I have a texture drawn in a quad. The texture has mimaps attached to it. I access the texture the usual way, with
Code :
texture(sampler, coord);
According to the specification, A third argument can be used for LOD (level of detail). But when I try that, I get no visible effect, no matter what value I try.

There is also the textureLod() function, which takes LOD as argument. This gives the same result. I don't understand the difference between texture() and textureLod(). Shouldn't a specified LOD give a picture with lower resolution?

To make certain there there really are mipmaps defined, I verified it by doing a glGetTexLevelParameter() for GL_TEXTURE_WIDTH on various levels. What I am really looking for, is a way to downsample a bitmap.