Add more mutability

src/Shader.hs

@@ -5,6 +5,7 @@ module Shader
     , drawShader
     , freeShaderPointers
     , drawShaderLay
+    , drawShaderLay'
     , shadVBOptr
     ) where
 --import Geometry.Data
@@ -57,13 +58,6 @@ bindShaderLay shads = mapM_ (uncurry f) . IM.toList
   where
     f lay counts = sequence_ $ bindArrayBuffersLayer lay <$> counts <*> (_vaoVBO . _vshaderVAO <$> shads)
 
---bindShader :: PicShads VShader -> PicShads Int -> IO ()
-----bindShader shads counts = sequence_ $ bindArrayBuffers <$> counts <*> (_vaoVBO . _vshaderVAO <$> shads)
---bindShader shads count = do
---    s <- picShadToMV shads
---    c <- picShadToUMV count
---    bindShader' s c
-
 bindShader :: MV.MVector (PrimState IO) VShader -> UMV.MVector (PrimState IO) Int -> IO ()
 bindShader shads counts = MV.imapM_ f shads
   where
@@ -86,6 +80,18 @@ drawShaderLay l fs i = do
         _   -> return ()
     glDrawArrays (marshalEPrimitiveMode $ _vshaderDrawPrimitive fs) (fromIntegral $ l*numSubElements) (fromIntegral i)
 
+drawShaderLay' :: Int -> UMV.MVector (PrimState IO) Int -> Int -> VShader -> IO ()
+{-# INLINE drawShaderLay' #-}
+drawShaderLay' l countsVector index fs = do 
+    i <- UMV.read countsVector index
+    currentProgram $= Just (_vshaderProgram fs)
+    bindVertexArrayObject $= Just (_vao $ _vshaderVAO fs)
+    case _vshaderTexture fs of 
+        Just ShaderTexture{_textureObject = txo}
+            -> textureBinding Texture2D $= Just txo
+        _   -> return ()
+    glDrawArrays (marshalEPrimitiveMode $ _vshaderDrawPrimitive fs) (fromIntegral $ l*numSubElements) (fromIntegral i)
+
 drawShader :: FullShader -> Int -> IO ()
 {-# INLINE drawShader #-}
 drawShader fs i = do