TessMark is an OpenGL benchmark and tech demo that uses the new hardware tessellation (or GPU tessellation) features exposed by the OpenGL 4 API and available on the latest graphics cards like the NVIDIA GeForce GTX 480 or the ATI Radeon HD 5870. Hardware tessellation makes it possible to divide a polygon into smaller ones (according to the tessellation level factor) in order to increase polygons density: the higher the tessellation level, the higher the polygon density. A high tessellation level requires much GPU processing power.