Tatami (畳) mats have an aspect ratio of 2:1. My works result from diagonally dividing this shape. TG System is a playful generative image-making which limits the main forms but allows all and any variation within them of recursion, proportion and colour. I explore geometry and hence pattern found by mathematical subdivision of simple shapes. The designs form a growing collection of paintings, prints and objects in a range of sizes, styles, forms and finishes.