@@ -0,0 +1,307 @@
+package com.coillighting.udder.blend;%0A%0Apublic class MaskBlendOp implements BlendOp %7B%0A%0A    public float blend(float background, float foreground) %7B%0A%09%09float val = 0.0f;%0A%09%09if (foreground %3C 0.5f)%7B%0A%09%09%09val = background%0A%09%09%7D%0A        return val;%0A    %7D%0A%0A    public String toString() %7B%0A        return %22mask%22;%0A    %7D%0A%0A%7D%0A

mask blending mode