Hi Peter, Gluperspective should give you the same results as a Frustum call. I have tested it previously.
If your Gluperspective is unprototyped then it won't work. The params will be treated as floats.
void gluPerspective( GLdouble fovy,
GLdouble aspect,
GLdouble zNear,
GLdouble zFar);
Solution: Create a temp prototype mapped to GluPerspective.
! gp (double f,a,zn,zf) at Gluperspective
gp 45.0, aspect, 0.1, 100.0