Expand description
Compose a foreground RenderTexture against a separately-
generated alpha mask texture (M-VEC.4..6 / AUT-56..58).
The primitive: output.rgba = (foreground.rgb, foreground.a * mask.a). Replaces the inline-SDF clip pipeline for vector-driven
masks; the mask itself comes from
MaskTexturePipeline
or
PathMaskTexturePipeline
(or the M-DYN.2 cache).