Fibonacci Box method for generating Pythagorean triples

Take any two numbers p and q such that p<q to generate the "Fibonacci Box". The construction will generate a Pythagorean triple (a,b,c) and it's associated in- and excircles. If pand q are coprime and not both odd it will generate a primitive Pythagorean triple. For further instructions see article mentioned below.
Price, H. L. (2008). The Pythagorean tree: A new species. ArXiv e-prints, arXiv:0809.4324, p. 14.