Fix memory alignment of outline spans.

Some CPU architectures require all memory accesses to be naturally aligned. We read polygon outline spans in pairs, so we need two underflow spans. b/37478805 Change-Id: If74fd59654fb6fa56cbed93122b496b9e86dda06 Reviewed-on: https://swiftshader-review.googlesource.com/9528Reviewed-by: Nicolas Capens <capn@google.com> Tested-by: Nicolas Capens <capn@google.com>

Fix memory alignment of outline spans.
ac6e751f · Nicolas Capens · 7319d3ec · ac6e751f
Commit ac6e751f authored Apr 28, 2017 by Nicolas Capens
Hide whitespace changes
Inline Side-by-side

Showing with 4 additions and 2 deletions

Primitive.hpp src/Renderer/Primitive.hpp +4 -2

No files found.
--- a/src/Renderer/Primitive.hpp
+++ b/src/Renderer/Primitive.hpp
@@ -69,9 +69,11 @@ namespace sw
 			unsigned short right;
 		};
-		Span outlineUnderflow;
+		// The rasterizer adds a zero length span to the top and bottom of the polygon to allow
+		// for 2x2 pixel processing. We need an even number of spans to keep accesses aligned.
+		Span outlineUnderflow[2];
 		Span outline[OUTLINE_RESOLUTION];
-		Span outlineOverflow;
+		Span outlineOverflow[2];
 	};
 }