And with all possible .COM executables decompiled, this set of changes
reaches an acceptable scope, allowing us to *finally*…
Part of P0077, funded by Splashman and -Tom-.
And of course, TH05 ruins the consistency once again. Sure, the added
file error handling is nice, but we also have changes in the playful
messages (lol), and now need a third distinct optimization barrier
(🤦)… But as it turns out, inlined calls to empty functions work as
well. They also seem closer to what ZUN might have actually written
there, given that their function body could have been removed by the
preprocessor, similar to the logging functions in the Windows Touhou
games. (With the difference that the latter infamously *aren't*
inlined…)
Part of P0077, funded by Splashman and -Tom-.
Huh, C++ wants its `char`s to be unsigned in order to *not* sign-extend
them to 16 bits for comparison against ASCII literals?!
Anyway, that completes TH03's ZUN.COM, with bascially no new C code.
Part of P0077, funded by Splashman and -Tom-.
The supposedly low-hanging fruit that almost every outside contributor
wanted to grab a lot earlier, but (of course) always just for a single
game… Comprehensively covering all of them has only started to make
sense recently 😛
Also, yes, the variable with the uppercase .CFG filename has itself a
lowercase name and vice versa…
Part of P0077, funded by Splashman and -Tom-.
Oh wow, caff4fe introduced wrong bytes into RES_KSO.COM by confusing
[cfg_bombs] with [credit_lives] -.- Which I didn't find out back then
because all the RES_*.COM binaries still had some different instruction
encodings anyway and I just didn't care enough to base my diff of those
files on the wrong encoding versions to notice the bug…
Whoops.
Part of P0077, funded by Splashman and -Tom-.
4½ years after aa56a7c, it turns out that the correct decompilation
involves… no-ops generated by assigning variables that just happen to
be in registers to themselves?! Which does get optimized out, but only
after TCC folded identical tail code in all branches of a function,
thus effectively functioning as an optimization barrier.
The initial attempt used register pseudovariables, but this definitely
is the best possible way this could work – portable, and doesn't
unnecessarily shred the code into tiny inlined functions pieces. The
mindblowing thing here is that ZUN could have actually written this to
have additional, albeit unnecessary, lines to place breakpoints on. But
that means he must have chosen those two local variables in SI and DI
completely by chance… 🤯
The best thing though? ~#pragma inline is gone~
Part of P0076, funded by [Anonymous] and -Tom-.
Necessary to make string literals from the first one end up at their
correct positions in the data segment even after the upcoming
deduplication…
Part of P0076, funded by [Anonymous] and -Tom-.
Oh hey, guarding declarations with complicated types via #ifdef limits
the header files we additionally have to #include!
Part of P0076, funded by [Anonymous] and -Tom-.
Since they're determined by the order of sprites in a .BFT file,
they're best auto-generated by an enum as much as possible.
Part of P0074, funded by Myles.
Which finally allows us to use the PLANE_SIZE macro in ASM land. Yeah,
(ROW_SIZE * RES_Y) has finally got old.
Part of P0073, funded by [Anonymous] and -Tom-.
Templates would have been nicer, but as soon as you add just one
non-immediate parameter, Turbo C++ generates a useless store to a new
local variable, ruining the generated code.
Part of P0069, funded by [Anonymous] and Yanga.
I did consider not doing this, because "well, can't anyone who's
*actually* interested just diff the TH01 and TH02 implementations to
figure out the differences themselves", but that duplication ended up
feeling too filthy after all.
And hey, it's a nice excuse to update TH02's version to current naming
standards! 😛
Part of P0068, funded by Yanga.
The TH04/TH05 BGM/SE mode setup is a good example for code where
different structure field offsets will vanish completely upon reverse-
engineering. If we continued to use the per-game ID string as the
variable name, we'd only have another game-specific "difference" there.
Part of P0065, funded by Touhou Patch Center.
Funny how the actual scores are stored as little-endian gaiji strings
in the bold font, yet never actually used as such.
Part of P0063, funded by -Tom-.
So many things named `score_*`, so many things named `hiscore_*`…
Let's go with `scoredat_*`, which clearly indicates that this stuff is
saved into a file, while still being only 8 characters.
Part of P0063, funded by -Tom-.
At least wherever Turbo C++ and master.lib want us to use a
non-pointer, since both use uint16_t for segment values throughout
their APIs instead of the more sensible void __seg*. Maybe, integer
arithmetic on segment values was widely considered more important than
dereferencing?
*Finally*. We already used `(unsigned) int` in quite a few places where
we actually want a 16-bit value, which was bound to annoy future port
developers.
Not applying this leak to TH03 since it would have more than one
`key_det` variable, resulting in names that are as much fanfiction as
the current ones…
Yup, function parameters that can clearly be identified as coordinates
are by far the fastest way to raise the calculated position
independence percentage. Kinda makes it sound like useless work, which
I'm only doing because it's dictated by some counting algorithm on a
website, but decompilation will want to un-hex all of these values
anyway. We're merely doing that right now, across all games.
Part of P0058, funded by -Tom-.
That should make this convoluted copypasta a bit easier to read. And
sure, I could have done something about the loop as well, but
SHOT_FUNC_INIT already hides enough control flow behind a macro…
Part of P0037, funded by zorg.
With both 16- and 32-bit build parts soon having full dependency
tracking, having more small includes wins out over having fewer, larger
ones – and also, over having to fix tons of macro conflicts that stem
from most .inc files assuming the context of the big .asm files.
Case in point, including ReC98.inc doesn't work right now without
defining a .MODEL, which is counter-productive for ASM compilation
units.
Part of P0035, funded by zorg.
The TH02 version is a piece of cake…
… but TH04 starts turning it into this un-decompilable piece of
unnecessarily micro-optimized ZUN code. Couldn't have chosen anything
better for the first separate ASM translation unit.
Aside from now having to convert names of exported *variables* to
uppercase for visibility in ASM translation units, the most notable
lesson in this was the one about avoiding fixup overflows. From the
Borland C++ Version 4.0 User's Guide:
"In an assembly language program, a fixup overflow frequently
occurs if you have declared an external variable within a
segment definition, but this variable actually exists in a
different segment."
Can't be restated often enough.
Completes P0032, funded by zorg.
nmlgc