A little c++ shader toy that I wrote for rendering a light model. Twenty Spheres This program is based on a classic computer graphics problem.

Yes...15 spheres are shown here!

RPN is a reverse polish command line calculator and repl. It is written in C++ with Lex and Yacc generated grammar. RPN provides a similar syntax as classic reverse polish calculators. I have just released it under the GNU GPLv3 on my github page.