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View Full Version : glBlitFramebuffer() from single to multisampled?



Schnulla
09-22-2009, 06:43 AM
Hi,

am I right that it is not possible to use glBlitFramebufferEXT()
to blit a not-multisampled packed depth-stencil buffer to a
multisampled one?

Thanks

Alfonse Reinheart
09-22-2009, 10:53 AM
am I right that it is not possible to use glBlitFramebufferEXT()
to blit a not-multisampled packed depth-stencil buffer to a
multisampled one?

You are right: you cannot do this.

You can blit between two any buffers that have the same number of samples (whether zero or multisampled). And you can blit between two buffers if the dest has zero samples and the source has non-zero (dest is not multisampled and source is). But that's all.

Schnulla
09-22-2009, 12:08 PM
Mhm okay I just wondered why the registry (http://www.opengl.org/registry/specs/EXT/framebuffer_multisample.txt) says:

If SAMPLE_BUFFERS for the read framebuffer is zero and
SAMPLE_BUFFERS for the draw framebuffer is greater than
zero, the value of the source sample is replicated in
each of the destination samples.


For me this does not work here, so I would agree with
you that it is just not possible... or a driver bug.

Alfonse Reinheart
09-22-2009, 12:10 PM
No wait; you're right. It is a driver bug. The spec says that you are allowed to blit from unsampled to multisampled.

Schnulla
09-22-2009, 03:27 PM
Mhm okay should I report this somehow? ^^