working on getting 40x192 cycle-counted mode.  you have to self-modify
screen contents mid-screen so you ounly get about 12 or so blocks
across in this mode

really cool rasterbar effect

attempted to get cycle-counted pt3 player going, wasted a lot of time
on that, didn't get it working in the end

these proofs of concept were used in the Demosplash 2019 lores-escape demo
