Squeezing Onto A Real Screen

Coaxing a program into working order in a TRS-80 Model 100 emulator that could display one slice of an antique cross-platform image file on the screen of that just as antique portable computer had been just the sort of small accomplishment, kind of pointless now yet “once it would have been amazing,” that keeps me delving into “old computers.” Writing up a post about that for the sake of keeping this journal updated every so often, though, did raise a thought or two about whether I’d somehow discharged my motivating energy and would drift along to something else. There was space left for improvement to the program to be sure. Even if rewriting it in anything faster than BASIC remains a towering challenge for me, I could do something about it being “basic.” While I’d got started just by seeing what sort of image could be evoked in the limited number of pixels on a Model 100’s screen, deciding to “work with tools at hand” as much as not bothering to “reinvent the wheel” and padding that image out to the fixed dimensions of an RLE file (which had once seemed a “lowest common denominator” of its day, but had just happened to also be the maximum resolution of my family’s desktop home computer back then) had got me wondering about starting somewhere else than the top left-hand corner and showing a different slice of any one of the RLE images I’ve collected.
( Development at length, with pictures and programs at the end )