🚀 go-pugleaf

I have also been very pleased with tracer, and have displayed several
pictures on an Apple Laserwriter.  They look even better with some
simple anti-aliasing!

However, does anyone know what causes the glitches in the image of the floor?
I find that the 12th and 13th horizontal (across the picture) lines
(counting from the 1st, at the front) are missing, and some lines appear
to be added further back (just before lines away from the view point,
are lost in the aliasing noise). I've looked at the source, and can't see
anything wrong, so suspect some sort of rounding error, or that it
is just another form of aliasing.

PS
	Has anyone else paused to wonder how many machine instructions
have been executed (worldwide) to execute this program?

PPS
	The PS is rhetorical!