The Blend Control Mask API allows a client to submit a masking layer that is used to control the blending between video see-through and application layer images. The API was finalized and moved out of the experimental API in the Varjo Base 3.3.0 release.
Blend Control Mask can be used to extend or restrict the mask provided by the Chroma key feature. The mask layer can be provided either with the main application layer or as a separate rendering application for masking alone.
See MaskingTool in the examples folder of the experimental SDK for information on how to implement masking in your own client application. The example application shows how to render the mask to the texture buffer and submit it to Varjo Compositor, either to mask the video pass-through image or to restrict or extend the chroma key mask. The example application uses simple plane shapes, but you can easily extend it to render more complex shapes.
Chroma Key Masking API
The Blend Control Mask API deprecates the previously available experimental Chroma Key Masking API.