Raytracing with MySQL

Raytracing is a method for drawing scenes by modeling beams of light, illuminating and richocheting off objects. It's realistic but very slow, and only the newest and most expensive video cards [Amazon] introduce it to realtime games. MySQL is the most commonplace relational database, the sewer containing all the web's fatbergs, the last thing on earth you'd use for number-crunching graphics. Or ... is it? Behold the MySQL Raytracer, by Holtsetio.

This is a raytracing engine contained in a single Mysql SELECT statement. In the beginning of the code there are a few parameters that can be modified. The scene can be specified using the @triangles and @squares parameters, but everything is explained in the comments. The whole query returns a bitmap file which can be written to the filesystem using the "INTO DUMPFILE" syntax at the end of the query, if mysql has filesystem write permissions.
The raytracer supports shadows and reflections, which makes it, to my knowledge, the most advanced MySQL raytracer on the market right now. However, it is not really polished and kinda slow. Since I didn't really know how to present this work in a demoparty friendly way, I just included two finished renderings.