In which ZUN needs a hack to make columns of vertical bumper bars work
at all with the way the Orb's X velocity is implemented… and may have
just deliberately ensured that the Orb can definitely loop infinitely
between two bumpers.
(Those two wrong NOPCALLs aren't worth working around. It would
basically require taking apart the entire function, and they'll be gone
by the next two commits anyway.)
Part of P0203, funded by [Anonymous] and GhostRiderCog.
Common sense: Entity backgrounds always go into slot X, missile sprites
into slot Y, and wave sprites into slot Z
ZUN: "Nah, let's set aside two slots, and bosses can just freely use
them as they want 🎺"
Part of P0165, funded by Ember2528.
There's a reason why the game reserves memory for exactly this many,
after all. This way, we also stop pretending that the game's use of
.PTN is neatly decoupled from the format's interface…
Part of P0165, funded by Ember2528.
Hooray, separate sprites for facing left and right. That huge function
would have probably been less than half as long if ZUN just implemented
sprite mirroring, but doing that on PC-98 might have been just a
little bit *too* nontrivial for a first game. (At least he did it in
TH03, where he couldn't get away with pre-mirrored sprites.)
Part of P0162, funded by Ember2528.