1 files changed, 4 insertions, 0 deletions
diff --git a/math.cginc b/math.cginc
index e2d4169..5becd0e 100755
--- a/math.cginc
+++ b/math.cginc
@@ -105,5 +105,9 @@ float luminance(float3 rgb) {
   return dot(float3(0.2126, 0.7152, 0.0722), rgb);
 }
 
+float4 alpha_blend(float4 src, float4 dst) {
+  return float4(src.rgb * src.a + dst.rgb * (1 - src.a), src.a + dst.a * (1 - src.a));
+}
+
 #endif  // __MATH_INC