SL-18190 Fix alpha not playing nice with water surface by split LLDrawPoolAlpha into two passes, one above water, one below water, and clip against water plane. Currently brute forces two complete alpha passes, still need to cull against water plane and add support for fullbright shaders.

1 files changed, 14 insertions, 11 deletions

diff --git a/indra/newview/lldrawpool.h b/indra/newview/lldrawpool.h
index 2b7ace7ae5..620438bb1b 100644
--- a/indra/newview/lldrawpool.h
+++ b/indra/newview/lldrawpool.h
@@ -49,29 +49,32 @@ public:
 	{
 		// Correspond to LLPipeline render type
         // Also controls render order, so passes that don't use alpha masking/blending should come before
-        // other passes and occlusion culling should happen just before rendering alpha masked passes
-        // in order to take advantage of hierarchical Z
-        // NOTE: Keep in sync with gPoolNames
+        // other passes to preserve hierarchical Z for occlusion queries.  Occlusion queries happen just
+        // before grass, so grass should be the first alpha masked pool.  Other ordering should be done
+        // based on fill rate and likelihood to occlude future passes (faster, large occluders first).
+        //  
 		POOL_SIMPLE = 1,
 		POOL_GROUND,
 		POOL_FULLBRIGHT,
 		POOL_BUMP,
-		POOL_MATERIALS,
-		POOL_TERRAIN,	
-		POOL_SKY,
-		POOL_WL_SKY,
+		POOL_TERRAIN,
+        POOL_MATERIALS,
+        POOL_GRASS,
 		POOL_TREE,
 		POOL_ALPHA_MASK,
 		POOL_FULLBRIGHT_ALPHA_MASK,
-		POOL_GRASS,
+        POOL_SKY,
+        POOL_WL_SKY,
 		POOL_INVISIBLE, // see below *
 		POOL_AVATAR,
 		POOL_CONTROL_AV, // Animesh
-		POOL_VOIDWATER,
-		POOL_WATER,
 		POOL_GLOW,
-		POOL_ALPHA,
+		POOL_ALPHA_PRE_WATER,
+        POOL_VOIDWATER,
+        POOL_WATER,
+        POOL_ALPHA_POST_WATER,
 		POOL_PBR_OPAQUE,
+        POOL_ALPHA, // note there is no actual "POOL_ALPHA" but pre-water and post-water pools consume POOL_ALPHA faces
 		NUM_POOL_TYPES,
 		// * invisiprims work by rendering to the depth buffer but not the color buffer, occluding anything rendered after them
 		// - and the LLDrawPool types enum controls what order things are rendered in