Geomview

[mbp]

Geomview uses Mark Overmars' FORMS library, which in turn uses the
SGI font manager library  (fmsetfont(), fmscalefont(), fmprstr(), etc.).
The last we'd heard of RS/6000 GL, it didn't have anything like this,
but that was a while ago; does it now?  Aside from that, there's a fair
chance it could be ported without too much difficulty.

Barring a usable font manager, it might be possible to have a
stripped-down version of geomview with graphics windows but no FORMS
control panels.  For anything more ambitious, you might have to do the work
yourself.  Are any of these possibilities appealing?