Need better examples for vertex shaders in 3d meshes

[viridia]

Currently we have one example showing how to write a vertex shader, and that example is for 2d meshes. Most custom shader examples only define a fragment shader, and use the default vertex shader. I'd like to see examples of vertex shaders for 3d meshes.

A good example should show:

• What does the vertex input data look like?
• What does the vertex output data look like?
• What are the minimum calculations that need to happen (position and normal calculation, etc.)
• For extended materials, what calculations can be skipped because they are already done in the base material? Assume that we're using StandardMaterial as a base.

[viridia]

Actually, turns out there was one example that I missed that does have a vertex shader.