Separate value for each vertex for instances?

[Blake]

Hello, I’m wondering if there is a way to specify a separate value for each vertex when setting a custom buffer for mesh instances? All the examples I could find are using the same value for each vertex: Instances | Babylon.js Documentation

[Evgeni_Popov]

Welcome aboard!

It’s not possible to have per vertex per instance data using an attribute. You can do it using a texture that will lookup the data by using the gl_VertexID / gl_InstanceID predefined variables. See for eg:

Using .glb model with instantiation and vertex colors

I don’t think you will be able to change the color of each vertex for each instance easily. As @Deltakosh said, there’s a way to set a color per instance (so the same for all vertices of the instance) but not to set a color per vertex per instance. You could do it by using a custom shader and using the gl_VertexID and gl_InstanceID predefined variables to lookup the color you want in a texture you would create in a pre-process and pass to the shader. Something like: https://playground.babylon…

[Blake]

TYVM those indexes & playground are very helpful indeed!

Hmm, it looks like the gl_VertexID indexes are in a different order than the vertex data gotten and set by getVerticesData() and setVerticesData(), but I used setVerticesData() to create my own vertexIndex attribute and that is working well.