koobas.hobune.stream
Difference between Blit and DrawMeshNow on RenderTexture
Hi
I have some code that uses Blit to run a set of pixel shaders from a texture through a set of RenderTargets. The destination of each Blit is reused as a source for the next one. That code works very well but it doesn't run on all pixels, some of which I don't care to calculate. So I am trying to change the code to use DrawMeshNow or GL.Begin()..., but that doesn't seem to work. It looks like reusing the RT as source texture for the next shader is not working.
Here is the old code:
material.SetTexture ("SourceTexture", source);
destination.DiscardContents();
Graphics.Blit (null, destination, material, 0);
Here is the new code:
material.SetTexture ("SourceTexture", source);
RenderTexture.active = destination;
destination.DiscardContents();
material.SetPass(0);
Graphics.DrawMeshNow(surroundingMesh, Matrix4x4.identity);
Each time the shader is executed, source and destination are swapped. I don't understand why this is not working with DrawMesgNow and I don't know what I would be missing. It looks like the shader is properly executed but runs from an older source.
I have further discovered that I need only the first Blit call, after that all the other calls can be Draw$$anonymous$$eshNow. So there is something particular to Blit() that makes all the other calls work and that I am not doing. For further info, I place the following GL calls before doing the effect:
GL.Push$$anonymous$$atrix();
GL.LoadOrtho();
GL.LoadPixel$$anonymous$$atrix();
This is all done during the Update() call.
