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Support alpha transparency workflow that allows preview in Blender renderer

See original GitHub issue

I’m noticing that in Blender 2.80, adjusting the Principle BSDF’s Base Color A (alpha) value and setting the material’s Blending Mode to Alpha Blend does work on export, but there doesn’t appear to be a way to effectively preview the alpha levels in the Blender renderer(s) using that method, so I have to keep checking after export.

Would it maybe make more sense, if possible, to support using the Principled BSDF + Transparent BSDF through a Mix Shader and adjusting the alpha level with the Mix Shader’s Factor property?

If I’m not mistaken, this is a pretty common node configuration:

I’m no Blender guru, so I may be missing a small detail, but the ability to accurately preview the result in the renderer before export would be very useful.

Issue Analytics

State:
Created 5 years ago
Comments:17 (8 by maintainers)

Top GitHub Comments

1reaction

donmccurdycommented, Aug 30, 2019

“the sorting is all messed up”

Perfect transparent sorting is a Hard Problem in all realtime engines; this is not something an exporter can fix for you… if you would like to share an example we may be able to advise how to work around it.

0reactions

emackeycommented, Aug 30, 2019

You mean I must use different materials for the opaque parts?

Yes, exactly. Complex and robust game engines like Unity may offer ways to support it, but simpler realtime engines will struggle with opaque parts incorrectly marked as translucent.

This has nothing to do with file formats or exporters, so this GitHub issue tracker is not really the correct forum for asking for help on this topic. You could try searching for “alpha blend depth sorting” or similar online.

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