Clarify zero cases of occlusion queries (gpuweb#4062)

Fixes 3895
Vera-999 · Apr 25, 2023 · da4964f · da4964f
1 parent e4a98f9
commit da4964f
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/spec/index.bs b/spec/index.bs
@@ -12002,7 +12002,9 @@ attachments used by this encoder.
 
                 1. Let |passingFragments| be non-zero if any fragment samples passed all per-fragment
                     tests since the corresponding {{GPURenderPassEncoder/beginOcclusionQuery()}}
-                    command was executed.
+                    command was executed, and zero otherwise.
+
+                    Note: If no draw calls occurred, |passingFragments| is zero.
                 1. Write |passingFragments| into
                     |this|.{{GPURenderPassEncoder/[[occlusion_query_set]]}} at index
                     |renderState|.{{RenderState/[[occlusionQueryIndex]]}}.