1 files changed, 57 insertions, 0 deletions
diff --git a/Graphics/Glyph/Shaders.hs b/Graphics/Glyph/Shaders.hs
new file mode 100644
index 0000000..9a85e1a
--- /dev/null
+++ b/Graphics/Glyph/Shaders.hs
@@ -0,0 +1,57 @@
+module Graphics.Glyph.Shaders where
+
+import Graphics.Rendering.OpenGL
+import qualified Data.ByteString as BS
+import Control.Monad
+import Data.Maybe
+
+loadShader :: ShaderType -> FilePath -> IO (String, Maybe Shader)
+loadShader typ path = do
+    shader <- createShader typ
+    ( shaderSourceBS shader $= ) =<< BS.readFile path
+    compileShader shader
+
+    ok <- get (compileStatus shader)
+    infoLog <- get (shaderInfoLog shader)
+
+    unless ok $
+        deleteObjectNames [shader]
+
+    return ( infoLog, if not ok then Nothing else Just shader );
+
+
+loadShaders :: [(ShaderType,FilePath)] -> IO [(String, Maybe Shader)]
+loadShaders = mapM ( uncurry loadShader )
+
+workingShaders :: [(a, Maybe Shader)] -> [Shader]
+workingShaders lst = map (fromJust . snd) (filter (isJust . snd) lst)
+
+createShaderProgram :: [Shader] -> IO (String, Maybe Program)
+createShaderProgram shaders = do
+    p <- createProgram
+    mapM_ (attachShader p) shaders
+    linkProgram p
+
+    ok <- get $ linkStatus p
+    info <- get $ programInfoLog p
+
+    unless ok $
+        deleteObjectNames [p]
+
+    return ( info, if not ok then Nothing else Just p )
+
+getUniform :: Uniform a => String -> IO (Maybe (StateVar a))
+getUniform name =
+    get currentProgram >>= (\pr -> case pr of
+            Just p -> liftM (Just . uniform) (get $ uniformLocation p name)
+            Nothing -> return Nothing )
+
+getUniformForProgram :: Uniform a => String -> Program -> IO (StateVar a)
+getUniformForProgram name prog =
+    liftM uniform (get $ uniformLocation prog name)
+    
+
+getUniformLocation :: String -> IO (Maybe UniformLocation)
+getUniformLocation name =
+    get currentProgram >>= maybe (return Nothing) (\prog ->
+        liftM Just (get $ uniformLocation prog name) )