Blitting onto single rendertexture in Tex2DArray

I have a setup where I blit into a rendertexture using a material (

Graphics.Blit(source,dest,matA)

). The rendertexture is associated with another material, matB, and everything works. I'd however like this to be instanced, so I can use the same material, matB, on multiple objects but only blit onto the texture of one of them at a time. Everything apart from the blit works, by making my rendertextures Tex2DArrays, setting an instanced slice index and using UNITY_SAMPLE_TEX2DARRAY and the like in matB to sample the right slice for each object.

What I can't figure out is how to now do the blitting on only a single RenderTexture in the Tex2DArray, to only affect a single slice. Graphics.Blit has a

destDepthSlice

, which seems like what I need, except that I cannot use that as the same time as a source, dest and material it seems.

So what is the right (GPU-side/efficient) approach? Use copytexture somehow? Set up a different pass in matB for each slice? Or something else entirely? Thanks for your help.

 

Never mind; turns out that unlike what the Graphics.Blit documentation claims, you can actually do

Code (CSharp):

1. Graphics.Blit(source,destArray,mat,-1,index);

to blit from a normal rendertexture (

source

) to a specific slice index of a Tex2DArray (

destArray

) using a material, as long as you also set a source slice (here -1, since the source is not an array).