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View Full Version : PBO and mipmap



speedy gonzalez
11-25-2004, 07:35 AM
Hello, I have an application which calls glTexSubImage2D at everyframe to do texture streaming (video).

I was about to use PBO to speed it up but I just realized that the application also calls glTexSubImage2D for every level of the mipmap stuff.

So I was wondering: should I create N separate PBO one for each level or should I create one big PBO and use offseting to fill the levels ?

Note: I've read somewhere that mipmap allocates 1/3 more memory than without mipmap so that is what I would pass to glBufferData.

I also notice that GL_SGIS_generate_mipmap extension is supported on my machine so I might use that instead. Any recommendation not to ?

ZbuffeR
11-25-2004, 01:55 PM
>> GL_SGIS_generate_mipmap extension is supported on my machine so I might use that instead. Any recommendation not to ?
none, unless the mipmap levels are precomputed in your video or you have a special way to create mipmaps.
You probably won't beat the hardware speed to do that.