Render bezier curves using distance fields

src/Picture/Data.hs

@@ -22,7 +22,7 @@ import Data.Traversable
 
 data RenderType
     = RenderPoly [(Point3,Point4)]
-    | RenderBezQ [(Point3,Point4,Point3)]
+    | RenderBezQ [(Point3,Point4,Point4)]
     | RenderText [(Point3,Point4,Point3)]
     | RenderArc  (Point3,Point4,Point4)
     | RenderLine [(Point3,Point4)]
@@ -75,7 +75,7 @@ data Picture
     = Blank
     | Text Int String
     | Polygon Int [Point2]
-    | BezierQuad Int [(Point2,RGBA,Point2,Float)]
+    | BezierQuad Int [(Point2,RGBA,Point2,Point2)]
     | PolygonCol Int [(Point2,RGBA)]
     | Circle Int RGBA RGBA Float
     | ThickArc Int Float Float Float Float

src/Picture/Preload.hs

@@ -50,7 +50,7 @@ preloadRender = do
                                 "data/texture/charMap.png"
 
     bezierQuadShader
-           <- makeShader "bezierQuad" [vert,geom,frag] [(0,3),(1,4),(2,3)]    Triangles pokeBezQStrat
+           <- makeShader "bezierQuad" [vert,frag] [(0,3),(1,4),(2,4)]    TriangleStrip pokeBezQStrat
 
 --the following vbo is set up to contain one fixed vertex
     dummyvbo <- genObjectName
@@ -84,7 +84,9 @@ cleanUpRenderPreload pd = do
 
 {-# INLINE pokeBezQStrat #-}
 pokeBezQStrat :: RenderType -> [[[Float]]]
-pokeBezQStrat (RenderBezQ vs) = fmap (\((x,y,z),(r,g,b,a),(s,t,v)) -> [[x,y,z],[r,g,b,a],[s,t,v]]) vs
+pokeBezQStrat (RenderBezQ vs) = fmap (\((x,y,z),(r,g,b,a),(s,t,u,v)) -> [[x,y,z],[r,g,b,a],[s,t,u,v]]
+                                     ) 
+                                     vs
 pokeBezQStrat _ = []
 
 {-# INLINE pokeTriStrat #-}

src/Picture/Tree.hs

@@ -20,7 +20,7 @@ picToLTree mx (PolygonCol i vs)
 picToLTree mx (BezierQuad i vs) 
     = filtB mx i $ LLeaf $ RenderBezQ $ zip3 (map zeroZ ps) cols rs
         where (ps,cols,offps,rads) = unzip4 vs
-              rs = zipWith (\(x,y) z -> (x,y,z)) offps rads
+              rs = zipWith (\(x,y) (z,w) -> (x,y,z,w)) offps rads
                                       
 picToLTree mx (Circle i colC colE r)
     = filtB mx i $ LLeaf $ RenderEllipse [( (-r, r,0), colC)