Rhino Render not recognizing Image Texture Color Mask or Alpha Channel

I have 3 images of trees setup.

When I look at the scene in rendered mode the color mask works. When I render the scene the black background on the images shows up. Does the Rhino Render engine respect Color Masks and Alpha Channels? Is there an issue with how I setup the render options?

Please see attached image and Rhino file.

TreeRender.3dm (3.6 MB)

Hm - the extracted images are jpgs, but if I create a png with a transparent background the rendering pays attention to that - it seems not to pay attention to the color mask though, which ought to do the job here - I’ll poke at it some more.


Looks like color mask isn’t implemented for Raytraced / Rhino Render.

RH-61836 Color mask for Picture material does not work with Cycles


I did think that the file type may have been the problem so I took one of the trees (one on the right) and created a png but as you say, I did not remove all of the black background on the image. I think it will be an issue with a lot of the images I have when trying to create these light weight sprites.

Thanks for quick review and please let me know what you find!!