POV-Ray has a powerful set of solid geometry operations and is quite good for generating scene descriptions from another program and then invoking PV to render.
Obviously it's command line rather than a visual tool.
Obviously it's command line rather than a visual tool.
The best use I ever made of it was modeling an addition to my paternal grandparents' barn before they built it. I entered measurements from tape measures and photographs to build up the basic shapes and the addition, before-and-after.
There was something addictive about seeing the final traced image build up line by line. I dissipated a lot of computer-hours in the 1990s with POV-Ray on a 486, then later a Pentium or Power Mac. I even showed my other grandfather how to run it on his FPU-less 68k Mac; now that was slow.