Transparency & Materials question

In our Vircadia class some asked how to make transparent materials.

I tried to follow current documentation, but it only covers Blender 2.79, using this I was able to have a transparency just specifying alpha in the blender engine as suggested by this page PBR Materials Guide β€” Vircadia Documentation, is there any possibility to have a similar documentation for current Blender?

Second question, I tried to understand how the new material object work, but was not able to understand the current documentation as stated in the first post of The secret life of Material Entities ,

I totally didnt understand how I can control materials of my models, I suspected that the material object would be able to solve the problem of transparency with Blender 2.8 2.9, but could not understand how to use it.

It would be nice if there is a video explaining that on a similar cube like that in the photo with just a semitransparent stripe. Thanks for any hints.

With Blender 2.93.5, I eventually tried the following

  • Setting alpha in principled node to around 0.5
  • alpha blend just to be able to see it in blender
  • export as glb
    It seems working. Is that the correct workflow?

Still missing some tutorials on Material Entities.

Have you checked the Material application? Maybe this could help to figure a few things.
(You will find it in the β€œMore…” application)

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Hi, I think You are on the right path, for the cube thing (some solid and some semi transparent) you could do it as 2 different materials or use a texture for the alpha channel, but as always, there is a few caveats :slight_smile:

  • you have the to use the same texture as used for color(albedo) channel for the alpha channel, in blender you can use 2 different textures but Vircadia will always use the color channel one.
  • I think there is an issue where the colorspace of the alpha channel is wrong in the *.glb export (or our importer) so it may not look the same exactly as in blender.
  • using alpha blend mode(gradient transparency) on self-occluding models (like the cube) sometimes look weird depending on the angle you look at it, you can turn on "Backface culling) but that is usually not desired for objects where you can see the inside.

Other that that, if you use *.glb the setting you set in blender (like blend mode or clipping threshold) should be reflected directly in Vircadia, try this one to see:
same file exprted as *.glb:

Regarding the Material Entities guide, what part exactly could you not follow? I would like to improve it if there are some things that are not easy to understand

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I eventually was able to make it work, thanks to @alezia.kurdis for pointing me to the application.
It really simplify the operation, but still is missing a video or a tutorial explaining how to use it on a simple case, a cube with two materials would be a good tutoring point.
Recapping what should probably be added to documentation is a clear reference to this app, and possibly a live video 3 minutes maybe can be enough to teach how to use it. I can do it, but usually do videos in Italian for my students. Anyway, I now think I have understood how to manage this powerful possibility. Thanks @Silverfish for that :slight_smile: