Commit Graph

12 Commits

Author SHA1 Message Date
nmlgc 0dcd0b8136 [Maintenance] Reimplement TASM's ARG directive for `MOV BX, SP` functions
`cPtrSize` is simply the wrong constant for calculating parameter
offsets on the stack, because it corresponds to the memory model's
default distance, not the function's distance. Luckily, ARG has a
RETURNS clause, and if you declare all parameters in there, ARG won't
emit that pesky and unnecessary `ENTER 0, 0` instruction. Big discovery
right there!
Sadly, ARG is unusable for ZUN's silly functions that keep the base
pointer in BX. TASM declares the resulting equates as `[BP+offset]`,
and it's apparently impossible to only get `offset` out of such an
equate later.

So, rather than staying with numbers, let's reimplement ARG for these
functions instead. This way, we can even abstract away the stack clear
size for the `RET` instructions.
It's a bit rough around the edges though, forcing you to explicitly
specify the function distance, and to pass the parameters in reverse
order compared to the C declaration (thankfully, all of these use the
PASCAL calling convention). It also doesn't work with more complex
types yet. But certainly better than numbers.

Part of P0134, funded by [Anonymous].
2021-02-20 23:50:00 +01:00
nmlgc 164591f9fe [Maintenance] Consistently express angle literals in signed hex format
Originally just a workaround to remove angles from the PI counter, but
having the sign indicate the Y direction also makes them a lot nicer to
read in C land.

(Maintenance mode commit)
2020-10-02 14:48:54 +02:00
nmlgc a417b01634 [Reverse-engineering] [th04] Player shots: Option laser blitting
Used for Marisa's shot in TH04, but still present in TH05, so it makes
sense to cover it now.

Part of P0118, funded by -Tom- and Ember2528.
2020-09-17 22:25:11 +02:00
nmlgc fb67d4d054 [Maintenance] Rename all old *_X and *_Y constants to *_LEFT and *_TOP
Part of P0112, funded by [Anonymous] and Blue Bolt.
2020-08-28 15:14:22 +02:00
nmlgc 5d76fd6f64 [Reverse-engineering] [th04] Bombs: Star animation structure
The trivial one first, while I try to wrap my head around what's going
on with Reimu's TH05 bomb animation…

Part of P0111, funded by [Anonymous] and Blue Bolt.
2020-08-28 15:04:39 +02:00
nmlgc c5b5dc0201 [Reverse-engineering] General bomb-related globals
Yup, function pointers, frame counters, and general state variables for
all 5 games.

Part of P0111, funded by [Anonymous] and Blue Bolt.
2020-08-28 15:03:03 +02:00
nmlgc 60a700eeda [Maintenance] Declare the "no valid point" constant (-999) in a single place
Part of P0110, funded by [Anonymous] and Blue Bolt.
2020-08-19 19:32:37 +02:00
nmlgc 8af732a6a5 [Reverse-engineering] [th04/th05] Player shot hitboxes
As in, the global variables describing the area that should be checked
for collisions with player shots in the next call to the shot hit test
function.

Part of P0109, funded by [Anonymous] and Blue Bolt.
2020-08-16 21:40:34 +02:00
nmlgc 70b4134af4 [Maintenance] [th04/th05] Assemble 16-bit .ASM files case-sensitively
Otherwise, TASM would simply convert all EXTRN declarations in those
files to uppercase. Then, the linker would expect them in uppercase,
forcing both the case-sensitive big 32-bit .ASM files *and* the entire
C land to declare them as uppercase as well.

For functions with __pascal convention which are always uppercased
anyway, this makes no difference. It does matter for regular __cdecl
variables, though, and the C declaration of [score_delta] in e6294c2
already showed that we'd then be forced to use macros if we wanted to
pretend that these names still had lowercase characters.

Doing this for every variable referenced in both C land and 16-bit ASM
land gets annoying quickly. So, no need to force this inconsistency if
we can get rid of it by slightly uglifying ASM land.

Part of P0089, funded by [Anonymous] and Blue Bolt.
2020-05-03 23:56:08 +02:00
nmlgc bf40b4e375 [Maintenance] [th04/th05] Declare GRCG register setting functions in C land
Part of P0089, funded by [Anonymous] and Blue Bolt.
2020-05-03 23:38:32 +02:00
nmlgc ba66fcc801 [Reverse-engineering] [th04/th05] Currently alive player shots
Copying out the shot position might have actually been a decent
optimization for hit detection, to avoid the indirection if the shot
is not colliding with anything.

Part of P0088, funded by -Tom-.
2020-05-03 23:18:56 +02:00
nmlgc d1f3dcd620 [Maintenance] Move all features exclusive to MAIN.EXE to a main/ subdirectory
Adding op/, main/, and end/ directories does nicely cover a great
majority of the "not really further classifiable slices" implied in
d56bd45.

Part of P0086, funded by [Anonymous] and Blue Bolt.
2020-04-15 20:58:01 +02:00