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debonair
04-03-2013, 12:02 AM
how does GL_TEXTURE_MIN_LOD, GL_TEXTURE_MAX_LOD and LOD_BIAS works?
To check it visually, i have created 6*6 texture wth mipmapping and if for values > 0.5 for MIN_LOD i get a 3*3 texture irespective of values for MAX_LOD. If i change LOD_BIAS it does not affect my o/p. I am not able to figure out how it works exactly.
Can anyone explain it by stating an example.

debonair
04-04-2013, 12:01 AM
Bounce..!!

Dark Photon
04-04-2013, 05:15 AM
Look in the GL 4.3 spec (http://www.opengl.org/registry/doc/glspec43.compatibility.20130214.pdf) and search for "texture min lod". After a few hits you'll end up in Section 8.14 titled Texture Minification.

Look at figures 8.4-8.6 on pgs. 250-251. See subsequent sections such as 8.14.3 Mipmapping for more details. There it takes the computed lamda and maps it to a MIPmap level for different min filters.