rgl: ellipse3d with axes

The normals component contains the surface normals.  It is used to 
help in rendering the surface, but isn't much use for your purposes.
Unfortunately, I'm not familiar enough with the internals of princomp 
to tell you how to get the axes you want.

Duncan Murdoch

OK, then let me repharase it. The axes of the unit  sphere are like

axes <- matrix(
    c(0, 0, -1,   0, 0, 1,
       0, -1, 0,   0, 1,  0,
       -1, 0, 0,   1, 0, 0),  6, 3, byrow=TRUE)
taken in pairs.  I'd like to transform these coordinates the same was as 
in ellipse3d() and add them to the plot.

Michael Friendly     Email: friendly AT yorku DOT ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
Toronto, ONT  M3J 1P3 CANADA