quad:Disk(inner, outer, slices, loops)
inner is 0, then no hole is generated. The disk is subdivided around the z axis
into slices (like pizza slices) and also about the z axis into rings (as specified by slices and loops, respectively).
With respect to orientation, the +z side of the disk is considered to be "outside" (See quad:Orientation for details.).
This means that if the orientation is set to #GLU_OUTSIDE, then any normals generated point along the +z axis. Otherwise,
they point along the -z axis.
If texturing has been turned on (with quad:Texture()), texture coordinates are generated linearly such that where r = outer , the value at (r, 0, 0) is (1, 0.5), at (0, r, 0) it is (0.5, 1), at (-r, 0, 0) it is (0, 0.5), and at (0, -r, 0) it is (0.5, 0).
Please consult an OpenGL reference manual for more information.