Make bloom trail last for at most one frame

src/Dodge/Render.hs

@@ -82,20 +82,24 @@ doDrawing pdata w = do
     depthMask $= Enabled
     --bindFramebuffer Framebuffer $= (fst3 $ _fbo2 pdata)
     bindFramebuffer Framebuffer $= (fst $ _fboFourth1 pdata)
-    viewport $= (Position 0 0, Size 600 600)
+    viewport $= (Position 0 0, Size 300 300)
     depthFunc $= Just Always
     --blend $= Disabled
     textureBinding Texture2D $= Just (snd $ _fboBloom pdata)
-    textureFilter Texture2D $= ((Linear',Nothing) , Linear')
     --clear [ColorBuffer]
     --blendFunc $= (SrcAlpha,OneMinusSrcAlpha)
     --blendFuncSeparate $= ((Zero,One), (Zero,SrcAlpha))
     --drawShader (_fullscreenAlphaHalveShader pdata) 4
     --blendFunc $= (SrcAlpha,OneMinusSrcAlpha)
     --drawShader (_bloomBlurShader pdata) 4
-    blendFunc $= (One,Zero)
-    drawShader (_fullscreenShader pdata) 4
-    --replicateM_ 5 $ pingPongBetween (_fboFourth1 pdata) (_fboFourth2 pdata) (_bloomBlurShader pdata)
+    --blendFuncSeparate $= ((Zero,One),(Zero,SrcAlpha))
+    blendFunc $= (One,One)
+    blendEquation $= FuncReverseSubtract
+    drawShader (_fullscreenAlphaHalveShader pdata) 4
+    blendFunc $= (SrcAlpha,OneMinusSrcAlpha)
+    blendEquation $= FuncAdd
+    drawShader (_bloomBlurShader pdata) 4
+    replicateM_ 5 $ pingPongBetween (_fboFourth1 pdata) (_fboFourth2 pdata) (_bloomBlurShader pdata)
     --replicateM_ 5 $ pingPongBlur pdata
     --blend $= Enabled
     viewport $= (Position 0 0, Size (round $ fst wins) (round $ snd wins))
@@ -122,8 +126,6 @@ doDrawing pdata w = do
     --drawShader (_fullscreenShader pdata) 4
     --textureBinding Texture2D $= Just (snd3 $ _fbo2 pdata)
     textureBinding Texture2D $= Just (snd $ _fboLighting pdata)
-    textureFilter Texture2D $= ((Linear',Just Linear') , Linear')
-    generateMipmap' Texture2D
     blend $= Enabled
     blendFunc $= (Zero, OneMinusSrcAlpha)
     drawShader (_fullscreenShader pdata) 4