Hi all, Is there a way to partially update a mesh vertex buffer or to split a vertex buffer into smaller ones? With mesh.updateVerticesData you have to pass the whole vertex buffer of any kind, even if you just need a few vertices to be changed. With low vertex count meshes, this is done very fast…

Thanks @Deltakosh for pointing me to the right direction. I’ve managed to set up a simple system with this but I’ve found an issue: as sson as I call updateDirectly, the buffer data is cleared and I can not continue using it (after calling mesh.updateVerticesData it’s filled again, but the whole poi…

getData is invalidated (this is the local copy and not the GPU copy) to save time. We do not want to sync the local copy if you update the vertex buffer directly (as we assume this is done for perf reason) But the GPU memory is updated and ready to be rendered

But also mesh.getVerticesData(BABYLON.VertexBuffer.ColorKind) returns null after updateDirectly. So is it necessary to create again the color buffer for that mesh if you want to perform any new changes?

all the data are wiped as they are not synced anymore (Again, we don’t want to spend time on syncing things as maybe you are using one single big buffer for all your VBs) So ideally you should get your own copy before updating the data in raw mode

Thanks! Then I’ve stored the data after the first call and I’m using it afterwards. The system works nicely now.

Fantastic and it is really fast now as well :slight_smile:

Partially update a vertexbuffer or split buffers into smaller parts

Questions

Deltakosh March 23, 2020, 7:01pm 2

This is actually supported
You can get the vertexbuffer you want and be able to call:
https://doc.babylonjs.com/api/classes/babylon.vertexbuffer#updatedirectly

Most efficient way to update vertex buffer?

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Partially update a vertexbuffer or split buffers into smaller parts

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