The Melee
The Rithmatist is a book by best selling author Brandon Sanderson in 2013. It includes a facinating magic based magic system. The Melee is a project to create a version fo this magic system in Vertual Reality.
The magic system is based on drawing geomentric diagrams on the ground in chalk. There are four main types of lines: Lines of Forbidance (whitch take the form of streight lines), Lines of Warding (circles or ovals), Lines of Vigor (sine waves), and Lines of Making (drawings of creatures).
This site is a repository for articles disgue the mechanics and mathmatical ideas around creating a VR game our of Rithmatics.