/vr/ - Retro Games

>>7780975
Slowdown is pretty rare on C64 games but then it seemed programmers normally tried to avoid code loops that would overflow the raster time and take multiple frames, while NES programmers much of the time seemed to not give a shit and just accepted some slowdown as the price to pay.

A big issue with many C64 games is the h/w scrolling is extremely greedy and takes up to 20% of the CPU. NES scrolling takes like 2%. Note that VSP scrolling solves this issue nicely and saves a lot of cycles, unfortunately it wasn't discovered until 1992 or something and some C64s choke on it. however most modern homebrews use VSP because it's so much more efficient.

Setting up the color RAM carefully also saves CPU time while scrolling; ideally you want to design your graphics so the color RAM doesn't have to be touched at all. for example the "action" sections in North & South are set up like this. the lower part of the screen uses all yellow and the upper part white for the set colors so it doesn't have to scroll or touch the color RAM.