Some of the unused interleave masks are not that straightforward, so it
makes sense to have all of them as a bitmap. I'm positive that this
sort of thing could have been EGC-accelerated… although, simply
writing better C would probably already go a long way.
Part of P0121, funded by Yanga.
Well well, the choice between sorting this function mechanically (and
putting it next to the EGC functions) or contextually (and putting it
next to the GDC SCROLL function)… Any choice would eventually turned
out suboptimal, I'm sure. 😅
Part of P0121, funded by Yanga.
Surprise, it's the (terribly suboptimal) setgsta() example function
from the PC-9801 Programmers' Bible! 100% identical, so ZUN must have
read that book as well.
Used for screen shaking effects, as well as the scrolling backgrounds
at the start of the Final Boss stages.
Completes P0095, funded by Yanga.
nmlgc