/vr/ - Retro Games

Sprite design has been documented, though.
https://desuarchive.org/vr/thread/5163337/

Computers from the old days were designed in such a way that they were de facto intended for people who were knowledgeable about programming and mathematics. You could draw with a computer, but saving what was displayed on the screen wasn’t without its problems, hence the fact that the Japanese industry would start to use graphic editors only years later.
The people in charge of graphic design in those days needed 3 things: grid paper, a computer with a keyboard and basic knowledge of hexadecimal. Michitaka Tsuruta, who studied animation in school and later designed Solomon’s Key, joined Tehkan in 1982 and used that system in the early years of his career: “You would color in the squares on graph paper. And then after you coloured those individual squares, you would convert them in to numbers, and then you would key in the numbers in hexadecimal using a ROM writer”.
It’s only after passing these steps that the designer could see his work displayed on the screen and sometimes feel the need to reiterate the whole process in case of mistake or unsatisfying rendering.
Using the hexadecimal system contributed to save ROM space by minimizing the size of the graphical data at a time when it was very expensive. Although many graphic designers have fond memories of the 2D era, few of them seem to regret the transition to a more direct approach: “I was the main background designer for T.A.N.K (SNK, 1985), recalls Toshiyuki Nakai. We also started using specialized graphic tools at this time: no more drawing on graph paper! Now you sat at a monitor and used a keyboard to change colors and so forth. Again, it’s very close to how we do things today. I can still remember what a relief it was switching to those new systems… it was so much easier than before!”