TextureCube support.

1 files changed, 79 insertions, 2 deletions

diff --git a/src/LambdaCube/GL/Data.hs b/src/LambdaCube/GL/Data.hs
index 56955d1..952e14a 100644
--- a/src/LambdaCube/GL/Data.hs
+++ b/src/LambdaCube/GL/Data.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE LambdaCase #-}
 module LambdaCube.GL.Data where
 
 import Control.Applicative
@@ -15,6 +16,7 @@ import qualified Data.Vector.Storable as SV
 --import Control.DeepSeq
 
 import Graphics.GL.Core33
+import Graphics.GL.EXT.TextureFilterAnisotropic
 import Data.Word
 import Codec.Picture
 import Codec.Picture.Types
@@ -59,7 +61,10 @@ arrayType buf arrIdx = arrType $! bufArrays buf V.! arrIdx
 
 -- Texture
 disposeTexture :: TextureData -> IO ()
-disposeTexture (TextureData to) = withArray [to] $ glDeleteTextures 1
+disposeTexture (Texture2DName to) = withArray [to] $ glDeleteTextures 1
+
+disposeTextureCube :: TextureCubeData -> IO ()
+disposeTextureCube (TextureCubeName to) = withArray [to] $ glDeleteTextures 1
 
 -- FIXME: Temporary implemenation
 uploadTexture2DToGPU :: DynamicImage -> IO TextureData
@@ -104,4 +109,76 @@ uploadTexture2DToGPU' isFiltered isSRGB isMip isClamped bitmap' = do
                 _   -> error "unsupported texture format!"
         glTexImage2D GL_TEXTURE_2D 0 internalFormat (fromIntegral w) (fromIntegral h) 0 dataFormat GL_UNSIGNED_BYTE $ castPtr ptr
     when isMip $ glGenerateMipmap GL_TEXTURE_2D
-    return $ TextureData to
+    return $ Texture2DName to
+
+
+compatibleImage :: DynamicImage -> DynamicImage
+compatibleImage bitmap' = case bitmap' of
+          ImageRGB8 i@(Image w h _)   -> bitmap'
+          ImageRGBA8 i@(Image w h _)  -> bitmap'
+          ImageYCbCr8 i@(Image w h _) -> ImageRGB8 $ convertImage i
+          di -> ImageRGBA8 $ convertRGBA8 di
+
+imageFormat :: Bool {- ^ is SRGB -} -> Int {- number of channels -} -> (GLenum,GLint) {- ^ dataFormat,internalFormat -}
+imageFormat isSRGB 3 = (GL_RGB , fromIntegral $ if isSRGB then GL_SRGB8        else GL_RGB8)
+imageFormat isSRGB 4 = (GL_RGBA, fromIntegral $ if isSRGB then GL_SRGB8_ALPHA8 else GL_RGBA8)
+imageFormat isSRGB _ = error "unsupported texture format!"
+
+uploadCubeMapToGPU :: [DynamicImage] -> IO TextureCubeData
+uploadCubeMapToGPU = uploadCubeMapToGPU' True False True True
+
+
+uploadCubeMapToGPU' :: Bool -> Bool -> Bool -> Bool -> [DynamicImage] -> IO TextureCubeData
+uploadCubeMapToGPU' isFiltered isSRGB isMip isClamped (bitmap':bitmaps') = do
+    -- The six faces of the cube are represented by six subtextures that must be square and of the same size.
+
+    let (bitmap,side):bitmaps =
+            zip (map compatibleImage (bitmap':bitmaps'))
+                [GL_TEXTURE_CUBE_MAP_POSITIVE_X .. GL_TEXTURE_CUBE_MAP_NEGATIVE_Z]
+
+    glPixelStorei GL_UNPACK_ALIGNMENT 1
+    to <- alloca $! \pto -> glGenTextures 1 pto >> peek pto
+    glBindTexture GL_TEXTURE_CUBE_MAP to
+    let (width,height) = bitmapSize bitmap
+        bitmapSize (ImageRGB8 (Image w h _)) = (w,h)
+        bitmapSize (ImageRGBA8 (Image w h _)) = (w,h)
+        bitmapSize _ = error "unsupported image type :("
+        withBitmap (ImageRGB8 (Image w h v)) f = SV.unsafeWith v $ f (w,h) 3 0
+        withBitmap (ImageRGBA8 (Image w h v)) f = SV.unsafeWith v $ f (w,h) 4 0
+        withBitmap _ _ = error "unsupported image type :("
+        texFilter = if isFiltered then GL_LINEAR else GL_NEAREST
+        wrapMode = case isClamped of
+            True    -> GL_CLAMP_TO_EDGE
+            False   -> GL_REPEAT
+        (minFilter,maxLevel) = case isFiltered && isMip of
+            False   -> (texFilter,0)
+            True    -> (GL_LINEAR_MIPMAP_LINEAR, floor $ log (fromIntegral $ max width height) / log 2)
+
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_MIN_FILTER $ fromIntegral minFilter
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_MAG_FILTER $ fromIntegral texFilter
+    glGetEXTTextureFilterAnisotropic >>= \case
+        False -> return ()
+        True  -> alloca $ \ptr -> do
+                    poke ptr 0
+                    glGetIntegerv GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT ptr
+                    max <- peek ptr
+                    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_MAX_ANISOTROPY_EXT max
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_WRAP_S $ fromIntegral wrapMode
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_WRAP_T $ fromIntegral wrapMode
+
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_BASE_LEVEL 0
+    glTexParameteri GL_TEXTURE_CUBE_MAP GL_TEXTURE_MAX_LEVEL $ fromIntegral maxLevel
+    fmt <- withBitmap bitmap $ \(w,h) nchn 0 ptr -> do
+        let fmt@(dataFormat,internalFormat) = imageFormat isSRGB nchn
+        -- Graphics.GL.Core42.glTexStorage2D GL_TEXTURE_CUBE_MAP (maxLevel + 1) internalFormat (fromIntegral w) (fromIntegral h)
+        -- glTexImage2D :: MonadIO m => GLenum -> GLint -> GLint -> GLsizei -> GLsizei -> GLint -> GLenum -> GLenum -> Ptr a -> m ()
+        glTexImage2D side 0 internalFormat (fromIntegral w) (fromIntegral h) 0 dataFormat GL_UNSIGNED_BYTE $ castPtr ptr
+        return (fmt,(w,h))
+    forM_ bitmaps $ \(b,targ) -> withBitmap b $ \wh nchn 0 ptr -> do
+        let (dataFormat,internalFormat) = case imageFormat isSRGB nchn of { x | (x,wh)==fmt -> x; _ -> error "incompatible images" }
+        glTexImage2D targ 0 internalFormat (fromIntegral $ fst wh) (fromIntegral $ snd wh) 0 dataFormat GL_UNSIGNED_BYTE $ castPtr ptr
+
+    when isMip $ glGenerateMipmap GL_TEXTURE_CUBE_MAP
+    -- A GL_INVALID_OPERATION error will be generated if target is GL_TEXTURE_CUBE_MAP,
+    -- and not all cube-map faces are initialized and consistent.
+    return $ TextureCubeName to