Implement (not fully working) alternate shadow volumes

src/Shader/Data.hs

@@ -27,6 +27,7 @@ module Shader.Data
     , geom
     , frag
     ) where
+import Data.Vector (Vector)
 import Graphics.Rendering.OpenGL
 import Foreign
 import Control.Lens
@@ -36,7 +37,7 @@ data FullShader = FullShader
     , _shadVAO  :: VAO
     , _shadPrim :: EPrimitiveMode
     , _shadTex  :: Maybe ShaderTexture
-    , _shadUnis :: [UniformLocation]
+    , _shadUnis :: Vector UniformLocation
     }
 {- | Vertex array object: contains the reference to the object,
 and its buffer targets.  -}