How to use vertex shader

1. If I use shared mesh https://docs.unity3d.com/ScriptReference/MeshFilter-sharedMesh.html all shared mesh gets the same color( for eg all cube will be set blue one is set to blue )
   
   
2. If I use mesh https://docs.unity3d.com/ScriptReference/Mesh-colors.html it throws mesh leak error
   
   
3. If i use mesh = Instantiate(GetComponent().sharedMesh); it clones mesh and makes null in prefab
   
   What is a proper way so that I can use vertex color shader instead of material.
   

 

https://docs.unity3d.com/ScriptReference/MeshRenderer-additionalVertexStreams.html

 

Does the use of Addition Vertex Stream on Mesh Renderer affect batching?

 

Shouldn't.

 

MeshFilter mf = GetComponent<MeshFilter>();
Color32[] newColors = new Color32[mf.sharedMesh.vertices.Length];
for (int vertexIndex = 0; vertexIndex < newColors.Length; vertexIndex++)
{
newColors[vertexIndex] = newColor;
}
Mesh testMesh = mf.sharedMesh;
testMesh.colors32 = newColors;
GetComponent<MeshRenderer>().additionalVertexStreams = testMesh;
testMesh.UploadMeshData(true);

Can you suggest how to use it, I have been using the above way but color not changing?

 

Hmm, seems I was wrong about additionalVertexStreams not breaking batching. I seem to remember it didn't use to, but a quick search brought up a bunch of bugs with the features that have popped up over the last few years. I have a memory of an old tutorial (Unity 4.0 era?) that used it as an early way to do "instanced" meshes (ie: they still got batched, real instancing didn't exist yet), but maybe I'm mis-remember it.

There's also a comment on twitter from @jbooth complaining about them being broken if you're trying to add vertex colors to a mesh that doesn't already have them. Not sure if that ever got fixed or not.

 

There are a number of bugs with additionalVertexStreams. I don't think they got much use. Ideally, we should just be able to save a mesh in the scene, without saving it to disk. That would greatly reduce the need for additionalVertexStreams, as well as fix a ton of workflow issues.