This fixes a bug where the player could bring up the map on the very
first frame of a gamemode(game) animation. This is because the menu
animation checked graphics.menuoffset, but graphics.menuoffset wouldn't
have changed at that point because it only set graphics.resumegamemode.
Instead, just check for graphics.resumegamemode directly. We also need
to assign it to false whenever the map is closed so the player won't be
prevented from using the map screen again.
This fixes all the headaches about map.extrarow having to be the correct
value and which way it should be and whatnot. The latest headache was
the detection that prevent user-initiated menu animations while an
animation was already happening being tripped because
graphics.menuoffset would be 230 (due to closing the menu while being in
a room without a room name), but then going to a room with a room name
would check for 240 instead, and 230 is less than 240. (The numbers are
the wrong way round because I got the ternaries the wrong way round, but
even if the numbers are the correct way round, the bug would still
happen, but it would just be reversed.)
So instead, I've just made it 240 for both. This doesn't change the
duration of the menu animation (because the animation moves in
increments of 25, and 230 / 25 == 240 / 25 under integer division). It
might change the animation slightly, but it was already inconsistent
anyway because map.extrarow was always set to be 1 in custom levels, and
I legitimately would not be able to tell the difference without
recording the animations and nitpicking it frame-by-frame.
Fixes#841.
The player gets kicked out of the Super Gravitron if they have
invincibility or slowdown enabled. However, this can be confusing if no
message pops up
( https://steamcommunity.com/app/70300/discussions/0/3039355280230178910/ )
. So I've made it so that a text box will pop up when they get kicked
out.
This makes it so gamemode(teleporter) will always do an animation, even
if the game is already in TELEPORTERMODE.
I used this script to test:
gamemode(teleporter)
delay(5)
gamemode(teleporter)
delay(5)
gamemode(teleporter)
In 2.2, this script starts the map menu bringing-up animation three
times.
In previous 2.3, this script starts the map menu bringing-up animation
once, but then the next gamemode(teleporter) immediately finishes the
animation, and the third gamemode(teleporter) does nothing.
This commit restores it to 2.2 behavior.
This makes it so it's not even possible to stay on the TELEPORTERMODE
screen by opening the map while it's being brought down. It also makes
it so the map animation is able to be canceled when being brought up
just by opening the map and closing it.
Fixes#833.
This restores it to 2.2 behavior, where the cutscene bars timer also
ticked in TELEPORTERMODE. It was a 2.3 regression that the cutscene bars
timer didn't tick there.
This makes it so if you manage to get stuck in TELEPORTERMODE when a
cutscene ends, the cutscene won't be stuck on untilbars() waiting for
the cutscene bars to go away, since the cutscene bars timer now ticks.
Also, add a sync parameter to avoid calling syncfs too often.
Calling syncfs twice in a row is both inefficient and leads to errors
displaying twice. This allows us to bypass it when saving unlock.vvv as
part of savestatsandsettings.
This object basically had no reason to exist... it was just more verbose
to use, which really reminded me of Java. Anyway, this is the last thing
named after the editor for no reason when it should be a part of the
customlevelclass, so I moved its attributes to customlevelclass.
This fixes the fact that the name of the singular type is plural, but
the name of the plural array is singular. Which has always annoyed me,
too. Also this makes it more clear that custom entities don't have much
to do with the editor.
That's what it is - it's an entity in a custom level. Not something to
do with the editor, necessarily. Like before, the name of the XML
element will remain the same.
That's what edlevelclass is... so that's what it should be named. (Also
removes that "ed", too, making this less coupled to the in-game editor.)
Unfortunately, for compatibility reasons, the name of the XML element
will still remain the same.
CustomLevels.h now uses 4-space indents - like all other space-indented
files - instead of 2-space indents. This has bugged me for a while and I
decided to just fix it now.
This is a pretty hefty commit! But essentially, I made a new editorclass
object, and moved all functions and variables that only get used in the
in-game level editor to that class. This cleanly demarcates which things
are in the editor and which things are just general custom level stuff.
Then I fixed up all the callers. I also fixed up some NO_CUSTOM_LEVELS
and NO_EDITOR ifdefs, too, in several places.
As far as I can tell, this function has never been implemented, and only
existed in this header file. FILESYSTEM_getLevelDirFileNames() already
exists (well, used to exist; it's been changed and renamed to
FILESYSTEM_enumerateLevelDirFileNames()), so I'm removing this now.
This accompanies the editor.cpp -> CustomLevels.cpp change; I'll be
splitting out the editor functions in the next commit. The name of the
include guard has been changed as well, but not anything else.
This moves editorrenderfixed(), editorrender(), editorinput(),
editorlogic(), and their associated functions to a new file named
Editor.cpp - which is exactly what it says on the tin; it stores all the
functions related to the actual in-game editor loop. Also, the existing
editor.cpp has been renamed to CustomLevels.cpp.
All XML functions now check the return value of
tinyxml2::XMLDocument::Error() after each document gets loaded in to
TinyXML-2. If there's an error, then all functions return. This isn't
strictly necessary, but printing the error message that TinyXML-2 is the
bare minimum we could do to be useful.
Additionally, I've standardized the error messages of missing or
corrupted XML files.
Also, the way the game went about making the XML handles was... a bit
roundabout. There were two XML handles, one for the document and one for
the root element - although only one XML handle suffices. So I've
cleaned that up too.
I could've gone further and added error checking for a whole bunch of
things (e.g. missing elements, missing attributes), but this is good
enough.
Also, if unlock.vvv or settings.vvv don't exist yet, the game is
guaranteed to no-op instead of continuing with the function. Nothing bad
seems to happen if the function continues, but the return statements
should be there anyway to clearly indicate intent.
If settings.vvv doesn't exist, loadsettings() calls savesettings(), but
savesettings() already prints a message if settings.vvv doesn't exist.
So then the output would look like
No settings.vvv found. Creating new file
No settings.vvv found
Which is clearly redundant.
The same thing happens with unlock.vvv, but in that case the following
prints instead
No unlock.vvv found. Creating new file
No Stats found. Assuming a new player
I will need to be able to return from this function if there's an XML
error, otherwise writing out the control flow manually gets really
nasty. And while I'm at it, it's some a nice de-duplication as well.
To do this, we create a temporary struct that bundles up all the
information we want for the summary, and pass it in to the intermediate
load function.
Furthermore, we can get rid of reading map.finalstretch - it affects
nothing. map.finalmode is still needed, however, because of the usage of
map.area().
Previously, Flip Mode rendering had to be complicated and allocate
another buffer to call FlipSurfaceVerticle, and it was just a mess.
Instead, why not just do SDL_RenderCopyEx, and let SDL flip the screen
for us? This ends up pretty massively simplifying the rendering code.
`-forcecolor` will force color to be on. `-nocolor` will force color to
be off.
And just because I'm a nice person, I've also added British versions of
those flags. As a treat.
This includes the bold as well.
INFO is just default, WARN is yellow, ERROR is red.
We try to automatically detect if the output is a TTY (and thus supports
colors), and don't emit colors if so. Windows 10 supports ANSI color
codes starting with a specific build, but we don't care to emit whatever
garbage Microsoft invented for builds older than that.
This is because the y-position of the graphics.onscreen() check was a
little too high. Then their name (under Beta Testing) would suddenly
disappear too early. You'd have to look real close to spot it, but it
does happen. It's cuz the credits are all kinda hardcoded, which is
probably bad, but fixing that would have to come later...
I talked with Ethan earlier about this. For 2.3, he wanted me in GitHub
contributors (well, still separate from the rest), to really highlight
the source-code-release community-driven nature of 2.3, but he said it'd
be fine to put me in C++ credits in 2.4.
The game will freeze the player immediately if they release a
directional button within 3 frames of pressing it. Similar to flipping,
this involves global state, and will only apply to the first player
entity.
Closes#484
Flipping only applies momentum to the player entity currently being
processed. This normally wouldn't be a problem. However, flipping
involves global state, and only one flip can occur per frame. This means
that additional player entities don't get this boost of momentum, which
feels somewhat unnatural during gameplay.
This commit fixes this by splitting flip logic out of the loop over
player entities, and applying the flip momentum to all player entities.
We need to check for graphics.setflipmode, not graphics.flipmode,
because graphics.flipmode only gets assigned at the end of the frame
(due to the deferred callback). Otherwise, returning from the options
menu would always turn flag 73 on, which would make you ineligible to
get the Flip Mode trophy, even if you're in Flip Mode.
Originally this started as a "deduplicate a bunch of duplicated code in script commands" PR,
but as I was working on that, I discovered there's a lot more that needs to be done than
just deduplication.
Anything which needs a crewmate entity now calls `getcrewmanfromname(name)`, and anything which
just needs the crewmate's color calls `getcolorfromname(name)`. This was done to make sure that
everything works consistently and no copy/pasting is required. Next is the fallback; instead of
giving up and doing various things when it can't find a specific color, it now attempts to treat
the color name as an ID, and if it can't then it returns -1, where each individual command handles
that return value. This means we can keep around AEM -- a bug used in custom levels -- by not
doing anything with the return value if it's -1.
Also, for some reason, there were two `crewcolour` functions, so I stripped out the one in
entityclass and left (and modified) the one in the graphics class, since the graphics class also
has the `crewcolourreal` function.
If `setactivitytext` was the last line in a script,
the command would index the vector out of bounds.
I also modified the formatting to keep consistent
with the rest of the codebase.
These commands will change the colour and text of the next
activity zone that gets spawned. `setactivitycolour` takes all
textbox colors, and `setactivitytext` will take the text on
the next line. These commands were designed this way
to avoid breaking forwards compatibility.
When an activity zone is spawned through the
use of `createactivityzone`, and `i` is 35,
then it'll change the activity zone text to
"Press ENTER to interact".
On Emscripten, SDL_Delay is implemented as a busy loop. In addition,
everything happens on a single thread. This effectively means that
you have to let Emscripten manage the main loop, since if you do it
yourself the browser will just be frozen.
Otherwise, the new arguments to destroy(), which are 'moving' and
'disappear', would be thrown away by the simplified parser. Let's create
less work for ourselves to do and simply not have a hardcoded list of
allowed arguments for destroy() in the parser.
destroy(platforms) has been bugged since 2.0. The problem with it is
that it removes the platform entity, but doesn't remove its block. This
results in essentially turning the platorm invisible and stopping it
from moving.
This error should be fixed, but some levels (including my own) rely on
the invisible platform trick. So instead, the fixed version will be
implemented under a different name, destroy(moving).
There's also another problem with destroy(platforms), which is that the
name is misleading and it doesn't additionally destroy disappearing
platforms. I would also fix this, but in order to not run the risk of
breakage, it will have to be implemented under a different name, too. So
this will be destroy(disappear). As an added benefit, it's also more
granular to have platform-destroying functions under different names
than it is to consolidate them under the same name.
When I added the two-frame delay fix, I didn't realize that Game had a
roomchange variable that was being used as a temporary variable here.
Now that it's fully spelled out and obvious (just look at the top of
gamelogic()), I realize that the variable exists and is being used, and
other readers will realize it's being used too - so now that I know it
exists, I can axe the screen_transition variable I added in favor of
using roomchange instead.
The purpose of this variable was to keep track of if gamelogic() called
map.gotoroom() at any point during its execution. So map.gotoroom()
always unconditionally set it to true, and then gamelogic() would check
it later.
Well, there's no need to put that in a global variable and do it like
that! It makes it less clear when you do that.
So what I've done instead is made a temporary macro wrapper around
map.gotoroom() that also sets roomchange to true. I've also made it so
any attempt to use map.gotoroom() directly results in failure (and since
then using map.gotoroom() in the wrapper macro would also fail, I've had
to make a gotoroom wrapper function around map.gotoroom() so the wrapper
macro itself doesn't fail).
This is a temporary vector that only gets used in mapclass::gotoroom().
It's always guaranteed to be cleared, so it's safe to move it off.
I'm fine with using references here because, like, it's a C++ STL vector
anyway - when we switch away from the STL (which is a precondition for
moving to C), we'll be passing around raw pointers here instead, and
won't be using references here anyway.
This is a temporary variable that doesn't need to be on Game. It is
guaranteed to be initialized every time mapclass::gotoroom() gets
called, so it's safe to move it off.
Enemy/platform bounds are intended to not be drawn if they cover the
whole screen, since that's what their default bounds are.
However, the code inadvertently made it so if ANY of the bounds touched
a screen edge, the bounds wouldn't be drawn. This is because the
conditionals used "and"s instead of "or"s. The proper way to write the
positive conditional is "x1 is 0 and y1 is 0 and x2 is 320 and y2 is
240", and when you invert that conditional, you need to also invert all
"and"s to be "or"s. This is not the first time that the game developers
failed to properly negate conjunctional statements...
This is to make it so RNG is deterministic when played back with the
same inputs in a libTAS movie even if screen effects or backgrounds are
disabled.
That way, Gravitron RNG is on its own system (seeded in hardreset()),
separate from the constant fRandom() calls that go to visual systems and
don't do anything of actual consequence.
The seed is based off of SDL_GetTicks(), so RTA runners don't get the
same Gravitron RNG every time. This also paves the way for a future
in-built input-based recording system, which now only has to save the
seed for a given recording in order for it to play back
deterministically.
Otherwise, levels could leave stale arguments in the array, and then the
behavior of another level loaded right after might end up being
different because of that.
This is done for consistency with Terry's patrons, which are sorted by
first name and not last.
Also some people go with their usernames and so don't have a last name
to speak of, which ended up being pretty weird.
Kai is my last name. Elizabeth is my middle name. I went with my middle
name as last name for a while before figuring out what I wanted my last
name to be.
Third time's the charm.
The fundamental problem with the previous attempts was that they ended
up saying arguments existed due to stale `words` anyway. So to actually
know if an argument exists or not, we need to assign to `argexists` _as_
we parse the line.
And make sure to take care of that last argument too.
Also I thoroughly tested this this time around. I'm done pulling my hair
out over this.
Ever since tilesheets got expanded, custom levels could use as many
tiles as they wanted, as long as it fit under the 32-bit signed integer
limit.
Until 6c85fae339 happened and they were
reduced to 32,767 tiles.
So I'm being generous again and changing the type of the contents array
(in mapclass and editorclass) back to int. This won't affect the
existing tilemaps of the main game, they'll still stay short arrays. But
it means level makers can use 2 billion tiles once again.
This lets users place down tiles above 1199 in Direct Mode, if their
tilesheet has more than 1200 tiles.
I don't like the copy-pasted code here but it'll have to make do.
If you use Lab tilecol 6, you get the rainbow background. However, this
is unintended, because the associated autotiling is... not very good.
To combat that, Ved disallows using the Lab rainbow background outside
of Direct Mode. We will follow Ved here and only allow switching to the
rainbow background if you're in Direct Mode. Also make sure if someone
is disabling Direct Mode with the rainbow background that it gets reset
properly.
The main game used a set of copy-pasted code to set the music of each
area. There WAS some redundancy built-in, but only three rooms in each
direction from the entrance of a zone.
Given this, it's completely possible for players to mismatch the music
of the area and level. In fact, it's easy to do it even on accident,
especially since 2.3 now lets you quicksave and quit during cutscenes.
Just play a cutscene that has Pause music, then quicksave, quit, and
reload. Also some other accidental ways that I've forgotten about.
To fix this, I've done what mapclass has and made an areamap. Except for
music. This map is the map of the track number of every single room,
except for three special cases: -1 for do nothing and don't change music
(usually because multiple different tracks can be played in this room),
-2 for Tower music (needs to be track 2 or 9 depending on Flip Mode),
and -3 for the start of Space Station 2 (track 1 in time trials, track 4
otherwise).
I've thoroughly tested this areamap by playing through the game and
entering every single room. Additionally I've also thoroughly tested all
special cases (entering the Ship through the teleporter or main
entrance, using the Ship's jukebox, the Tower in Flip Mode and regular
mode, and the start of Space Station 2 in time trial and in regular
mode).
Closes#449.
2.3 has a regression where if you move back and forth between a zone,
you can get the wrong music playing in a zone. An example is the
Overworld and Lab. Just walk in to the Lab and immediately walk back
out, and you'll get Potential for Anything playing in the Overworld.
This regression was caused by facb079b35.
That commit removed assigning -1 to currentsong when a fadeout was
called.
Basically, the previous behavior was: currentsong is 4, we enter Lab and
nicechange gets queued to 3 but currentsong gets set to -1, then going
back nicechange gets queued to 4 again.
However, if we don't assign -1, then going back will keep nicechange at
3. Why? Because niceplay() checks for currentsong before assigning
nicechange. If currentsong is still the same then it doesn't assign
nicechange.
To fix this, just always unconditionally assign nicechange.
If spawned as a custom enemy (createentity entry 56), or spawned outside
of the rooms they spawn in in the main game, they will repeatedly clone
themselves every frame, which profusely leaks memory. In fact it quickly
causes a crash in 2.2 and previous, but 2.3 fixes that crash, so it just
keeps spawning enemies endlessly, which eventually lags the game, and
eventually can out-of-memory your system (bad!).
The problem is those movement types rely on entclass::setenemyroom() to
change their `behave` to be 11 or 13. Else, the new entity created will
still have `behave` 10 or 12, which will create ANOTHER entity in the
same way, and so on, and so forth.
So to fix this, just make it so if an enemy is still `behave` 10 or 12
by the end, then, just set it to -1. That way it'll stay still and won't
cause any harm.
I considered setting the `behave` to 11 or 13 respectively, but, that's
probably going farther than just fixing a memory leak, and anyways, it's
not that much useful for me as a custom level maker, and the entities
spawned aren't really controllable.
In order to let callers provide their OWN callback functions through the
callback function WE provide to PhysFS, we casted the function pointer
to a void pointer.
Unfortunately, this is apparently undefined behavior... if your compiler
doesn't have an extension for it. And most compilers on most
architectures do. (In fact compilers on POSIX systems most certainly
have it due to dlsym() returning a void* which could actually be a
pointer to a function sometimes.)
But imo, it's better to be safe than sorry in this regard. Especially
when given GCC's approach to optimizing int + 100 > int (spoilers: they
remove it entirely! It's faster, but also broken!).
I've decided to wrap it in a struct. And as a nice side effect, if we
ever need more data to be passed through... well we already have this
struct.
Technically, it's also standards-compliant to cast a _pointer to_ a
function pointer to a void pointer. But that extra layer of pointer
indirection would get real confusing to conceptualize real fast (or at
least is more confusing than just putting it in a struct).
Since you've been able to resume music stopped by stopmusic() with
resumemusic(), if a track was stopped by stopmusic(), the unfocus pause
itself would end up resuming the track when regaining focus.
The solution is to simply check for if music.currentsong is -1 or not.
So, platv is a room property that controls the speed of custom entity
platforms in the room (unless, of course, they're created with
createentity). Problem is, this is how 2.2-and-previous coding standards
were:
ed.level[game.roomx-100+((game.roomy-100)*ed.maxwidth)]
Overly long, verbose, not entirely clear unless you already know what it
means? Copy-pasted over and over due to all of the above? Surely a
recipe for not making any coding errors!
Ironically enough, copy-pasting is basically the best approach here
(short of refactoring the whole thing, like I did in
945d5f244a), since if you don't ACTUALLY
copy-paste and just re-type it on your own, you'll end up making more
mistakes. Like what happened here:
ed.level[game.roomx-100+((game.roomy-100)*ed.mapwidth)].platv
Do you see the mistake...? Yeah, mapwidth (with a P) instead of maxwidth
(with an X). You'd have to look closely to find it.
So what does this mean for platv? Well, it means that it multiples the
y-coordinate of the room by the map width instead of the max width (20),
like every other room property. So that means if your map width is less
than 20, like say, map width 10, the platv value for (2,2) will be
stored in (2,1)'s room properties instead of (2,2)'s. Because if you go
off of map width, the room index for (2,2) is 2 + 2 * 10 = 22, but if
you go off of max width, the room index for (2,1) is 2 + 1 * 20 = 22.
Now this wouldn't be bad, except for another 2.2-and-previous
standard... kind of just not exposing things directly to the end user.
Whether that's simply not documenting something (as in the case of
ifwarp and warpdir, which by all measures were completely intended to be
used in custom levels but just simply were never known properly until I
discovered how to use them in 2019), or in this case, not giving any way
for the user to fiddle with platv from the in-game editor. Because if
there was a way to do that, and someone decided to test to see if platv
worked okay, they would discover something was up.
So... since I refactored room properties in
945d5f244a, I kind of broke platv by
fixing it. Now levels that relied on platv being the broken way don't
work.
How do I fix it, and thus break it again? Well, I'll do what I did for
scripts - handle the scrambling when reading and writing the level, and
keep things sane at least internally.
Thus: editorclass::load() will unscramble platv data in the right way,
and editorclass::save() will re-scramble platv in the right way too.
To match the option to nuke all main game save data, there is also now
an option to nuke all custom level save data separately (which is just
all custom level quicksaves, along with stars for level completion). It
has its own confirmation menu too. It does not delete any levels from
the levels folder.
Custom level quicksaves are NOT affected by the clear data menu, so the
player should be able to delete quicksaves this way. The quicksave
confirmation menu now has an extra option to delete the save (and that
option also has its own confirmation menu before deleting).
This error case can happen, but if it does, non-console users get an
ERROR page with no further information. So use setLevelDirError if this
failure mode happens. And Menu::errorloadinglevel needs to be changed to
accomodate that.
Not sure why the original implementation decided to do things this way
instead of snprintf'ing a path to the .zip itself. Otherwise, if the
level is from data.zip, PHYSFS_getRealDir() will return the path of
data.zip, which then fails to mount for separate reasons.
Since createentity() started accepting p1/p2/p3/p4 arguments, it now
unconditionally passes in whatever arguments were present there
previously, when there weren't any before.
This can lead to unexpected behavior when selectively using and then
omitting p1/p2/p3/p4 arguments.
Also, plenty of existing levels already only use the 5-argument version
of createentity(). And createcrewman() can take up to 6 arguments at
once. It's not far-fetched that an existing level could createentity()
right after doing a 6-argument createcrewman(), which would lead to a
different behavior than in 2.2 and previous.
So instead, instead of checking if `words[index]` is an empty string (it
only sets the string to be empty if there are enough argument separators
on the line), ACTUALLY check if it's empty. I've added a static array
(no need for it to be exported) that keeps track of this. createentity()
now checks for that instead of `words`.
It's possible to get one page of levels by removing all the built-ins,
either by removing them directly from data.zip or by putting files with
the same filenames as them in your level folder that don't contain
nothing.
And hey, there's already a check for if no levels exist at all, so why
not check for this too?
Previously, you would only get the trinket completion star if you got
the exact same amount of trinkets as there are custom entity trinkets in
the level file. But if you got more (say, if the level spawned extra
"bonus trinkets"), you wouldn't be able to get the star.
This is true of the custom crewmate case as well, but I've decided to
not change that case, because there are still downsides to the resulting
behavior and it's better to just leave it alone because it's rare for it
to happen anyways.
Since custom levels have gained the functionality to show trinkets on
the minimap, it's nice to just save the showtrinkets variable directly
to the save file, without having to make level makers handle it
themselves.
If you have unfocus pause off, and unfocus audio pause off, then this command will go into effect.
When it's set to on, the audio will pause when you unfocus the game. When it's set to off, the
audio will not. This is different from the setting, and gets saved to the save file.
If a zip file is improperly structured, a message will be displayed when
the player loads the level list.
This will only display the last-displayed improper zip, because there
only needs to be one displayed at a time. Also because doing anything
more would most likely require heap allocation, and I don't want to do
that.
This will wrap text on-the-fly, since I will be introducing text that
needs to be wrapped whose length we can't know in advance. (Or we can,
but, that'd be stupid.)
I took the algorithm from Dav999's localization branch, but it's not
like it's a complicated algorithm in the first place. Plus I think it
actually handles words that get too long to fit on a single line better
than his localization branch. The only difference is that I removed all
the STL, and made it more memory efficient (unlike his localization
branch, it does not copy the entire string to make a version with
newline separator characters).
This macro needs to be used because Clang is stupid and doesn't let you
use /* fallthrough */ comments like GCC does. However, if GCC is too old
(as is the case on CentOS 7), then it won't recognize __has_attribute
either.
Some people prefer the 2.2 behavior where unfocusing pauses the game,
but the music still plays. One such person is Trinket9 on the VVVVVV
Discord server, who wanted it that way.
The reason audio pausing was added in the first place was to prevent
desyncing music in levels with cutscenes that synced to music. Rather
than reverting it, let's add this option instead.
Similar to disabling the elephant flashiness, at least one
photosensitive person has told me the flashy color animation makes their
eyes kind of hurt a little bit. Also it screws up the compression really
badly when they record (especially the green noisy tiles!).
The colors will still cycle, but the individual animations within each
color will be completely static.
It's quite rude to close the game. Especially if the user does not use
the console. They won't know why the game closed.
Instead, just return -1. All usages of font_idx() should be and are
bounds checked anyways. This will result in missing characters, but,
it's not like the characters had a font image in the first place,
otherwise we wouldn't be here. And if the user sees a bunch of
characters missing in their font, they'll probably work out what the
problem is even without having a console. And it's still far better than
abruptly closing the game.
And use WHINE_ONCE to prevent spamming the console.
Let's say you have a zip named LEVELNAME.zip, but the only .vvvvvv file
it contains is NOTLEVELNAME.vvvvvv. This zip would end up printing both
the 'LEVELNAME.vvvvvv is missing' and 'It has .vvvvvv file(s) other than
LEVELNAME.vvvvvv' messages, even though we already know there's
something wrong with the zip, and the 'other level files' message is
redundant, since in this case the problem here is simply just the
.vvvvvv file being named the wrong way.
The 'other level files' message is only intended to be printed when
LEVELNAME.vvvvvv *does* exist, but there's additional .vvvvvv files in
the zip on top of that, so don't print this message if LEVELNAME.vvvvvv
exists.
Since colors going into FillRect() need to be in BGR format, we need to
use getBGR instead. (Well, actually, it gets passed in RGB, but then at
some point the order gets switched around, and, really, this game's
masks are all over the place, I'm going to fix that in 2.4.)
This can happen if you select an option in a menu that (A) returns to
the previous menu and (B) saves settings. If the settings save fails,
this will create another menu on the same frame that cycles the tower BG
after it's already been cycled for that frame. Examples are the slowdown
and glitchrunner menus.
I could fix this by creating a new function that copy-pastes all of
Game::savestatsandsettings_menu() except for the map.nexttowercolour()
at the end. But that's copy-pasting code.
Instead what I've done is added a variable to signal if the color has
already been cycled this frame, so we don't cycle it again. This also
covers cases of possible double-cycling in the future as well.
This is because the fade delay did not last long enough.
I was under the mistaken impression that the fade animation lasts for 15
frames. However, this does not account for the fact that the offset of
each fade bar is dependent on RNG, and the worst case scenario is that
they have an offset of 96 pixels (in the opposite direction of the
fade).
The actual fade animation timer accounts for the worst case scenario, so
the fade animation actually lasts for (320 pixels plus 96 pixels is 416
pixels, 416 pixels divided by 24 pixels per frame equals 17.333...
frames, but since the actual timer keeps adding/subtracting 24 pixels
per frame until it passes the 416-pixel threshold, that gets rounded up
to...) 18 frames.
And an extra frame to make it so deltaframe interpolation doesn't
suddenly stop on the last deltaframes before the screen is completely
black.
I also need to draw the screen black on the map screen when glitchrunner
mode is off, if there's a fadeout going on. Else that would introduce
yet another frame flicker.
This fixes a bug where the player would always be facing right if they
were loading in for the first time. This essentially made them always
ignore the facing direction set in the save file if the facing direction
was leftwards.
The problem is facing direction only gets set in map.resetplayer(), but
if loading in for the first time, that path is never taken (unless you
are loading a main game quicksave that's inside a tower). The solution
is to always reset the player, even after creating them for the first
time.
This fixes being able to re-trigger the fadeout while a fadeout is
already happening. It also fixes being able to enter playtesting during
the fadeout, which means the level now has a fadeout you normally can't
do in actual gameplay.
There's nothing to interpolate. It moves at one pixel per frame. And
interpolating sometimes results in the box being short by 1 pixel to
cover the whole screen on deltaframes, so if you stand on the right edge
of the screen and have a translucent sprite, it will quickly draw over
itself many times, and it looks glitchy. This commit fixes that bug.
Previously, turning glitchrunner mode on essentially locked you to
emulating 2.0, and turning it off just meant normal 2.3 behavior. But
what if you wanted 2.2 behavior instead? Well, that's what I had to ask
when a TAS of mine would desync in 2.3 because of the two-frame delay
fix (glitchrunner off), but would also desync because of 2.0 warp lines
(glitchrunner on).
What I've done is made it so there are three states to glitchrunner mode
now: 2.0 (previously just the "on" state), 2.2 (previously a state you
couldn't use), and "off". Furthermore, I made it an enum, so in case
future versions of the game patch out more glitches, we can add them to
the enum (and the only other thing we have to update is a lookup table
in GlitchrunnerMode.c). Also, 2.2 glitches exist in 2.0, so you'll want
to use GlitchrunnerMode_less_than_or_equal() to check glitchrunner
version.
Two problems: the fRandom() range was from 0..36, but that's 37
characters, not 36. And the check to sort the lower 26 values into the
Latin alphabet used a 'lesser-than-or-equal-to 26' check, even though
that checks for the range of values of 0..26, which is 27 letters, even
though the alphabet only has 26 letters. So just drop the equals sign
from that check.
It was checking for .vvv-mnt-temp-XXXXXX/LEVELNAME.vvvvvv instead of
LEVELNAME.vvvvvv. When PhysFS enumerates the folder, it only gives us
LEVELNAME.vvvvvv, and not .vvv-mnt-temp-XXXXXX/LEVELNAME.vvvvvv.
This fixes a regression that desyncs my Nova TAS after re-removing the
1-frame input delay.
Quick stopping is simply holding left/right but for less than 5 frames.
Viridian doesn't decelerate when you let go and they immediately stop in
place. (The code calls this tapping, but "quick stopping" is a better
name because you can immediately counter-strafe to stop yourself from
decelrating in the first place, and that works because of this same
code.)
So, the sequence of events in 2.2 and previous looks like this:
- gameinput()
- If quick stopping, set vx to 0
- gamerender()
- Change drawframe depending on vx
- gamelogic()
- Use drawframe for collision (whyyyyyyyyyyyyyyyyyyyyyyyyyyy)
And now (ignoring the intermediate period where the whole loop order was
wrong), the sequence of events in 2.3 looks like this:
- gamerenderfixed()
- Change drawframe depending on vx
- gamerender()
- gameinput()
- If quick stopping, set vx to 0
- gamelogic()
- Use drawframe for collision (my mind has become numb to pain)
So, this means that all the player movement stuff is completely the
same. Except their drawframe is going to be different.
Unfortunately, I had overlooked that gameinput() sets vx and that
animateentities() (in gamerenderfixed()) checks vx. Although, to be
fair, it's a pretty dumb decision to make collision detection be based
on the actual sprites' pixels themselves, instead of a hitbox, in the
first place, so you'd expect THAT to be the end of the dumb parade. Or
maybe you shouldn't, I don't know.
So, what's the solution?
What I've done here is added duplicates of framedelay, drawframe, and
walkingframe, for collision use only. They get updated in gamelogic(),
after gameinput(), which is after when vx could be set to 0.
I've kept the original framedelay, drawframe, and walkingframe around,
to keep the same visuals as closely as possible.
However, due to the removal of the input delay, whenever you quick stop,
your sprite will be wrong for just 1 frame - because when you let go of
the direction key, the game will set your vx to 0 and the logical
drawframe will update to reflect that, but the previous frame cannot
know in advance that you'll release the key on the next frame, and so
the visual drawframe will assume that you keep holding the key.
Whereas in 2.2 and below, when you release a direction key, the player's
position will only update to reflect that on the next frame, but the
current frame can immediately recognize that and update the drawframe
now, instead of retconning it later.
Basically the visual drawframe assumes that you keep holding the key,
and if you don't, then it takes on the value of the collision drawframe
anyway, so it's okay. And it's only visual, anyway - the collision
drawframe of the next frame (when you release the key) will be the same
as the drawframe of the frame you release the key in 2.2 and below.
But I really don't care to try and fix this for if you re-enable the
input delay because it's minor and it'd be more complicated.
In the past, people have reported having glitched levels where they
can't get the trinket star or can't complete the level because the
number of trinkets or crewmates is one higher than what can be obtained
in the level.
How did this happen? Well, it turns out that if you place an entity, and
then resize the level to be smaller, that entity still exists. This is
inconsequential for most entities, but if the entity is a trinket or
crewmate, that entity is still counted towards the number of trinkets or
crewmates in the level.
One fix would be to just remove entities whenever the level is
downsized, but then if someone accidentally downsizes the level and
wants to go back, that entity will be gone. Plus, it would be
inconsistent with tiles, because tiles don't get removed when you
downsize the level. Also, it wouldn't fix existing levels where people
have managed to place trinkets or crewmates out of bounds.
So instead, ed.numtrinkets() and ed.numcrewmates() should simply ignore
trinkets and crewmates that are outside the playable area. That way,
levels with glitched trinkets and crewmates can still be completed, and
can still be completed with the trinket star.
This fixes a regression where you're unable to activate activity zones
in in-editor playtesting if your interact button is not separate from
the map button.
When I originally did #743, I didn't have an option to set the bind to
be non-separate, so I removed this logic without adding a
game.separate_interact check. But when I added the option, I overlooked
this code, and so this regression happened. Whoops.
Not every music path will trip the quick_fade bool that resets the timer to
500ms, so we need to do this as soon as it's asked of us. This fixes the fade
when quitting to the main menu.
Fixes#764
Without this you end up with two problems:
- Fades will start past their fade time, causing it to just not fade at all
- Fades will start in the middle of their fade time, causing dramatic changes
in volume that are unintentional
The fade system already preserves the volume that music is playing during a
previous fade, so we can always reset the timer and get a good result.
Part of #764
This fixes one of two desyncs in my Nova TAS.
The problem is that by adding two frames of edge-flipping to vertically
moving platforms, Viridian's framedelay is updated for one extra frame
after they step off of a vertically-moving platform. This then messes up
Viridian's drawframe for the rest of the TAS until they die in a
drawframe-sensitive trick.
The solution here is to only set the visual onroof/onground to 1
instead. The logical onroof/onground is still 2, so players still have
two frames of edge-flipping off of vertically-moving platforms - it just
won't really look like it (not that you could easily tell anyway).
- use fseeko and ftello like FreeBSD in tinyxml2
- use current directory as basePath if NULL (OpenBSD doesn't actually support this feature it is disabled via a patch in their ports)
In order to help players spot the difference between outlined text and
non-outlined text, we now outline the text outline text itself (if text
outline is enabled, of course). But drawing the outline alone doesn't
stand out enough, so we have to draw a solid backing against the text as
well, in order to properly show the contrast.
This fixes a regression where you're able to start flipped by restarting
and then holding ACTION.
This happens because when the game resets all variables, it turns
hascontrol back on (because of hardreset()). However, this is handled in
the input function, and it's handled before player input is handled, so
the player is able to get 1 frame of being able to flip after a time
trial resets.
Why didn't this happen in 2.2? Because resetplayer() in 2.2 would set
lifeseq to 10, as if the player had died. However, this is inconsistent,
because loading in to the game for the first time would not result in a
lifeseq of 10. So, in 2.2, restarting the time trial would remove that 1
frame of being able to flip because of lifeseq, while 2.3 doesn't set
lifeseq because the player hasn't died.
I could have fixed this by setting lifeseq in the time trial restart
code, but I decided to just set hascontrol to false instead.
Fixes#770.
In earlier 2.3, if the roomname was empty, Dimension VVVVVV was used
instead. However, instead of doing that, it's better to just use the
hiddenname instead. Both because it's less hardcoded, and some rooms
have hidden names that aren't Dimension VVVVVV.
This makes the text much more readable against certain backgrounds (if
you have text outline enabled), especially against the Warp Zone
background (when you start in "This is how it is").
If you enter the Secret Lab from the title screen, all rooms will be
explored. However, if you enter the Secret Lab via the Secret Lab
entrance cutscene (epilogue), not all rooms will be explored, which is
inconsistent.
To do this, just do an SDL_memset() for the entersecretlab script
command.
SDL_memset() conveys intent better and is snappier than using a
for-loop. Also, using SDL_memset() to explore all rooms is more
future-proof, in case the size of map.explored were to change in the
future, and it's more conducive to optimization.
However, the `i` variable has to be explicitly set because it was
previously used here, but it's much better that it's explicitly set here
rather than being subtlely hidden in the inner for-loop initialization.
This is more future-proofing than anything else. The position of the
indicators is just the x-position of the gravitron square divided by 10,
but the gravitron squares will always only ever move at 7 pixels per
frame - so the distance an indicator travels on each frame will only
ever be at most 1 pixel. But just in case in the future gravitron
squares become faster than 10 pixels per frame, their indicators will be
interpolated as well.
When rollcredits is ran during in-editor playtesting, all unsaved data
is lost. To prevent this, just return to the editor if rollcredits is
ran, with a note saying "Rolled credits".
The text box drawn at the bottom of the map screen isn't wide enough, so
it's possible to see the corners on the right side of the text box if
you have custom graphics like I do.
The solution is to increase the width of the text box by one tile.
The game automatically writes settings to disk after any other setting
is changed, so it should do the same whenever the user changes
controller keybinds.
For consistency, the Viridian squeak will now play whenever you start
editing a level description field, or finish editing it (either by
pressing Esc or Enter).
If a level zip is named LEVELNAME.zip, the level file inside it must
also be named LEVELNAME.vvvvvv, else custom assets won't work.
This is because when we mount the zip file, we simply add
LEVELNAME.vvvvvv to the levels directory. Then whenever we load
LEVELNAME.vvvvvv, we look at the filename, remove the extension, and
look for the assets inside the zip of the same name, LEVELNAME.zip.
As a result, if someone were to make a level zip with assets but
mismatch the filename, the assets wouldn't load. Furthermore, if someone
were to add extra levels in the same zip, they wouldn't have any assets
load for them as well, which could be confusing.
To make things crystal-clear to the user, we now filter out any zips
that have incorrect structures like that, and print a message to the
terminal. Unfortunately nothing gets shown for non-terminal users, but
at least doing this and filtering out the zips is less confusing than
letting them through but with the issues mentioned above.
FILESYSTEM_mountAssets() has a big comment describing the magic numbers
needed to grab FILENAME from a string that looks like
"levels/FILENAME.vvvvvv".
Instead of doing that (and having to write a comment every time the
similar happens), I've written a macro (and helper function) instead
that does the same thing, but clearly conveys the intent.
I mean, just look at the diff. Using VVV_between() is much better than
having to read that comment, and the corresponding SDL_strlcpy().
This is so it can be reused without having to copy-paste.
generateBase36() is guaranateed to completely initialize and
null-terminate the buffer that is passed in.
This fixes a bug where the player's y-position would be incorrect if
they loaded a save that was on a conveyor and it was their first time
loading in since the game was opened.
This is because on the first load, the game creates a new player entity,
but on subsequent loads, the game re-uses the player entity. Subsequent
loads use mapclass::resetplayer(), which already has the newxp/newyp
fix, but as for the first time, the game does not set newxp/newyp.
So just set newxp/newyp, like in mapclass::resetplayer().
Upon further discussion it was decided to keep the soundtrack as originally
shipped, instead of changing it after the fact.
This reverts commit cf51379097.
There is a pattern in the Super Gravitron that is meant to "staircase",
similar to the Gravitron in Intermission 2. Something like:
[]
[]
[]
[] []
[] []
Unfortunately, due to an oversight, this pattern can only ever produce 1
square or 4 squares, which look out of place.
Both gravitrons are state machines (of course). States 20 and 21 in the
Super Gravitron are this staircase pattern (state 20 spawns the squares
on the left, state 21 spawns the squares on the right).
The only way states 20 and 21 can be reached is through state 1, and the
only way state 1 can be reached is through state 3. The only way state 3
can be reached is through states 28, 29, 30, and 31.
In states 20 and 21, the variable used to keep track of the amount of
squares spawned is swnstate4. However, states 28, 29, 30, and 31 all end
up using swnstate4, and at the end of states 28 and 29, swnstate4 will
be 7, and at the end of states 30 and 31, swnstate4 will be 3. This
means if we go to states 20 and 21 after coming from states 28 and 29,
we will only get 1 square, and if we go to states 20 and 21 after coming
from states 30 and 31, we will only get 4 squares.
This can be clearly filed under a failure to reset appropriate state.
What's the solution here? Just reset swnstate4 in state 3, so there will
be 7 squares, as intended. This also fixes the bug for state 22 as well,
which is affected in the same manner.
This fixes an oversight that could lead to confusion by the player.
showtargets is the variable that shows all unexplored teleporters on the
map as a question mark, so players know where to head to to make
progress. However, it previously was not directly saved to the main game
file. Instead, it would be set to true if flag 12 was turned on in the
save file.
How well does flag 12 correlate with showtargets?
Well, the script that turns on showtargets (bigopenworld and
bigopenworldskip) doesn't turn it on. Neither does completing Space
Station 1.
This flag is only turned on when the player activates Violet's activity
zone for the first time.
Therefore, it's entirely possible that a new player could complete Space
Station 1, then save their game, and come back to resume playing later.
When they do come back, the question marks that Violet told them about
won't show up on the minimap, and they'll be confused. They may not know
where to go.
And it is completely unintuitive for them to know that in order to get
the question marks to show up again, they have to not only talk to
Violet, but then save the game again, and reload the save. Especially
since the question marks only show up after you reload the save, and not
when you talk to Violet (because flag 12 is only a proxy for
showtargets, not the actual variable itself).
So what's the solution? Just save showtargets to the save file directly.
If you have invincibility enabled, the tower camera behavior is
inconsistent.
In ascending towers, you can "push" the camera upwards; however you
cannot push it downwards; at least it stays still when it comes up to
you if you stay still. In descending towers, the camera moves quicker
when you're at the bottom of the screen, but it's slower than your
falling speed and quickly loses sight of you; the camera can be pushed
upwards; unfortunately it also does a "bumping" motion if you're
standing still when the camera reaches you, which gets real annoying and
isn't particularly pleasant to look at.
There are two problems, so this does two fixes:
1. Pushing the camera now applies the appropriate counter-offset
depending on the direction of the tower. You can now push the camera
downwards in ascending towers.
2. To fix the "bumping" when the camera reaches you if you stand still,
there are now a 8-pixel-high "gray areas" at the top and bottom of
the screen where the camera simply won't move if you're in them.
Doing these camera offsets instead of simply canceling the movement if
the player is offscreen is a bit ugly... but it works for now.
This is a lot of copy-pasted code, but a little bit of copy-pasting
never hurt anyone...
The keybind to interact with activity zones and teleporters is now
separate from the keybind to open the map, or return to the editor from
in-editor playtesting, or restart a time trial. The keybind is now E,
and the default controller bind is X. No controller button prompts, but
the game didn't have controller button prompts anyways, so whatever.
Doing this now because if people's muscle memory are going to be broken
by not being able to spam the map keybind anymore, at least we can help
a bit by changing the keybind so they can keep spamming it - their
muscle memory is going to be broken anyways.
This option has to be enabled by going to the speedrunner menu options
and selecting "interact button". It is disabled by default.
All prompt text needs to be string-interpolated every time they are
drawn, because it is possible for people to change which interact button
they use in the middle of gameplay, via the in-game options.
Closes#736.
Colors in over-30-FPS mode shouldn't be updating every deltaframe;
mostly to ensure determinism between switching 30-mode and over-30 mode.
I'm going to overhaul RNG in 2.4 anyway, but right now I'm going to fix
this because I missed it.
The RNG of each special text box is stored in a temporary variable on
the text box itself, and only updated if the color uses it (hence the
big if-statement). Lots of code duplication, but this is acceptable for
now.
After the dimension destabilizes, the song that plays is Positive Force.
Which has already been played twice in the game at that point (first in
Tower, then in the Gravitron). Since Piercing the Sky is unused, why not
play a song that the player hasn't heard before? It would also be
musically fitting for the scenario.
The song gets played in two places - one for if you have cutscenes
enabled, and one for if you don't - so we just need to change both of
them.
I asked Terry in Discord DMs if he wanted this change and he approved of
it.
If you have completed No Death Mode, and entered the Master of the
Universe trophy room in the Secret Lab in over-30-FPS mode, it would
appear to start at one position before quickly zipping to another during
the deltaframes.
This is because it updates its position after the initial assignments of
lerpoldxp/lerpoldyp in entityclass::createentity().
Other entities do this too, and what's been done for them is to
copy-paste the lerpoldxp/lerpoldyp updates alongside the xp/yp updates.
However, instead of single-case patching this deltaframe glitch, I've
opted to fix ALL cases by simply moving the lerpoldxp/lerpoldyp
assignments to the end of the function, guaranteeing that all entities
that update their position after the initial assignment in the function
will not have any deltaframe glitches.
Of course, there's still the duplicate lerpoldxp/lerpoldyp updates in
entityclass::updateentities()... I'm not sure what to do about those.
If you had Flip Mode enabled when exiting from in-game options, the game
would flash the in-game options menu as flipped for 1 frame before
returning to the pause menu.
To fix this, just defer the Flip Mode variable assignment to be done at
the end of the frame.
This is a small quality-of-life fix in the same vein as allowing the
player to press Esc in the teleporter menu (which they weren't able to
do in 2.2, either).
This fixes the finalstretch tile shifting persisting if you return to
the main dimension and final_colormode isn't reset properly.
It's possible to do so in the main game by using a teleporter in
finalmode while having the Intermission 1 or 2 companion active.
For custom levels, level makers can make a setup that automatically
turns on finalstretch, goes to finalmode, and then returns to the main
dimension. The only thing being... as a level maker myself, this tile
shifting REALLY doesn't seem useful (and no one has ever used it because
the setup to do so hadn't really been found or documented until this
year). For one, the exact shift is randomized every time (there's an
fRandom() call to cycle the colors). For two, it goes away after the
player saves and reloads the level. And for three, it doesn't animate
like it does in finalmode (this is the biggest reason IMO).
Nevertheless, I've decided to keep support for this in custom levels, in
case someone in the future does want to use it and is okay with the
limitations.
There's a bit of inconsistency with how long each color lasts for during
final stretch. Initially, each color lasts for 40 frames, but when you
enter either of the minitowers, the color switches to lasting for 15
frames only. This is because a final_colorframe of 1 makes it go for 40
frames, but a final_colorframe of 2 makes it go for 15 frames - and
final_colorframe gets set to 2 whenever you enter a minitower.
This seems like an oversight because (1) final_colorframe doesn't affect
anything inside the minitower, (2) final_colorframe doesn't get saved to
the save file and always gets set to 1 if your save file has
finalstretch set to true, so saving and reloading will set the colors
back to 40 frames each, and (3) final_colorframe doesn't get set back to
1 when leaving the minitowers.
When you enter the Super Gravitron, you have to wait until the Super
Gravitron actually starts before being able to press Enter to return to
the Secret Lab. This is annoying if you just want to get back to the
Secret Lab. So, I've made it so the press-Enter-to-return functionality
is enabled from the moment that the Super Gravitron starts.
It turns out, despite the game attempting to prevent you from using
invincibility or slowdown in the Super Gravitron by simply preventing
you from entering the Secret Lab from the menu, it's still possible to
enter the Super Gravitron with it anyways. Just have invincibility or
slowdown (or both!) enabled, enter the game normally, and talk to
Victoria when you have 20 trinkets, to start the epilogue cutscene.
Yeah, that's a pretty big gaping hole right there...
It's also possible to do a trick that speedrunners use called
telejumping to the Secret Lab to bypass the invincibility/slowdown
check, too.
So rather than single-case patch both of these, I'm going to fix it as
generally as possible, by moving the invincibility/slowdown check to the
gamestate that starts the Super Gravitron, gamestate 9. If you have
invincibility/slowdown enabled, you immediately get sent back to the
Secret Lab. However, this check is ignored in custom levels, because
custom levels may want to use the Super Gravitron and let players have
invincibility/slowdown while doing so (and there are in fact custom
levels out in the wild that use the Super Gravitron; it was like one of
the first things done when people discovered internal scripting).
No message pops up when the game sends you back to the Secret Lab, but
no message popped up when the Secret Lab menu option was disabled
previously in the first place, so I haven't made anything WORSE, per se.
A nice effect of this is that you can have invincibility/slowdown
enabled and still be able to go to the Secret Lab from the menu. This is
useful if you just want to check your trophies and leave, without having
to go out of your way to disable invincibility/slowdown just to go
inside.
This factors out the slowdown and invincibility conditionals to a
function. This means less copy-pasted code, and it also conveys intent
(that we don't want to allow competitive options if we have either of
these cheats enabled).
This function isn't implemented in the header because then we would have
to include Map.h for map.invincibility, and transitive includes are
evil. Although, map.invincibility ought to be on Game instead (it was
only mapclass due to 2.2-and-previous argument passing), but that's a
bunch of variable reshuffling that can be done later.
They are now factored out to an inline function named incompetitive().
This is so their usage can be changed without having to change each
individual one in every place. This also clarifies the intent of using
these conditionals (they are for when we're in a "competitive" mode).
Tower backgrounds have a bypos and bscroll. bypos is just the y-position
of the background, and bscroll is the amount of pixels to scroll the
background by on each frame, which is used to scroll it (if it's not
being redrawn) and for linear interpolation.
For the tower background (and not the title background), bypos is
map.ypos / 2, and bscroll is (map.ypos - map.oldypos) / 2. However,
usually bscroll gets assigned at the same time bypos is incremented or
decremented, so you never see that calculation explicitly - except in
the previous commit, where I worked out the calculation because the
change in y-position isn't a known constant.
Having to do all these calculations every time introduces the
possibility of errors where you forget to do it, or you do it wrongly.
But that's not even the worst; you could cause a linear interpolation
glitch if you decide to overwrite bscroll without taking into account
map.oldypos and map.ypos.
So that's why I'm adding a function that automatically updates the tower
background, using the values of map.oldypos and map.ypos, that is used
every time map.ypos is assigned. That way, we have to write less code,
you can be sure that there's no place where we forget to do the
calculations (or at least it will be glaringly obvious) or we do it
wrongly, and it plays nicely with linear interpolation. This also
replaces every instance where the manual calculations are done with the
new function.
