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PrestoChung
04-28-2011, 08:21 AM
I read in the manpages
"GL_NUM_COMPRESSED_TEXTURE_FORMATS
params returns a single integer value indicating the number of available compressed texture formats. The minimum value is 4."

When I query with glGetIntegerv it returns 3.

arekkusu
04-28-2011, 08:39 AM
The man page is wrong.

It's assuming that the RGTC formats promoted to the core should be exported.
But they shouldn't be, per ARB_texture_compression_rgtc Issue 19.

This query is essentially useless. If you want to know what formats are supported you should look at the core version and extensions.

PrestoChung
04-28-2011, 08:49 AM
I suppose that's why the first 'format' it returns equals 0x83F0 which is not defined as anything in my gl3.h file?

arekkusu
04-28-2011, 09:00 AM
0x83F0 = GL_COMPRESSED_RGB_S3TC_DXT1_EXT, per EXT_texture_compression_s3tc.

This format that is (almost) universally supported isn't promoted into the core, so it's not in gl3.h.

PrestoChung
04-28-2011, 09:17 AM
Thanks for the quick reply :D

PrestoChung
04-29-2011, 08:04 AM
Edit: Mis-spelling in the man pages threw me off on this one. The have GL_DRAW_FRAMEBFUFER_BINDING instead of FRAMEBUFFER :eek:

PrestoChung
04-29-2011, 10:42 AM
Here's a new one. These are in gl3.h but querying with GetIntegerv leaves my GLint unchanged:

glGetIntegerv( GL_MAX_VERTEX_STREAMS, lint );
glGetIntegerv( GL_MAX_TRANSFORM_FEEDBACK_BUFFERS, lint );