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View Full Version : mipmapping and BASE_LOD



zen
03-14-2002, 03:42 PM
I get the following strange(?) behaviour:I create a texture set min and mag filter to LINEAR_MIPMAP_LINEAR and LINEAR and also BASE_LOD and MAX_LOD to some values.THen I call gluBuild2DMipmaps to create the mipmaps.Code follows:



/*create the texture*/
glBindTexture(GL_TEXTURE_2D,i);
/*initialize texture*/
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTE R,minf);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTE R,magf);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_BASE_LEVE L,baselevel);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAX_LEVEL ,maxlevel);

gluBuild2DMipmaps(GL_TEXTURE_2D,intern,w,h,format, GL_UNSIGNED_BYTE,pixels);


Now when baselevel is anything greater than 0 the texture looks distorted(that is it just bares some resemblance to the initial texture).Setting maxlevel works fine though.Also if I use a mipmap generator of my own and just create and load all mipmaps between baselevel and maxlevel I get an error from the driver saying it failed to upload the texture and level 0 of the texture is some sort of a tiled MESA logo.The other level(s) are distorted as with gluBuild2DMipmaps.Is this normal or a driver bug?According to the specs I only need to upload levels baselevel to maxlevel to get a mipmap complete texture.