SP default gltf mode dose not support tranlucency, glass item is display wrong. I saw the bbl’s shader, bbl sampler channel a when SS_USE_GLTF_TEXTURES and b when else, then I export two map for B and A channel.
Translucency off:
They are both not looking like glass, anyone know how to setting the parameters of pbr material?
Looking forward to your reply!
I upload glb file and translucency map with channel R/G/B/A。 GLB.zip (11.0 MB)
@Moriy, part of what you want to do would be to enable Transmission on the material. To do this, you would enable Refraction and Use Albedo to tint surface Transparency at minimum:
You can see that just enabling these goes a long way with the bottles. The glasses are another story, unfortunately. This is due to the fact that you should be able to see the edges of the inside surfaces of the glass in the stem. Unfortunately, there’s no quick and easy toggle to enable this. You will need to rely on a few techniques. First, you should bake out a thickness texture for all of your glass which will help to control the amount of refraction each item has based on its thickness.
Then you will likely need to do some mesh splitting where you can hide a seam on your glass mesh. Separate the faces that make up the inside of the glass from those that make up the outside of the glass. Keep backface culling on and add in some refraction on the inside. Dial the translucency on the outside faces down, and you can go things like drop the alpha on the exterior faces a bit. The goal here is to see through the outside so you can see faces from the inside of the wine glass.
You will also want to look at your roughness texture as it seems too high for the glass material and ice. You want your labels to be rough, but the glass elements in the scene should have very low roughness to accentuate the environment reflections. For the ice, you want it slightly more rough than the glass but nowhere near what you have on the labels. The foil will want to be somewhere in the middle where you get some surface reflections, but softer ones. You can see in the image above, I dropped the overall roughness on the material to get th eglass to have better reflections, but that adversely affected the label. You will just need to adjust the levels in your roughness texture to make sure the items that need to be reflective are darker tones in your roughness map.
I hope this helps point you in a direction, but please feel free to ping back with more questions.
An example of where we made a complex mesh made of glass and liquid can be found in this playground. This was done a few years ago, so some of the engine and glTF specs have changed around this example. But it can still be used to tear down and see how it was done to adapt.
