Where is the matte property module
You can control matte properties on an object level through the Matte Properties node. In the latest version of After Effects, a new set of core tools has been introduced to expand rotoscoping beyond a brush-only workflow. The Matte object override parameters can affect both the primary and secondary rays similar to Redshift visibility settings but they differ in that matte options cut out and affect the alpha of the rendered image while disabling primary and secondary visibility options for an object would only. This value enables you to alter the alpha contribution (0 to 1, cut out to normal).
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