This rendering looks very nice!
It should not be hard to add this as a new volume rendering option. This is required for photorealistic volume rendering (a.k.a. “cinematic rendering”), too - there the RGB array is filled in quickly and approximately using AI-based segmentation, making vessels appear red, bone off-white, soft-tissues brown, etc.
It would be nice to use this in the segmentation displayable manager, too. For this we should have the option of generating opacity volume from the segmentation’s binary labelmap and compute smooth gradients. Smoothing the binary labelmap would be easy, but slow and it would double the memory usage. It would be better to improve the GPU raycaster’s gradient computation to use a small local neighborhood. Eventually, binary labelmap volume rendering as RGB should be a built-in feature of the GPU volume raycast mapper.
Do you use the GPU volume mapper’s labelmap masking features (specify a lookup table for input labelmap mask and mask blend factor controls how much coloring is applied from the mask) or you generate an RGBA volume from scratch?