as far as I know, glInvalidateFramebuffer can be used to prevent expensive copy operations for FBO attachments that are not used anymore after the FBO is unbound for the time being using glBindFramebuffer.
My question now is:
What happens if the FBO we come from shares an attachment with the FBO we switch to (like depth/stencil attachment) ? Is there any benefit from invalidating said attachment before switching away from the old FBO or is it even hurtful (since it is still used by the other FBO).
Problem is the documentation leaves me a littble bit confused whether glInvalidateFramebuffer is about saving FBO-attachment memory or attachment memory or both.