Thanks to help from John Tsiombikas who was able to

verify that the FreeGLUT and GLUT torus routines

do generated the same size objects, I took a look at

the code in the FreeGLUT sources. By comparing

that with the parametric form for the surface of a

torus:

http://en.wikipedia.org/wiki/Torus

It is clear that the parametrization there

with:

R is the distance from the center of the tube to the center of the torus,

r is the radius of the tube.

so it is clear that R corresponds to the "outer radius"

of the torus and that r corresponds to the "inner radius"

of the torus. The bug was one of comprehension and

poor documentation. It would be helpful to add the

above text describing what the two parameters are...