Add trail to bloom

src/Preload/Render.hs

@@ -47,6 +47,10 @@ preloadRender = do
     cslist <- makeShader "twoD/character" [vert,frag] [3,4,2] ETriangles pokeCharStrat
                   >>= addTexture "data/texture/charMap.png"
     basicTweakZShad <- makeShader "twoD/basicTweakZ" [vert,frag] [4,4] ETriangles pokeTriTweakZ
+-- fullscreen shaders
+    fullscreenAlphaHalveShad <- makeShader "fullscreen/alphaHalve" [vert,frag] [2] ETriangleStrip $
+        const cornerListNoCoord
+    pokeArray (_vboPointer $ _vaoVBO $ _shaderVAO fullscreenAlphaHalveShad) $ concat cornerListNoCoord
 -- texture shaders, no textures attached
     fsShad <- makeShader "texture/simple" [vert,frag] [2,2] ETriangleStrip $ const cornerList
     -- note we directly poke the shader vertex data here
@@ -103,6 +107,7 @@ preloadRender = do
         , _textureShader            = textShad
         , _textureArrayShader       = textArrayShad
         , _fullscreenShader         = fsShad
+        , _fullscreenAlphaHalveShader = fullscreenAlphaHalveShad
         , _boxBlurShader            = boxBlurShad
         , _grayscaleShader          = grayscaleShad
         , _spareFBO                 = fbo
@@ -125,6 +130,13 @@ cornerList =
         ,[-1,-1,0,0]
         ,[ 1,-1,1,0]
         ]
+cornerListNoCoord :: [[Float]]
+cornerListNoCoord =
+        [[-1, 1]
+        ,[ 1, 1]
+        ,[-1,-1]
+        ,[ 1,-1]
+        ]
 --------------------end preloadRender
 
 setupFramebufferWithStencil :: IO (FramebufferObject, TextureObject,RenderbufferObject)