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View Full Version : Rectangle Textures MINIMUM size?



charliejay
01-12-2009, 05:51 AM
Hi all,

Do rectangle textures (specifically ARB_texture_rectangle and EXT_texture_rectangle) have a minimum size limit?

I know the minimum POT size is 64, but have been unable to discover if there is a minimum limit for the rectangle extensions.

Cheers, charliejay

Zengar
01-12-2009, 06:20 AM
Minimum size of a texture (any texture) is 1x1. Where did you get 64 for POT from?

charliejay
01-12-2009, 06:40 AM
Got 64 from the GL Red Book. You reckon I should be able to define a base (zero) level 32 x 16 texture, for instance, that isn't a mipmap level, then?

I could have sworn that the Red Book said that the texture dimensions were >required< to be "at least 64", whereas the opengl specs site (specifically http://www.opengl.org/documentation/specs/man_pages/hardcopy/GL/html/gl/teximage2d.html ) certainly says something a little different.

It's not that I'm having trouble with small dimensions for rectangle textures, I just want to know if I can reasonably expect that to be the case on other systems, too...

Brolingstanz
01-12-2009, 06:52 AM
I think 64 is the minimum value for MAX_TEXTURE_SIZE.

It's a minmax sort of thing...

charliejay
01-12-2009, 07:36 AM
I think some testing with POT textures is in order, then. It certainly sounds like small dimensions shouldn't be a problem for rectangle textures, if they aren't for POT textures...

Thanks for the replies, folks.

charliejay
01-13-2009, 01:59 AM
Yeah, did the Red Book a dis-service, there - it says the same thing as the online spec.

Brolingstanz
01-13-2009, 03:42 AM
The GL3 spec ups the minmax to 1024 - same low price.