Binding a VBO to a FBO

Excuse my novice question, but is there or will there be a way to render into a FBO that is mapped to a VBO and specify a swizzle so e.x. the rendering components r,g goes into the VBO x,z without going back to CPU mem ?

Create PBO buffer
Create FBO (rgba32f if you need full precission)
Render to FBO
Readback to PBO
Rebind PBO as VBO


ok. So the swizzle then can be made with ordinary GLSL and you are sure then the rendered data is never transferred to GPU mem…

great news…

Yep… swizling can be done by fragment shader. Framebuffer data will be copied to another part of GPU memory (PBO memory).