Different meshes that share the same material, batching drawcalls?

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Here’s a CompositeMesh class which is doing something along the lines of the “static batching” of Unity:

https://playground.babylonjs.com/#46PNW4#6

It will create some big vertex buffers for position/normal/uv to hold all the meshes+their thin instances you pass when calling addMesh. If you update the position/rotation/scaling of the mesh or the matrices of the thin instances (or thinInstanceCount) you will need to call update() to refresh the buffers, which can be slow if there are a lot of data to regenerate.

Of course, if you use a lot of meshes and/or thin instances, the vertex buffers can get very big. It’s a trade-off between using more memory/having better perf.

Using this class in your PG:

https://playground.babylonjs.com/#STN960#9

If you want the thin instance picking to work with the composite mesh, you must:

  • enable thin instance picking on the meshes that have thin instances
  • override the scene.pointerDownPredicate property so that it does not check that the mesh is enabled: when using the CompositeMesh class, the meshes you pass to the addMesh method are disabled so that they are not displayed by Babylon

See:

https://playground.babylonjs.com/#STN960#7

Regarding the update() method being slow, you could improve it by only updating the data that you know have changed.

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