Question by Rs · Apr 17, 2019 at 03:23 PM · graphics shader-replacement drawmesh renderwithshader

Will Camera.RenderWithShader work with Graphics.DrawMesh (and DrawMeshInstanced)?

I have a script that draws a set of meshes in the scene. Graphics.DrawMesh at the moment is called in Update.

I now have to create an effect with a replacement shader that uses an auxiliary camera to render onto a RenderTexture that would later be used for the effect.

RenderWithShader call is done in the OnPreRender method:

 private void OnPostRender()
 {
     if (repShader != null)
     {
         auxCam.RenderWithShader(repShader, "");
     }
 }

I tried OnPostRender too.

And here's how I am drawing in the Update:

 Graphics.DrawMesh(tileMesh, m, tileMaterial, 0, cam, 0, mpb, false, true, false);
 Graphics.DrawMesh(tileMesh, m, tileMaterial, 0, auxCam, 0, mpb, false, false); // to aux camera

where mpb is a MaterialPropertyBlock

Because I have 2 cameras, I am using Graphics.DrawMesh overloads that take a Camera in their parameters. I don't have any minimal complete examples at the moment but I think the question can be reduced to the following:

does Graphics.DrawMesh work only with GameObjects present in the scene or does it also work with Meshes that are rendered with Graphics methods?

If this approach doesn't work, what are the alternatives other than turning meshes into GameObject instances?

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