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Saqib
03-01-2004, 05:41 AM
I've created a 1024x2048 pbuffer and I use it for drawing mulitple stuff to it. Kinda like splitting it up into smaller regions of 640x256 and rendering to them. But when I map these 640x256 areas in the pbuffer onto a quad of the same size ( 640x256 ) i end up getting low quality texture mapping ( jagged edges on polygons etc ) using Linear filtering. Now is there anyway I can fix this without having to increase my drawing areas in the Pbuffer?
Plus is there a way to enable AntiAliasing when using PBuffers, if so how?

Relic
03-01-2004, 09:33 AM
With linear filtering you sample 4 texels. OpenGL texture coordinate clamping does only work on the edges of the full size texture.
To use sub-textures you need to make sure that no texture access goes into the area of an adjacent texture.
This is easiest by using nearest filtering and texture coordinates which are carefully specified to start and end on texel CENTERS!
For linear filtering this needs to be done even more carefully. You either need to pull in your texcoords 1.5 texels or build a border around your sub-textures.
(These can grow big when you try to use mipmapping.)

You figured out p-buffers already, now look for multisampling.