BRL-CAD is a powerful cross-platform open source solid modeling system that 
includes interactive geometry editing, high-performance ray-tracing for 
rendering and geometric analysis, image and signal-processing tools, a 
system performance analysis benchmark suite, libraries for robust geometric 
representation, with more than 20 years of active development.

NOTE: This package needs about 3.1GB of space to build, so adapt your OUTPUT / 
TMP variables if necessary.