   Data transfer inside video memory
  Hy!Is it possible to transfer data from a render target texture into a vertex buffer without a system memory copy?Right now I do it like this:tPositionTexture0.GetTexture().GetData<Vector4>(posTmpArray);vbPosition.SetData<Vector4>(posTmpArray, 0, numParticles);This code is part of a GPU managed particle system with WH geometry instancing. Currently I'm testing it with ~250.000 particles. (20-30 fps) But I want to decrease the CPU load. Any ideas how to do it, or how to avoid the system-mem copy?   
  The most common way to use rendered-data as part of your vertex stream is probably to just use vertex-texture-fetch (i.e. sample from the texture in your vertex shader), but there's also the R2VB trick.In the last particle system I used, it was implemented using both of these techniques (1 or the other) -- a VTF code-path for most cards, and a R2VB code-path on a few other cards.   ;  Thanks a lot! With vertex-texture-fetch it runs !4! times faster.   