[osg-users] Mip Maps

[David Heitbrink]

I having an issue with rendering models with mip maps, when I render my scene I get some strange aliasing on text in the texture.

I am mostly using DDS files, some texture have mip maps, some do not. If they do not have a mip map defined I am setting: 

texture->allocateMipmapLevels();


So to test this I added some test code to my shaders to manualy cycle through the mip map levels (FrameNum is a uniform that is incremented every frame):

Code:

vec4 texel = texture2D(TextureId,TexCoord[0]);
int txtLvl = textureQueryLevels(TextureId);
int lvl ;
if (txtLvl > 1){
    lvl = (FrameNum/10) % txtLvl;
    texel = textureLod(TextureId,TexCoord[0],float(lvl));
    if (lvl == 0 ) texel.r+=0.5;
} 




In most of my scene I am getting the red flashing every couple of seconds or so. But the texture does not blur out. In a handful of cases I have some textures that do blur out, but most do not. 

Does any one have any ideas on what could be causing this issue?

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http://forum.openscenegraph.org/viewtopic.php?p=69997#69997