How to use a Shader with Point Cloud

Ref to GPU particles - start to end animation

I started out with a CPU version (with only 250 000 particles for faster viewing) https://www.babylonjs-playground.com/#U2C1Q6#1

Then I thought I would see what would happen if I tried to do it with a shader. Since a point cloud does not use normals I thought I could use the values in the normals as the end target positions. However I am even more hopeless with shaders than I thought I was and everything goes blank!

https://www.babylonjs-playground.com/#U2C1Q6#2

(comment out lines lines 76 and 85 and you get the start point cloud).

Any shader experts happy to see what they can do?

I’m taking a look!

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I can apply the shader on a mesh with success.
But applying the scene.defaultMaterial to the PCS gives the same result.
So, I guess it’s in the material properties that something is missing.

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Will look into the PCS mesh construction further.

You need two things:

  • tell the material that it should be rendered as points: pcs.mesh.material.pointsCloud = true;
  • set the point size in the vertex shader: gl_PointSize = 2.0;

Here’s a PG with those changes:

https://www.babylonjs-playground.com/#U2C1Q6#4

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Excellent thank you.

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