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View Full Version : NVIDIA Internal Format Query 2 oddness



Alfonse Reinheart
02-09-2013, 08:38 PM
I'm using NVIDIA's 310.90 drivers on a GeForce GT250. And I'm testing out ARB_internalformat_query2, to see what you get when you try different things.

One oddity is that basic image formats like GL_RGBA8 will, when queried with GL_READ_PIXELS, return GL_NO_SUPPORT. This means that it should not be possible to use glReadPixels on FBOs with such formats bound. This seems... unlikely. Especially as I tried it with texture targets GL_TEXTURE_2D and GL_RENDERBUFFER.

Because the operation is unsupported, I also got GL_NONE for GL_READ_PIXEL_FORMAT.

Also, I got GL_NONE for the TEXTURE_IMAGE_FORMAT and GET_TEXTURE_IMAGE_FORMAT. Oddly enough, the _TYPE versions return real values.

tonyo_au
02-09-2013, 10:39 PM
On my 580I get


glGetInternalformativ(GL_TEXTURE_2D,GL_RGBA8,GL_RE AD_PIXELS,1,buffers);

FULL_SUPPORT

glGetInternalformativ(GL_TEXTURE_2D,GL_RGBA8,GL_RE AD_PIXELS_FORMAT,1,buffers);

0x1908

glGetInternalformativ(GL_TEXTURE_2D,GL_RGBA8,GL_TE XTURE_IMAGE_FORMAT,1,buffers);

0x1908



I don't know what 0x1908 is.

Dan Bartlett
02-10-2013, 05:10 AM
0x1908 = GL_RGBA