Play with floor textures

src/GLHelp.hs

@@ -13,3 +13,10 @@ mglCreate f = do
 
 mglDelete :: (GLsizei -> Ptr GLuint -> IO ()) -> GLuint -> IO ()
 mglDelete f i = with i $ \ptr -> f 1 ptr
+
+checkGLError :: IO ()
+checkGLError = do
+    err <- glGetError
+    case err of
+        0 -> return ()
+        i -> error $ "OpenGL error: " ++ show i