gloss-rendering 1.13.1.2 → 1.13.2.1

raw patch · 4 files changed

+79/−6 lines, 4 files

Files

• Graphics/Gloss/Internals/Data/Picture.hs +1/−1
• Graphics/Gloss/Internals/Rendering/Picture.hs +2/−2
• Graphics/Gloss/Internals/Rendering/Polygon.hs +72/−0
• gloss-rendering.cabal +4/−3

@@ -63,7 +63,7 @@         -- | A blank picture, with nothing in it.         = Blank -        -- | A convex polygon filled with a solid color.+        -- | A polygon filled with a solid color.         | Polygon       Path          -- | A line along an arbitrary path.

@@ -7,6 +7,7 @@ import Graphics.Gloss.Internals.Rendering.State import Graphics.Gloss.Internals.Rendering.Common import Graphics.Gloss.Internals.Rendering.Circle+import Graphics.Gloss.Internals.Rendering.Polygon import Graphics.Gloss.Internals.Rendering.Bitmap import Graphics.Gloss.Internals.Data.Picture import Graphics.Gloss.Internals.Data.Color@@ -65,8 +66,7 @@                 $ vertexPFs path           | otherwise-         -> GL.renderPrimitive GL.Polygon-                $ vertexPFs path+         -> renderComplexPolygon path          -- circle         Circle radius

@@ -0,0 +1,72 @@+{-# OPTIONS_HADDOCK hide #-}++module Graphics.Gloss.Internals.Rendering.Polygon(renderComplexPolygon) where+import Graphics.Gloss.Internals.Rendering.Common+import Graphics.Rendering.OpenGL.GLU.Tessellation+import qualified Graphics.Rendering.OpenGL.GL           as GL++combiner :: a -> b -> ()+combiner _ _ = ()+++-- written this way to measurably improve performance+zipLoop :: [a] -> [(a,a)]+zipLoop [] = []+zipLoop (x:xs) = go x xs where+  go y [] = [(y,x)]+  go y (z:rs) = (y,z) : go z rs++zipWithLoop :: (a->a->b) -> [a] -> [b]+zipWithLoop f = map (uncurry f) . zipLoop++-- signed angle between 2 vectors+-- https://stackoverflow.com/a/16544330/1779797+-- Note: `isConvex` would remain correct if this returned a value between theta*7/2pi and theta*7/4pi which probably provides an opportunity for optimisation+angle :: (Float,Float) -> (Float,Float) -> Float+angle (x1,y1) (x2,y2) = let dot = x1*x2 + y1*y2 -- cos theta * |v1||v2|+                            det = y2*x1 - x2*y1 -- sin theta * |v1||v2|+                        in atan2 det dot+++-- Approximating 2pi by 7 is reasonable here.+-- The total rotation theoretically must be a multiple of 2pi,+-- so a little generosity doesn't break anything, but might save some cases that would fail due to floating point errors+isConvex :: [(Float,Float)] -> Bool+isConvex ps =+    -- check that it doesn't turn more than one full circle in total+    all (\theta -> (theta <= 7) && (theta > -7)) $+    scanl angleAdd 0 $ -- check that the path's direction is consistent+    zipWithLoop angle $ -- compute angles of turns at each vertex+    filter (/= (0,0)) $ -- discard edges arising from duplicated vertices+    zipWithLoop (\(x1,y1) (x2,y2) -> (x2-x1,y2-y1) ) -- produce vectors for each edge+        ps+  where+    -- Combine angles, but return a value greater than 7 if they have opposite signs+    angleAdd :: Float -> Float -> Float+    angleAdd a b = if signum a*signum b < -0.5 then 10 else a + b++renderComplexPolygon :: [(Float,Float)] -> IO ()+renderComplexPolygon path = if isConvex path+  then GL.renderPrimitive GL.Polygon $ vertexPFs path+  else do+    Triangulation ts <- triangulate TessWindingOdd 0 ( GL.Normal3 0 0 1) combiner+      (ComplexPolygon [ComplexContour [AnnotatedVertex (GL.Vertex3 (realToFrac a) (realToFrac b) 0) () | (a,b) <- path]])+    GL.renderPrimitive GL.Triangles (trisToGLVertices ts)+    return ()++trisToGLVertices ::    [Triangle a] -> IO ()+trisToGLVertices []    = return ()+trisToGLVertices ((Triangle (AnnotatedVertex v1 _) (AnnotatedVertex v2 _) (AnnotatedVertex v3 _)) : rest)+ = do   GL.vertex $ v1+        GL.vertex $ v2+        GL.vertex $ v3+        trisToGLVertices rest+{-# INLINE trisToGLVertices #-}+++vertexPFs ::    [(Float, Float)] -> IO ()+vertexPFs []    = return ()+vertexPFs ((x, y) : rest)+ = do   GL.vertex $ GL.Vertex2 (gf x) (gf y)+        vertexPFs rest+{-# INLINE vertexPFs #-}

@@ -1,5 +1,5 @@ name:           gloss-rendering-version:        1.13.1.2+version:        1.13.2.1 license:        MIT license-file:   LICENSE author:         Elise Huard@@ -35,12 +35,13 @@         Graphics.Gloss.Internals.Rendering.Common         Graphics.Gloss.Internals.Rendering.Picture         Graphics.Gloss.Internals.Rendering.State+        Graphics.Gloss.Internals.Rendering.Polygon    build-depends:           base                          >= 4.8 && < 5         , bmp                           == 1.2.*-        , bytestring                    == 0.11.*-        , containers                    >= 0.5 && < 0.7+        , bytestring                    >= 0.11 && < 0.13+        , containers                    >= 0.5 && < 0.8         , GLUT                          == 2.7.*         , OpenGL                        >= 2.12 && < 3.1