Commit Graph

3 Commits

Author SHA1 Message Date
nmlgc 8b627803a3 [Position independence] Vector calls and variables
Raw, uninteresting position independence work. Or maybe not, given that
this was one of the few things that also apply to TH01, and reveal just
how chaotically this game was coded. And so we've got three ways that
ZUN stored regular 2D points: Regularly (X first, Y second), Y first
and X second, and multiple points stored in a structure of arrays…

Completes P0059, funded by [Anonymous] and -Tom-.
2019-11-18 22:24:24 +01:00
nmlgc a533b5d3ea [Reverse-engineering] [th04/th05] Player sprite area invalidation
And once again, the TH05 version is un-decompilable. :/ It was pretty
close this time, though, as the entire block between PUSH DI and POP DI
kind of resembles a separate inlined function, in accordance with Turbo
C++'s  automatic backup of the DI register, as researched in 7f971a0.

Except that it contains a loop, and Turbo C++ refuses to inline any
function with `do`, `while`, `for`, or `goto`. If it didn't, it would
have totally worked.

Also, yes, C++ class methods are treated identically in this regard.

Oh well. Shot type control functions next, finally!

Completes P0035, funded by zorg.
2019-09-24 22:04:26 +02:00
nmlgc 39c169c30d [Reduction] Separate functions for 1D and 2D vector construction
Look at that TH05 vector2_at_opt function. What the hell, the caller is
supposed to set up the stack frame for the function? How do you even get
a compiler to do this (and no, I haven't found a compiler switch)? No
way around writing a separate "optimizer" as part of the compilation
pipeline, it seems.
2017-01-08 21:01:13 +01:00