top:right:bottom:left:_) <- cycle x,
+ all (validProp self "border-top-style") x =
+ [("border-top-style", top), ("border-right-style", right),
+ ("border-bottom-style", bottom), ("border-left-style", left)]
+ where x = parseOperands toks
+ shorthand self "border-width" toks
+ | length x > 0 && length x <= 4, (top:right:bottom:left:_) <- cycle x,
+ all (validProp self "border-top-width") x =
+ [("border-top-width", top), ("border-right-width", right),
+ ("border-bottom-width", bottom), ("border-left-width", left)]
+ where x = parseOperands toks
+ shorthand self "border-inline-color" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-inline-start-color") x =
+ [("border-inline-start-color", s), ("border-inline-end-color", e)]
+ where x = parseOperands toks
+ shorthand self "border-inline-style" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-inline-start-style") x =
+ [("border-inline-start-style", s), ("border-inline-end-style", e)]
+ where x = parseOperands toks
+ shorthand self "border-inline-width" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-inline-start-width") x =
+ [("border-inline-start-width", s), ("border-inline-end-style", e)]
+ where x = parseOperands toks
+ shorthand self "border-block-color" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-block-start-color") x =
+ [("border-block-start-color", s), ("border-block-end-color", e)]
+ where x = parseOperands toks
+ shorthand self "border-block-style" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-block-start-style") x =
+ [("border-block-start-style", s), ("border-block-end-style", e)]
+ where x = parseOperands toks
+ shorthand self "border-block-width" toks
+ | length x > 0 && length x <= 2, (s:e:_) <- cycle x,
+ all (validProp self "border-block-start-width") x =
+ [("border-block-start-width", s), ("border-block-end-width", e)]
+ where x = parseOperands toks
+ shorthand self k v | Just _ <- longhand self self k v = [(k, v)]
+ | otherwise = []
+
+validProp :: PropertyParser a => a -> Text -> [Token] -> Bool
+validProp self key value = isJust $ longhand self self key value
diff --git a/lib/Graphics/Rendering/Rect/CSS/Colour.hs b/lib/Graphics/Rendering/Rect/CSS/Colour.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/CSS/Colour.hs
@@ -0,0 +1,310 @@
+{-# LANGUAGE OverloadedStrings, PatternSynonyms, ViewPatterns #-}
+module Graphics.Rendering.Rect.CSS.Colour(ColourPallet(..), parseColour) where
+
+import Data.Colour (Colour, AlphaColour, withOpacity, opaque, transparent)
+import Data.Colour.SRGB (sRGB, sRGB24)
+import Data.Colour.Names
+import Data.Colour.RGBSpace.HSL (hsl)
+import Data.Colour.RGBSpace (uncurryRGB)
+import Data.Colour.SRGB.Linear (rgb)
+
+import Data.CSS.Syntax.Tokens (Token(..), NumericValue(..))
+import Data.Scientific (toRealFloat)
+import qualified Data.Text as Txt
+
+import Data.Word (Word8)
+import Data.Char (isHexDigit, toLower)
+import Data.List (elemIndex)
+import Debug.Trace (trace) -- For warning messages.
+
+import Stylist (PropertyParser(..))
+
+hsl' :: RealFrac a => a -> a -> a -> Colour a
+hsl' hue s l = uncurryRGB rgb $ hsl hue s l
+
+data ColourPallet = ColourPallet {
+ foreground :: AlphaColour Float,
+ accent :: AlphaColour Float
+} deriving (Read, Show, Eq)
+
+instance PropertyParser ColourPallet where
+ temp = ColourPallet { foreground = opaque black, accent = opaque blue }
+ inherit = id
+ priority _ = ["color", "accent"]
+
+ longhand _ self "color" [Ident "initial"]=Just self {foreground=opaque black}
+ longhand _ self "color" toks | Just ([], val) <- parseColour self toks =
+ Just self { foreground = val }
+ longhand _ self "accent-color" [Ident kw]
+ | kw `elem` ["initial", "auto"] = Just self {accent = opaque blue}
+ longhand _ self "accent-color" t | Just ([], val) <- parseColour self t =
+ Just self { accent = val }
+ longhand _ _ _ _ = Nothing
+ shorthand self key val | Just _ <- longhand self self key val = [(key, val)]
+ | otherwise = []
+
+parseColour :: ColourPallet -> [Token] -> Maybe ([Token], AlphaColour Float)
+parseColour _ (Function "rgb":Percentage _ r:Comma:
+ Percentage _ g:Comma:Percentage _ b:RightParen:toks) =
+ Just (toks, opaque $ sRGB (pc r) (pc g) (pc b))
+parseColour _ (Function "rgba":Percentage _ r:Comma:
+ Percentage _ g:Comma:Percentage _ b:Comma:a':RightParen:toks)
+ | a' /= Ident "none", Just a <- f' a' =
+ Just (toks, sRGB (pc r) (pc g) (pc b) `withOpacity` a)
+parseColour _ (Function "rgb":Number _ (NVInteger r):Comma:
+ Number _ (NVInteger g):Comma:Number _ (NVInteger b):RightParen:toks) =
+ Just (toks, opaque $ sRGB24 (w r) (w g) (w b))
+parseColour _ (Function "rgba":Number _ (NVInteger r):Comma:
+ Number _ (NVInteger g):Comma:Number _ (NVInteger b):Comma:
+ a':RightParen:toks) | a' /= Ident "none", Just a <- f' a' =
+ Just (toks, sRGB24 (w r) (w g) (w b) `withOpacity` a)
+
+parseColour _ (Function "rgb":r':g':b':RightParen:toks)
+ | Just r <- w' r', Just g <- w' g', Just b <- w' b' =
+ Just (toks, opaque $ sRGB24 r g b)
+parseColour _ (Function "rgb":r':g':b':Delim '/':a':RightParen:toks)
+ | Just r <- w' r', Just g <- w' g', Just b <- w' b', Just a <- f' a' =
+ Just (toks, sRGB24 r g b `withOpacity` a)
+parseColour _ (Hash _ v@(r0 :. r1 :. g0 :. g1 :. b0 :. b1 :. ""):toks)
+ | Txt.all isHexDigit v = Just (toks, opaque $ sRGBhex r0 r1 g0 g1 b0 b1)
+parseColour _ (Hash _ v@(r0 :. r1 :. g0 :. g1 :. b0 :. b1 :. a0 :. a1 :. ""):toks)
+ | Txt.all isHexDigit v =
+ Just (toks, sRGBhex r0 r1 g0 g1 b0 b1 `withOpacity` h' a0 a1)
+parseColour _ (Hash _ v@(r:.g:.b:.""):toks) | Txt.all isHexDigit v =
+ Just (toks, opaque $ sRGBhex r r g g b b)
+parseColour _ (Hash _ v@(r:.g:.b:.a:.""):toks) | Txt.all isHexDigit v =
+ Just (toks, sRGBhex r r g g b b `withOpacity` h' a a)
+
+parseColour _ (Ident x:toks) | Just x' <- inner $ Txt.toLower x =
+ Just (toks, opaque x')
+ where
+ -- NOTE: Some of these colour names are inconsistant or even offensive.
+ -- There are historical reasons for this labelling.
+ -- https://www.youtube.com/watch?v=HmStJQzclHc
+ inner "aliceblue" = Just aliceblue
+ inner "antiquewhite" = Just antiquewhite
+ inner "aqua" = Just aqua
+ inner "aquamarine" = Just aquamarine
+ inner "azure" = Just azure
+ inner "beige" = Just beige
+ inner "bisque" = Just bisque
+ inner "black" = Just black
+ inner "blanchedalmond" = Just blanchedalmond
+ inner "blue" = Just blue
+ inner "blueviolet" = Just blueviolet
+ inner "brown" = Just brown
+ inner "burlywood" = Just burlywood
+ inner "cadetblue" = Just cadetblue
+ inner "chartreuse" = Just chartreuse
+ inner "chocolate" = Just chocolate
+ inner "coral" = Just coral
+ inner "cornflowerblue" = Just cornflowerblue
+ inner "cornsilk" = Just cornsilk
+ inner "crimson" = Just crimson
+ inner "cyan" = Just cyan
+ inner "darkblue" = Just darkblue
+ inner "darkcyan" = Just darkcyan
+ inner "darkgoldenrod" = Just darkgoldenrod
+ inner "darkgray" = Just darkgray
+ inner "darkgrey" = Just darkgrey
+ inner "darkgreen" = Just darkgreen
+ inner "darkkhaki" = Just darkkhaki
+ inner "darkmagenta" = Just darkmagenta
+ inner "darkolivegreen" = Just darkolivegreen
+ inner "darkorange" = Just darkorange
+ inner "darkorchid" = Just darkorchid
+ inner "darkred" = Just darkred
+ inner "darksalmon" = Just darksalmon
+ inner "darkseagreen" = Just darkseagreen
+ inner "darkslateblue" = Just darkslateblue
+ inner "darkslategray" = Just darkslategray
+ inner "darkslategrey" = Just darkslategrey
+ inner "darkturquoise" = Just darkturquoise
+ inner "darkviolet" = Just darkviolet
+ inner "deeppink" = Just deeppink
+ inner "deepskyblue" = Just deepskyblue
+ inner "dimgray" = Just dimgray
+ inner "dimgrey" = Just dimgrey
+ inner "dodgerblue" = Just dodgerblue
+ inner "firebrick" = Just firebrick
+ inner "floralwhite" = Just floralwhite
+ inner "forestgreen" = Just forestgreen
+ inner "fuchsia" = Just fuchsia
+ inner "gainsboro" = Just gainsboro
+ inner "ghostwhite" = Just ghostwhite
+ inner "gold" = Just gold
+ inner "goldenrod" = Just goldenrod
+ inner "gray" = Just gray
+ inner "grey" = Just grey
+ inner "green" = Just green
+ inner "greenyellow" = Just greenyellow
+ inner "honeydew" = Just honeydew
+ inner "hotpink" = Just hotpink
+ inner "indianred" = Just indianred
+ inner "indigo" = Just indigo
+ inner "ivory" = Just ivory
+ inner "khaki" = Just khaki
+ inner "lavender" = Just lavender
+ inner "lavenderblush" = Just lavenderblush
+ inner "lawngreen" = Just lawngreen
+ inner "lemonchiffon" = Just lemonchiffon
+ inner "lightblue" = Just lightblue
+ inner "lightcoral" = Just lightcoral
+ inner "lightcyan" = Just lightcyan
+ inner "lightgoldenrodyellow" = Just lightgoldenrodyellow
+ inner "lightgray" = Just lightgray
+ inner "lightgrey" = Just lightgrey
+ inner "lightgreen" = Just lightgreen
+ inner "lightpink" = Just lightpink
+ inner "lightsalmon" = Just lightsalmon
+ inner "lightseagreen" = Just lightseagreen
+ inner "lightskyblue" = Just lightskyblue
+ inner "lightslategray" = Just lightslategray
+ inner "lightslategrey" = Just lightslategrey
+ inner "lightsteelblue" = Just lightsteelblue
+ inner "lightyellow" = Just lightyellow
+ inner "lime" = Just lime
+ inner "limegreen" = Just limegreen
+ inner "linen" = Just linen
+ inner "magenta" = Just magenta
+ inner "maroon" = Just maroon
+ inner "mediumaquamarine" = Just mediumaquamarine
+ inner "mediumblue" = Just mediumblue
+ inner "mediumorchid" = Just mediumorchid
+ inner "mediumpurple" = Just mediumpurple
+ inner "mediumseagreen" = Just mediumseagreen
+ inner "mediumslateblue" = Just mediumslateblue
+ inner "mediumspringgreen" = Just mediumspringgreen
+ inner "mediumturquoise" = Just mediumturquoise
+ inner "mediumvioletred" = Just mediumvioletred
+ inner "midnightblue" = Just midnightblue
+ inner "mintcream" = Just mintcream
+ inner "mistyrose" = Just mistyrose
+ inner "moccasin" = Just moccasin
+ inner "navajowhite" = Just navajowhite
+ inner "navy" = Just navy
+ inner "oldlace" = Just oldlace
+ inner "olive" = Just olive
+ inner "olivedrab" = Just olivedrab
+ inner "orange" = Just orange
+ inner "orangered" = Just orangered
+ inner "orchid" = Just orchid
+ inner "palegoldenrod" = Just palegoldenrod
+ inner "palegreen" = Just palegreen
+ inner "paleturquoise" = Just paleturquoise
+ inner "palevioletred" = Just palevioletred
+ inner "papayawhip" = Just papayawhip
+ inner "peachpuff" = Just peachpuff
+ inner "peru" = Just peru
+ inner "pink" = Just pink
+ inner "plum" = Just plum
+ inner "powderblue" = Just powderblue
+ inner "purple" = Just purple
+ -- Named after CSS pioneer Eric Meyer's late daughter
+ inner "rebeccapurple" = Just $ sRGB 102 51 153
+ inner "red" = Just red
+ inner "rosybrown" = Just rosybrown
+ inner "royalblue" = Just royalblue
+ inner "saddlebrown" = Just saddlebrown
+ inner "salmon" = Just salmon
+ inner "sandybrown" = Just sandybrown
+ inner "seagreen" = Just seagreen
+ inner "seashell" = Just seashell
+ inner "sienna" = Just sienna
+ inner "silver" = Just silver
+ inner "skyblue" = Just skyblue
+ inner "slateblue" = Just slateblue
+ inner "slategray" = Just slategray
+ inner "slategrey" = Just slategrey
+ inner "snow" = Just snow
+ inner "springgreen" = Just springgreen
+ inner "steelblue" = Just steelblue
+ inner "tan" = Just Data.Colour.Names.tan
+ inner "teal" = Just teal
+ inner "thistle" = Just thistle
+ inner "tomato" = Just tomato
+ inner "turquoise" = Just turquoise
+ inner "violet" = Just violet
+ inner "wheat" = Just wheat
+ inner "white" = Just white
+ inner "whitesmoke" = Just whitesmoke
+ inner "yellow" = Just yellow
+ inner "yellowgreen" = Just yellowgreen
+ inner _ = Nothing
+parseColour _ (Ident x:toks) | Txt.toLower x == "transparent" =
+ Just (toks, transparent)
+-- FIXME: Add infrastructure to prioritize resolving `color`
+parseColour self@ColourPallet { foreground = colour} (Ident x:toks)
+ | Txt.toLower x `elem` ["currentcolor", "initial"] = Just (toks, colour)
+ | Txt.toLower x == "accentcolor" = Just (toks, accent self)
+
+parseColour _ (Function "hsl":hue':Comma:Percentage _ s:Comma:Percentage _ l:
+ RightParen:toks)
+ | Just hue <- d hue' = Just (toks, opaque $ hsl' hue (pc s) (pc l))
+parseColour _ (Function "hsl":hue':Comma:Percentage _ s:Comma:Percentage _ l:
+ Comma:a':RightParen:toks) | Just hue <- d hue', Just a <- f' a' =
+ Just (toks, hsl' hue (pc s) (pc l) `withOpacity` a)
+parseColour _ (Function "hsla":hue':Comma:Percentage _ s:Comma:Percentage _ l:
+ Comma:a':RightParen:toks) | Just hue <- d hue', Just a <- f' a' =
+ Just (toks, hsl' hue (pc s) (pc l) `withOpacity` a)
+parseColour _ (Function "hsl":hue':s':l':RightParen:toks)
+ | Just hue <- d' hue', Just s <- pc' s', Just l <- pc' l' =
+ Just (toks, opaque $ hsl' hue s l)
+parseColour _ (Function "hsl":hue':s':l':Delim '/':a':RightParen:toks)
+ | Just hue <- d' hue', Just s <- pc' s', Just l <- pc' l', Just a <- f' a' =
+ Just (toks, hsl' hue s l `withOpacity` a)
+
+parseColour _ _ = Nothing
+
+sRGBhex :: Char -> Char -> Char -> Char -> Char -> Char -> Colour Float
+sRGBhex r0 r1 g0 g1 b0 b1 = sRGB24 (h r0 r1) (h g0 g1) (h b0 b1)
+
+h :: Char -> Char -> Word8
+h a b
+ | Just a' <- toLower a `elemIndex` digits,
+ Just b' <- toLower b `elemIndex` digits = toEnum a'*16 + toEnum b'
+ | otherwise = trace (a:b:" Invalid hexcode!") 0 -- Should already be checked!
+ where
+ digits = "0123456789abcdef"
+h' :: Char -> Char -> Float
+h' a b = fromIntegral (h a b) / 255
+
+pc :: NumericValue -> Float
+pc x = f x / 100
+pc' :: Token -> Maybe Float
+pc' (Ident "none") = Just 0
+pc' (Percentage _ x) = Just $ pc x
+pc' _ = Nothing
+
+f :: NumericValue -> Float
+f (NVInteger x) = fromIntegral x
+f (NVNumber x) = toRealFloat x
+f' :: Token -> Maybe Float
+f' (Ident "none") = Just 0
+f' (Percentage _ x) = Just $ pc x
+f' (Number _ x) = Just $ f x
+f' _ = Nothing
+
+w :: Integer -> Word8
+w = fromInteger
+w' :: Token -> Maybe Word8
+w' (Ident "none") = Just 0
+w' (Number _ (NVInteger x)) | x >= 0 && x <= 255 = Just $ fromIntegral $ w x
+w' (Percentage _ x) = Just $ toEnum $ fromEnum (pc x * 255)
+w' _ = Nothing
+
+d', d :: Token -> Maybe Float
+d (Dimension _ x "deg") = Just $ f x
+d (Dimension _ x "grad") = Just $ f x / 400 * 360
+d (Dimension _ x "rad") = Just $ f x / pi * 180
+d (Dimension _ x "turn") = Just $ f x * 360
+d (Number _ x) = Just $ f x
+d _ = Nothing
+d' (Ident "none") = Just 0
+d' x = d x
+
+-- Copied from css-syntax.
+pattern (:.) :: Char -> Txt.Text -> Txt.Text
+pattern x :. xs <- (Txt.uncons -> Just (x, xs))
+
+infixr 5 :.
diff --git a/lib/Graphics/Rendering/Rect/Image.hs b/lib/Graphics/Rendering/Rect/Image.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/Image.hs
@@ -0,0 +1,100 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Graphics.Rendering.Rect.Image(
+ Atlas, buildAtlas, Texture(..), atlasLookup, textureSetRepeat) where
+
+import qualified Data.HashMap.Lazy as HM
+import Data.Text (Text)
+import Codec.Picture (DynamicImage(..), Image(..), PixelF, pixelMap)
+import Codec.Picture.Types (promoteImage, dynamicMap, convertImage)
+
+import Control.Monad.IO.Class (MonadIO(..))
+import Control.Monad (forM)
+import Data.Maybe (fromMaybe)
+
+import Graphics.GL.Core32
+import Graphics.GL.Types
+import Graphics.GL.Ext.EXT.Cmyka
+import Graphics.GL.Ext.SGIX.Ycrcb
+import Graphics.GL.Compatibility32
+
+import Data.Vector.Storable (unsafeWith, unsafeCast, Vector)
+import Foreign.Ptr (castPtr)
+import Foreign.Marshal.Array (allocaArray, peekArray)
+
+data Atlas = Atlas { unAtlas :: HM.HashMap Text Texture }
+
+buildAtlas :: MonadIO m => (Text -> IO DynamicImage) -> [Text] -> m Atlas
+buildAtlas _ [] = return $ Atlas HM.empty
+buildAtlas cb srcs = do
+ -- TODO Merge textures into an actual atlas.
+ let len = length srcs
+ textures <- liftIO $ allocaArray (toEnum len) $ \ptr -> do
+ glGenTextures (toEnum len) ptr
+ peekArray len ptr
+ imgs <- liftIO $ forM srcs cb
+
+ sizes <- forM (zip textures imgs) $ \(texture, dyn) -> do
+ -- NOTE: `unsafe` crashes with a divide-by-zero given a `Vector ()`
+ let dyn' = convertDyn dyn
+ let img = dynamicMap (unsafeCast . imageData) dyn' :: Vector Word
+ let (format, word) = glFormat dyn'
+ liftIO $ glBindTexture GL_TEXTURE_2D texture
+ liftIO $ unsafeWith img $ glTexImage2D GL_TEXTURE_2D 0 GL_RGBA
+ (toEnum $ dynamicMap imageWidth dyn')
+ (toEnum $ dynamicMap imageHeight dyn')
+ 0 format word . castPtr
+ liftIO $ glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MIN_FILTER GL_LINEAR
+ liftIO $ glTexParameteri GL_TEXTURE_2D GL_TEXTURE_MAG_FILTER GL_LINEAR
+
+ return (toEnum $ dynamicMap imageWidth dyn',
+ toEnum $ dynamicMap imageHeight dyn')
+
+ let textures' = map (uncurry Texture) $ zip textures sizes
+ return $ Atlas $ HM.fromList $ zip srcs textures'
+
+data Texture = Texture { unTexture :: GLuint, texSize :: (Float, Float) }
+nilTexture :: Texture
+nilTexture = Texture 0 (0, 0)
+atlasLookup :: Text -> Atlas -> Texture
+atlasLookup key = fromMaybe nilTexture . HM.lookup key . unAtlas
+textureSetRepeat :: MonadIO m => Texture -> (Bool, Bool) -> m ()
+textureSetRepeat tex (repeatX, repeatY) = do
+ liftIO $ glBindTexture GL_TEXTURE_2D $ unTexture tex
+ liftIO $ glTexParameteri GL_TEXTURE_2D GL_TEXTURE_WRAP_S $
+ if repeatX then GL_REPEAT else GL_CLAMP_TO_BORDER
+ liftIO $ glTexParameteri GL_TEXTURE_2D GL_TEXTURE_WRAP_T $
+ if repeatY then GL_REPEAT else GL_CLAMP_TO_BORDER
+
+-- Convert pixels to some flavour of RGBA
+convertDyn :: DynamicImage -> DynamicImage
+convertDyn (ImageY8 img) = ImageRGBA8 $ promoteImage img
+convertDyn (ImageY16 img) = ImageRGBA16 $ promoteImage img
+convertDyn (ImageY32 img) =
+ ImageRGBF $ promoteImage (pixelMap fromIntegral img :: Image PixelF)
+convertDyn (ImageYF img) = ImageRGBF $ promoteImage img
+convertDyn (ImageYA8 img) = ImageRGBA8 $ promoteImage img
+convertDyn (ImageYA16 img) = ImageRGBA16 $ promoteImage img
+convertDyn (ImageRGB8 img) = ImageRGB8 img
+convertDyn (ImageRGB16 img) = ImageRGB16 img
+convertDyn (ImageRGBF img) = ImageRGBF img
+convertDyn (ImageRGBA8 img) = ImageRGBA8 img
+convertDyn (ImageRGBA16 img) = ImageRGBA16 img
+convertDyn (ImageYCbCr8 img) = ImageRGB8 $ convertImage img
+convertDyn (ImageCMYK8 img) = ImageRGB8 $ convertImage img
+convertDyn (ImageCMYK16 img) = ImageRGB16 $ convertImage img
+
+glFormat :: DynamicImage -> (GLenum, GLenum)
+glFormat (ImageY8 _) = (GL_LUMINANCE, GL_UNSIGNED_BYTE)
+glFormat (ImageY16 _) = (GL_LUMINANCE, GL_UNSIGNED_SHORT)
+glFormat (ImageY32 _) = (GL_LUMINANCE, GL_UNSIGNED_INT)
+glFormat (ImageYF _) = (GL_LUMINANCE, GL_FLOAT)
+glFormat (ImageYA8 _) = (GL_LUMINANCE_ALPHA, GL_BYTE)
+glFormat (ImageYA16 _) = (GL_LUMINANCE_ALPHA, GL_UNSIGNED_SHORT)
+glFormat (ImageRGB8 _) = (GL_RGB, GL_UNSIGNED_BYTE)
+glFormat (ImageRGB16 _) = (GL_RGB, GL_UNSIGNED_SHORT)
+glFormat (ImageRGBF _) = (GL_RGB, GL_FLOAT)
+glFormat (ImageRGBA8 _) = (GL_RGBA, GL_UNSIGNED_BYTE)
+glFormat (ImageRGBA16 _) = (GL_RGBA, GL_UNSIGNED_BYTE)
+glFormat (ImageYCbCr8 _) = (GL_YCRCB_444_SGIX, GL_UNSIGNED_BYTE)
+glFormat (ImageCMYK8 _) = (GL_CMYK_EXT, GL_UNSIGNED_BYTE)
+glFormat (ImageCMYK16 _) = (GL_CMYK_EXT, GL_UNSIGNED_SHORT)
diff --git a/lib/Graphics/Rendering/Rect/Types.hs b/lib/Graphics/Rendering/Rect/Types.hs
new file mode 100644
--- /dev/null
+++ b/lib/Graphics/Rendering/Rect/Types.hs
@@ -0,0 +1,142 @@
+{-# LANGUAGE RecordWildCards #-}
+-- So getters can implement typeclasses
+{-# LANGUAGE TypeSynonymInstances, FlexibleInstances #-}
+module Graphics.Rendering.Rect.Types(Rect(..), size, Rects(..), BoxSelector,
+ Uniform, u, us, c, cs, renderRectWith, liftGL) where
+
+import Linear (M44, V2(..), V4(..))
+import qualified Data.ByteString.Char8 as B8
+import Data.ByteString (ByteString)
+import qualified Data.Vector.Unboxed as UV
+
+import Typograffiti.GL
+import Graphics.GL.Core32
+import Graphics.GL.Types
+import Foreign.Marshal.Array (withArray, withArrayLen)
+import Foreign.Ptr (castPtr)
+
+import Control.Monad.IO.Class (MonadIO(..))
+import Control.Monad (forM)
+import System.Exit (die)
+
+import Data.Colour (AlphaColour, over, alphaChannel)
+import Data.Colour.SRGB (RGB(..), toSRGB)
+import Data.Colour.Names (black)
+import Graphics.Rendering.Rect.Image (Texture(..))
+
+data Rect = Rect {
+ left :: Float, top :: Float,
+ right :: Float, bottom :: Float
+} deriving (Read, Show, Eq, Ord)
+rect2geom :: Rect -> UV.Vector (V2 Float)
+rect2geom Rect{..} = UV.fromList
+ [V2 left top, V2 right top, V2 left bottom, V2 right bottom]
+size :: Rect -> (Float, Float)
+size Rect {..} = (right - left, bottom - top)
+
+data Rects = Rects {
+ contentBox :: Rect,
+ paddingBox :: Rect,
+ borderBox :: Rect,
+ marginBox :: Rect
+} deriving (Read, Show, Eq, Ord)
+rect :: Float -> Rect
+rect x = Rect x x x x
+
+type BoxSelector = Rects -> Rect
+instance Eq BoxSelector where
+ a == b = a rects == b rects
+ where rects = Rects (rect 0) (rect 1) (rect 2) (rect 3)
+instance Show BoxSelector where
+ show a | a rects == rect 0 = "contentBox"
+ | a rects == rect 1 = "paddingBox"
+ | a rects == rect 2 = "borderBox"
+ | a rects == rect 3 = "marginBox"
+ | otherwise = "?"
+ where rects = Rects (rect 0) (rect 1) (rect 2) (rect 3)
+instance Read BoxSelector where
+ readsPrec _ ('c':'o':'n':'t':'e':'n':'t':'B':'o':'x':t) = [(contentBox, t)]
+ readsPrec _ ('p':'a':'d':'d':'i':'n':'g':'B':'o':'x':t) = [(paddingBox, t)]
+ readsPrec _ ('b':'o':'r':'d':'e':'r':'B':'o':'x':t) = [(borderBox, t)]
+ readsPrec _ ('m':'a':'r':'g':'i':'n':'B':'o':'x':t) = [(marginBox, t)]
+ readsPrec _ _ = []
+
+vertexShader :: ByteString
+vertexShader = B8.pack $ unlines [
+ "#version 330 core",
+ "uniform mat4 transform;",
+ "uniform vec2 origin;",
+ "in vec2 pos;",
+ "out vec2 coord;",
+ "void main() {",
+ " gl_Position = vec4(pos, 0, 1) * transform;",
+ " coord = pos - origin;",
+ "}"
+ ]
+
+type Uniform m = GLuint -> GLint -> m ()
+u :: (MonadIO m, UniformValue a) => a -> Uniform m
+u val prog slot = liftIO $ updateUniform prog slot val
+us :: MonadIO m => [Float] -> Uniform m
+us vals prog slot = do
+ liftIO $ withArrayLen vals $ \len -> glUniform1fv slot (toEnum len)
+ clearUniformUpdateError prog slot vals
+
+c :: MonadIO m => AlphaColour Float -> Uniform m
+c rgba = u $ c' rgba
+c' :: AlphaColour Float -> V4 Float
+c' rgba = V4 r g b a
+ where
+ a = alphaChannel rgba
+ -- Workaround for missing APIs in "colour" hackage.
+ RGB r g b = toSRGB $ over rgba black
+cs :: MonadIO m => Int -> [AlphaColour Float] -> Uniform m
+cs mlen rgba prog slot = do
+ let val = map c' $ take mlen rgba
+ liftIO $ withArrayLen val $ \len -> glUniform4fv slot (toEnum len) . castPtr
+ clearUniformUpdateError prog slot val
+
+renderRectWith :: (MonadIO m, MonadIO n) => ByteString -> [String] ->
+ n ([Texture] -> [Uniform m] -> (a -> Rect) -> (a -> Rect) -> a
+ -> M44 Float -> m ())
+renderRectWith fragmentShader uniformNames = do
+ vs <- liftGL $ compileOGLShader vertexShader GL_VERTEX_SHADER
+ fs <- liftGL $ compileOGLShader fragmentShader GL_FRAGMENT_SHADER
+ prog <- liftGL $ compileOGLProgram [("pos", 0)] [vs, fs]
+ uniformIDs <- forM uniformNames $ getUniformLocation prog
+ matID <- getUniformLocation prog "transform"
+ originID <- getUniformLocation prog "origin"
+ szID <- getUniformLocation prog "boxSize"
+ glUseProgram prog
+ glEnable GL_BLEND
+ glBlendFunc GL_SRC_ALPHA GL_ONE_MINUS_SRC_ALPHA
+ return $ \textures uniforms clip' origin' rects mat -> do
+ vao <- liftIO $ newBoundVAO
+ pbuf <- newBuffer
+ bufferGeometry 0 pbuf $ rect2geom $ clip' rects
+
+ glUseProgram prog
+ liftIO $ updateUniform prog matID $ mflip mat
+ let r = origin' rects
+ liftIO $ updateUniform prog originID $ V2 (left r) (top r)
+ liftIO $ updateUniform prog szID $ V2 (right r - left r) (bottom r - top r)
+ _ <- forM (zip uniformIDs uniforms) $ \(slot, cb) -> cb prog slot
+
+ withBoundTextures (map unTexture textures) $ do
+ glBindVertexArray vao
+ drawVAO prog vao GL_TRIANGLE_STRIP 4
+ glBindVertexArray 0
+
+ liftIO $ withArray [pbuf] $ glDeleteBuffers 1
+ liftIO $ withArray [vao] $ glDeleteVertexArrays 1
+
+liftGL :: MonadIO m => IO (Either String a) -> m a
+liftGL n = do
+ ret <- liftIO n
+ case ret of
+ Left err -> liftIO $ die err
+ Right x -> return x
+
+mflip :: V4 (V4 a) -> V4 (V4 a)
+mflip (V4 (V4 a b cc d) (V4 e f g h) (V4 i j k l) (V4 m n o p)) =
+ V4 (V4 a e i m) (V4 b f j n) (V4 cc g k o) (V4 d h l p)
diff --git a/test/MyLibTest.hs b/test/MyLibTest.hs
new file mode 100644
--- /dev/null
+++ b/test/MyLibTest.hs
@@ -0,0 +1,4 @@
+module Main (main) where
+
+main :: IO ()
+main = putStrLn "Test suite not yet implemented."