Understanding Matte Compositing in TouchDesigner

The Matte operation in the Composite TOP is used to control the transparency of one image using another image as a mask. Instead of blending two images together, Matte decides which parts of the foreground remain visible and which parts become transparent. This makes it one of the most useful operations for masking effects, revealing animations, creating transitions, and isolating specific areas of an image without permanently editing the source.

A common workflow is using a grayscale texture or animated mask to reveal text, particles, or video over time. White areas of the matte keep the foreground visible, black areas hide it, and gray values create smooth transparency between the two. Because the mask can be generated from almost any TOP, including Noise, Ramp, Feedback, or Render TOPs, Matte opens up endless creative possibilities for procedural visuals while keeping your network flexible and easy to adjust.