Draw chasms using vertex pulling

src/Dodge/Render.hs

@@ -145,16 +145,12 @@ doDrawing' win pdata u = do
     glUseProgram fs
     glDrawArrays GL_TRIANGLES 0 (fromIntegral nIndices)
     -- draw chasm shader blocking floor
-    glUseProgram (pdata ^. chasmShader . shaderUINT)
-    glBindVertexArray $ pdata ^. chasmShader . shaderVAO . vaoName
+    glUseProgram (pdata ^. chasmShader)
     glDepthMask GL_FALSE
     glDrawBuffer GL_NONE
     glStencilOp GL_KEEP GL_KEEP GL_INCR
     with 0 $ glClearNamedFramebufferiv (pdata ^. fboBase . _1 . unFBO) GL_STENCIL 0
-    glDrawArrays
-        (_unPrimitiveMode $ pdata ^. chasmShader . shaderPrimitive)
-        0
-        (fromIntegral nchs)
+    glDrawArrays GL_TRIANGLES 0 (fromIntegral nchs)
     withArray [GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2] $
         glNamedFramebufferDrawBuffers (pdata ^. fboBase . _1 . unFBO) 3
     glDepthMask GL_TRUE

src/Dodge/WorldLoad.hs

@@ -1,5 +1,7 @@
 module Dodge.WorldLoad (postUniverseLoadSideEffect) where
 
+import Shader.Parameters
+import Graphics.GL.Core45
 import Control.Lens
 import Control.Monad
 import Data.Preload.Render
@@ -16,8 +18,12 @@ postWorldLoad :: RenderData -> CWorld -> IO CWorld
 postWorldLoad rdata cw = do
     nfloorvxs <- foldM (pokeTile (rdata ^. floorVBO . vboPtr)) 0 (cw ^. cwTiles)
     bufferPokedVBO (rdata ^. floorVBO) nfloorvxs
-    nchasmvxs <- foldM (pokeChasm (rdata ^. chasmVBO . vboPtr)) 0 (cw ^. chasms)
-    bufferPokedVBO (rdata ^. chasmVBO) nchasmvxs
+    let chbo = rdata ^. chasmVBO . vboName
+        chptr = rdata ^. chasmVBO . vboPtr
+    nchasmvxs <- foldM (pokeChasm chptr) 0 (cw ^. chasms)
+    glInvalidateBufferData chbo
+    glNamedBufferStorage chbo (fromIntegral $ 2 * nchasmvxs * floatSize) chptr 0
+    glBindBufferBase GL_SHADER_STORAGE_BUFFER 7 chbo
     return $
         cw & numberFloorVerxs .~ nfloorvxs
             & numberChasmVerxs .~ nchasmvxs