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Apollux
03-31-2003, 03:30 AM
Hi folks!!

I already know that due to some OpenGL tyranny texture igames must come in sizes of 64 (ie. 64, 128, 192*, 256 and so). What I want to know is: Image should be square (ie 64x64) or we can use rectangular images (64x128) ?

I was reading a tutorial on the subject, but written for Maya, and it states that even the fact you can use a 256x128 image, at rendering time that image would take exactly the same amount of memory than a 256x256 image. That holds true for Blender as well?

I remember reading something about OpenGL on Blender doing automatic texture image resizing, is this what it means? (I can't remember where I read that, I guess it was on elysiun)

* Haven't see a 192 image size (64 x 3), but It should be possible.

BgDM
03-31-2003, 01:38 PM
I have used uneven image sizes previously with no problems.

BgDM

harkyman
03-31-2003, 02:16 PM
For rendering you can use an image texture of any size without penalty. If you're making textures for the game engine, though, you'll want to stick to the OpenGL rules, otherwise they'll have to be resized internally and you'll take both a performance and quality hit.

BgDM
03-31-2003, 06:17 PM
Good point harkyman! I was not even thinking of the game engine,(cause I never use it).

BgDM

theeth
04-01-2003, 02:29 AM
don't quote me on this, but I think the best format for openGL texture (hence, gameblender) is square pictures in resolutions that are power of 2 (not multiples of 64), so that would mean (starting from 64)

64 x 64
128 x 128
256 x 256
512 x 512
1042 x 1024
2048 x 2048
and so on

Martin

Apollux
04-01-2003, 04:08 AM
Hummm... don't know if it is true (about the powers of 2), but certanly those resolutions seem VEEEERY familiar to me.

Does anybody have a link to an official OpenGL page speaking on the subject?

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