..., especially as related to line-drawing accuracy. Particular attention to detail concerning chopping of accumulation errors, using a cast from 64 bit to 32 bit strategy, in the interval [1.0,2.0). Individual pixel errors with overlapping polygons or line segments are about one in a billion, but I can't reproduce any errors at the moment by using random number generation with tens of millions of cases. Emphasis not only on correctness, but also on performance for real-world use or hardware implementation.