In my youth, us Amiga demoscene coders used this method too. You could basically measure CPU consumption by some sub-routine by setting a particular color on en

In my youth, us Amiga demoscene coders used this method too. You could basically measure CPU consumption by some sub-routine by setting a particular color on entry, then resetting on exit. Basically "raster lines" became a measure of time. Pretty sure I optimized by putting a piece of tape at the exit line on the TV, then trying to make the color bar more narrow. :)