LuaCAD models solids in Lua rather than the OpenSCAD language, with operator overloading for CSG (`a + b`, `a - b`, `a * b`). It ships with a CLI and a desktop app, including a preview area and a text editor. I've always been a big fan of OpenSCAD, but the SCAD language itself is unfortunately quite cobbled-together and is a very poorly designed programming language. LuaCAD takes all the good parts of OpenSCAD and combines them with one of the best scripting languages. It has now completely repl...