The script command createentity() is always an int. But not only that,
every time createentity() is used, its arguments are always treated like
ints. Always. I knew that vx/vy were floats because of the int casts in
the function, but I didn't even realize that xp/yp were floats, too,
until I checked just now! That's how much they're treated like ints.
All int casts in createentity() have also been removed, due to being
unnecessary (either because of us suppressing MSVC implicit conversion
warnings, or because there are now no longer any conversions happening).
During the final stretch, after Viridian turns off the Dimensional
Stability Generator, the map goes all psychedelic and changes colors
every 40 frames. Entities change their colors too, including conveyors,
moving platforms, and disappearing platforms.
But play around with the disappearing platforms for a bit and you'll
notice they seem a bit glitchy. If you run on them at the right time,
the tile they use while disappearing seems to abruptly change whenever
the color of the room changes. If there's a color change while they're
reappearing (when you die and respawn in the same room as them), they'll
have the wrong tile and look like a conveyor. And even if you've never
interacted with them at all, dying and respawning in the same room as
them will change their tile to something wrong and also look like a
conveyor.
So, what's the problem? Well, first off, the tile of every untouched
disappearing platform changing into a conveyor after you die and respawn
in the same room is caused by a block of code in gamelogic() that gets
run on each entity whenever you die. This block of code is the exact
same block of code that gets ran on a disappearing platform if it's in
the middle of disappearing.
As a quick primer, every entity in the game has a state, which is just a
number. You can view each entity's state in
entityclass::updateentities().
State 0 of disappearing platforms is doing nothing, and they start with
an onentity of 1, which means they turn to state 1 when they get
touched. State 1 moves to state 2. State 2 does some decrementing, then
moves to state 3 and sets the onentity to 4. State 3 also does nothing.
After being touched, state 4 makes the platform reappear and move to
state 5, but state 5 does the actual reappearing; state 5 then sets the
state back to 0 and onentity back to 1.
So, back to the copy-pasted block of code. The block of code was
originally intended to fast-forward disappearing platforms if they were
in the middle of disappearing, so the player respawn code would properly
respawn the disappearing platform, instead of leaving it disappeared.
What it does is keep updating the entity, while the state of the entity
is 2, until it is no longer in state 2, then sets it to state 4.
Crucially, the original block of code only ran if the disappearing
platform was in state 2. But the other block of code, which was
copy-pasted with slight modifications, runs on ALL disappearing
platforms in final stretch, regardless of if they are in state 2 or not.
Thus, all untouched platforms will be set to state 4, and state 4 will
do the animation of the platform reappearing, which is invalid given
that the platform never disappeared in the first place. So that's why
dying and respawning in the same room as some disappearing platforms
during final stretch will change their tiles to be conveyors.
It seems to me that doing anything with death is wrong, here. The root
cause is that map.changefinalcol() "resets" the tile of every
disappearing platform, which is a function that gets called on every
color change. The color change has nothing to do with dying, so why
fiddle with the death code?
Thus, I've deleted that entire block of code.
What I've done to fix the issue is to make it so the tile of
disappearing platforms aren't manually controlled. You see, unlike other
entities in the game, the tile of disappearing platforms gets manually
modified whenever it disappears or reappears. Other entities use the
tile as a base and store their tile offset in the separate walkingframe
attribute, which will be added to the tile attribute to produce the
drawframe, which is the final thing that gets rendered - but for
disappearing platforms, their tile gets directly incremented or
decremented whenever they disappear or reappear, so when
map.changefinalcol() gets ran to update the tile of every platform and
conveyor, it basically discards the tile offset that was manually added
in.
Instead, what I've done is make it so disappearing platforms now use
walkingframe, and thus their final drawframe will be their tile plus
their walkingframe. Whenever map.changefinalcol() gets called, it is now
free to modify the tile of disappearing platforms accordingly - after
all, the tile offset is now stored in walkingframe, so no weird
glitchiness can happen there.
Custom levels can have warp lines. If you have a warp line and a warping
background in the same room, the warp line takes precedence over the
warp background.
However, whenever you enter a room with a warp line and warp background,
any entities on the warping edges will be drawn with screenwrapping for
one frame, even though they never wrapped at all.
This is due to frame ordering: when the warp line gets created,
obj.customwarpmode gets set to true. Then when the screen edges and
warping logic gets ran, the very first thing that gets checked is this
exact variable, and map.warpx/map.warpy get set appropriately - so
there's no way the entity could legitimately screenwrap.
However, that happens in gamelogic(). gamelogic() is also the one
responsible for creating entities upon room load, but that happens after
the obj.customwarpmode check - so when the game gets around to rendering
in gamerender(), it sees that map.warpx or map.warpy is on, and draws
the screenwrapping, even though map.warpx/map.warpy aren't really on at
all. Only when gamelogic() is called in the frame later do map.warpx and
map.warpy finally get set to false.
To fix this, just set map.warpx and map.warpy to false when creating
warp lines.
I just spotted this one - if vy isn't bounds-checked, this causes bogus
input from the createentity() script command to commit Undefined
Behavior. Should've spotted this one when I was adding bounds checks to
the rest of createentity() earlier, but at least it's fixed now.
This replaces all raw ed.level accesses with new setter and getter
funcs, which makes it easier to add bounds checks later. And I've also
removed all the manually-written bounds checks, since they will go into
the new getter and setter.
To get the room properties of a specific room, you use
editorclass::getroomprop(), which returns a pointer to the room
properties - then you just read off of that pointer. To set a room
property, you use editorclass::setroom<PROP>(), where <PROP> is the name
of the property. These are maintained using X macros to avoid
copy-pasting. editorclass::getroompropidx() is a helper function and
shouldn't be used directly.
I will need to separate these into two different variables because I
will need to move logical onground/onroof assignments to the start of
gamelogic() - if I kept them together, however, that would change the
visuals of onground/onroof, which I want to keep consistent with 2.2.
This once again fixes the facing directions of crewmates upon room load,
except now it covers more cases.
So, here is the saga so far:
- 2.0 (presumably) to 2.2: crewmate direction fix is special-cased at
the end of mapclass::loadlevel(). Only covers crewmates created during
the room load, does not cover crewmates created from scripts, only
covers state 18 of crewmates.
- 2.3 currently (after #220): crewmate direction fix is moved to
entityclass::createentity(), which covers every avenue of crewmate
creation (including from scripts), but still only covers state 18.
- This commit: crewmate direction fix now covers every possible state of
the crewmate, also does not copy-paste any code.
What I've done instead is to make it so createentity() will immediately
call updateentities() on the pushed-back entity. This is kludge-y, but
is completely okay to do, because unlike other entities, crewmate
entities never change their state or have any side-effects from
double-evaluation, meaning calling updateentities() on them is
idempotent and it's okay to call their updateentities() more than once.
This does have the slight danger that if the states of crewmates were to
change in the future to no longer be idempotent, this would end up
resulting in a somewhat hard-to-track-down double-evaluation bug, but
it's worth taking that risk.
This fix is not applied to entity 14 (the supercrewmate) because it is
possible that calling updateentities() on it will immediately remove the
entity, which is not idempotent (it's changing the state of something
outside the object). Supercrewmates are a bit difficult to work with
outside of the main game anyways, and if you spawn them you could
probably just use the changedir() script command to fix their direction,
so I'm not inclined to fix this for them anyway.
This copy-pasted code only existed because the previous loop order was
incorrect and rendered entities before they would get properly updated
by the fixed render function. Now, the fixed render function is
guaranteed to be called before the render function, so we can rely on
that to update the drawframe and realcol of entities instead of
duplicating the code ourselves in createentity().
The drawframe assignment is still kept to fix the case where dying while
completestop is active (i.e. during a trinket or crewmate rescue
cutscene) and respawning in a different room won't turn everything into
Viridian sprites.
These float attributes are assigned to, and then never read again. The
coordinate systems of blocks are a bit of a mess - some use xp/yp, some
use xp/yp and rect.x/rect.y - but I can confidently say that these are
never used, because it compiles fine if I remove the attributes from the
class, plus remove all assignments to it.
Apparently in C, if you have `void test();`, it's completely okay to do
`test(2);`. The function will take in the argument, but just discard it
and throw it away. It's like a trash can, and a rude one at that. If you
declare it like `void test(void);`, this is prevented.
This is not a problem in C++ - doing `void test();` and `test(2);` is
guaranteed to result in a compile error (this also means that right now,
at least in all `.cpp` files, nobody is ever calling a void parameter
function with arguments and having their arguments be thrown away).
However, we may not be using C++ in the future, so I just want to lay
down the precedent that if a function takes in no arguments, you must
explicitly declare it as such.
I would've added `-Wstrict-prototypes`, but it produces an annoying
warning message saying it doesn't work in C++ mode if you're compiling
in C++ mode. So it can be added later.
This fixes a regression where moving platforms had no collision. Because
their width and height would be maintained, but their type would be -1.
(Also because I didn't test enough.)
In #565, I decided to set blocks' types to -1 when disabling them, to be
a bit safer in case there was some code that used block types but not
their width and heights. However, this means that when blocks get
disabled and re-created in the platform update loops, their types get
set to -1, which effectively also disables their collision.
In the end, I'll just have to compromise and remove setting blocks to
type -1. Because in a better world, we shouldn't be destroying and
creating blocks constantly just to move some platforms - however, fixing
such a fundamental problem is beyond the scope of at least 2.3 (there's
also the fact that this problem also results in some bugs that are a
part of compatibility, whether we like it or not). So I'll just remove
the -1.
This patch restores some 2.2 behavior, fixing a regression caused by the
refactor of properly using std::vectors.
In 2.2, the game allocated 200 items in obj.entities, but used a system
where each entity had an `active` attribute to signify if the entity
actually existed or not. When dealing with entities, you would have to
check this `active` flag, or else you'd be dealing with an entity that
didn't actually exist. (By the way, what I'm saying applies to blocks
and obj.blocks as well, except for some small differing details like the
game allocating 500 block slots versus obj.entities's 200.)
As a consequence, the game had to use a separate tracking variable,
obj.nentity, because obj.entities.size() would just report 200, instead
of the actual amount of entities. Needless to say, having to check for
`active` and use `obj.nentity` is a bit error-prone, and it's messier
than simply using the std::vector the way it was intended. Also, this
resulted in a hard limit of 200 entities, which custom level makers ran
into surprisingly quite often.
2.3 comes along, and removes the whole system. Now, std::vectors are
properly being used, and obj.entities.size() reports the actual number
of entities in the vector; you no longer have to check for `active` when
dealing with entities of any sort.
But there was one previous behavior of 2.2 that this system kind of
forgets about - namely, the ability to have holes in between entities.
You see, when an entity got disabled in 2.2 (which just meant turning
its `active` off), the indices of all other entities stayed the same;
the indice of the entity that got disabled stays there as a hole in the
array. But when an entity gets removed in 2.3 (previous to this patch),
the indices of every entity afterwards in the array get shifted down by
one. std::vector isn't really meant to be able to contain holes.
Do the indices of entities and blocks matter? Yes; they determine the
order in which entities and blocks get evaluated (the highest indice
gets evaluated first), and I had to fix some block evaluation order
stuff in previous PRs.
And in the case of entities, they matter hugely when using the
recently-discovered Arbitrary Entity Manipulation glitch (where crewmate
script commands are used on arbitrary entities by setting the `i`
attribute of `scriptclass` and passing invalid crewmate identifiers to
the commands). If you use Arbitrary Entity Manipulation after destroying
some entities, there is a chance that your script won't work between 2.2
and 2.3.
The indices also still determine the rendering order of entities
(highest indice gets drawn first, which means lowest indice gets drawn
in front of other entities). As an example: let's say we have the player
at 0, a gravity line at 1, and a checkpoint at 2; then we destroy the
gravity line and create a crewmate (let's do Violet).
If we're able to have holes, then after removing the gravity line, none
of the other indices shift. Then Violet will be created at indice 1, and
will be drawn in front of the checkpoint.
But if we can't have holes, then removing the gravity line results in
the indice of the checkpoint shifting down to indice 1. Then Violet is
created at indice 2, and gets drawn behind the checkpoint! This is a
clear illustration of changing the behavior that existed in 2.2.
However, I also don't want to go back to the `active` system of having
to check an attribute before operating on an entity. So... what do we
do to restore the holes?
Well, we don't need to have an `active` attribute, or modify any
existing code that operates on entities. Instead, we can just set the
attributes of the entities so that they naturally get ignored by
everything that comes into contact with it. For entities, we set their
invis to true, and their size, type, and rule to -1 (the game never uses
a size, type, or rule of -1 anywhere); for blocks, we set their type to
-1, and their width and height to 0.
obj.entities.size() will no longer necessarily equal the amount of
entities in the room; rather, it will be the amount of entity SLOTS that
have been allocated. But nothing that uses obj.entities.size() needs to
actually know the amount of entities; it's mostly used for iterating
over every entity in the vector.
Excess entity slots get cleaned up upon every call of
mapclass::gotoroom(), which will now deallocate entity slots starting
from the end until it hits a player, at which point it will switch to
disabling entity slots instead of removing them entirely.
The entclass::clear() and blockclass::clear() functions have been
restored because we need to call their initialization functions when
reusing a block/entity slot; it's possible to create an entity with an
invalid type number (it creates a glitchy Viridian), and without calling
the initialization function again, it would simply not create anything.
After this patch is applied, entity and block indices will be restored
to how they behaved in 2.2.
Ever since 2.0, the colors of some of the Time Trial trophies in the
Secret Lab don't correspond to the crewmate of the given level. The
trophy for the Tower uses Victoria's color, and the Lab trophy uses
Vermilion's color. The Space Station 2 trophy uses Viridian's color, and
the Final Level trophy uses Vitellary's color.
This doesn't appear to be intentional, and it would be odd if it was,
since this game matches the colors everywhere else (each zone on the map
is colored with their respective crewmate in mind, for instance). Also,
the Lab trophy has the sad expression, which is Victoria's trait - it
would be weird if this was intended for Vermilion instead.
But the biggest piece of evidence that this was unintentional is the
corresponding comment for each color in Graphics::setcol(). It mislabels
yellow as cyan, cyan as yellow, blue as red, and red as blue.
To fix this, I simply have to set the correct color for each trophy in
case 25 of entityclass::createentity(). I could fix it in
Graphics::setcol() itself, but custom levels might depend on those
certain colors being the way they are, so it's a safer bet to just fix
it in the trophy creation case itself.
The diff of this might look weird. Even though all I'm doing is changing
some value assignments around, it looks like the "patience" algorithm
thinks I'm moving a whole case of the trophy switch-case around.
This prevents issues when calling std::abs with a float on some older
compilers. While it would normally be promoted to an int, std::abs is
special due to being overloaded despite being a C function. This can
cause errors due to the compiler being unable to find a float overload.
SDL_abs doesn't have this problem, since it's a normal C function.
This check is clearly meant for destroying the factory clouds in the
room "Level Complete!" in the main game, but it covers all rooms on row
8, instead of only (13,8). Adding an x-room check restricts this
behavior to only (13,8).
Trinket9 reported that this weird behavior of destroying specifically
above y-position 60 was undesirable, since they were creating an enemy
with this `behave` in a room on row 8 and it kept disappearing
instantly.
cppcheck said: "Logical disjunction always evaluates to true".
Yes. Yes it does. Whoops. I learned how to specify ranges like this in
high school math and still screw it up...
Scripting crewmates apparently have a specific hardcoded rule in their
follow-player code that makes it so if they're in (10,5) and are to the
left of the line x=155, they will refuse to continue following the
player. This was clearly done to make it so Vitellary in the main game
wouldn't overlap the teleporter, and that was clearly done to make it so
it wouldn't look like he would go behind the teleporter, which would
look weird (I also noticed this in #513).
I stumbled across this code and thought that just like other weird
main-game code that shouldn't apply in custom levels (#136, #137, #144),
this should be fixed, too.
While my previous commit fixes the glitchy y-position when you get stuck
inside a conveyor, I noticed that getting inside a conveyor seems to
always push the player out, despite conveyors sharing the same code with
moving platforms, which has code to temporarily disable their own
collision when the player gets stuck inside them, so that the player
DOESN'T get pushed out.
Well, it turns out that the reason this happens is because conveyors in
a room that get placed during mapclass::loadlevel() get tile 1 placed
underneath them. This is mostly so moving platforms will collide with
them, because otherwise platforms don't collide with other platforms,
and a conveyor is considered a platform.
This means that a conveyor without any tiles behind it will simply get
the player stuck if they get inside it, and the player won't be pushed
out. This is bad, because conveyors don't move, so they'll be stuck
there forever until they press R (or save, quit, and load). This
situation doesn't come up in the main game, but it COULD come up in
custom levels that use the internal createentity() command to create
conveyors that don't have any tiles behind them.
It seems good to fix this as well, while we're at it fixing conveyor
physics, so I'm fixing this as well.
I was investigating a desync in my Nova TAS, and it turns out that
the gravity line collision functions check for the `oldxp` and `oldyp`
of the player, i.e. their position on the previous frame, along with
their position on the current frame. So, if the player either collided
with the gravity line last frame or this frame, then the player collided
with the gravity line this frame.
Except, that's not actually true. It turns out that `oldxp` and `oldyp`
don't necessarily always correspond to the `xp` and `yp` of the player
on the previous frame. It turns out that your `oldyp` will be updated if
you stand on a vertically moving platform, before the gravity line
collision function gets ran. So, if you were colliding with a gravity
line on the previous frame, but you got moved out of there by a
vertically moving platform, then you just don't collide with the gravity
line at all.
However, this behavior changed in 2.3 after my over-30-FPS patch got
merged (#220). That patch took advantage of the existing `oldxp` and
`oldyp` entity attributes, and uses them to interpolate their positions
during rendering to make everything look real smooth.
Previously, `oldxp` and `oldyp` would both be updated in
`entityclass::updateentitylogic()`. However, I moved it in that patch to
update right before `gameinput()` in `main.cpp`.
As a result, `oldyp` no longer gets updated whenever the player stands
on a vertically moving platform. This ends up desyncing my TAS.
As expected, updating `oldyp` in `entityclass::movingplatformfix()` (the
function responsible for moving the player whenever they stand on a
vertically moving platform) makes it so that my TAS syncs, but the
visuals are glitchy when standing on a vertically moving platform. And
as much as I'd like to get rid of gravity lines checking for whether
you've collided with them on the previous frame, doing that desyncs my
TAS, too.
In the end, it seems like I should just leave `oldxp` and `oldyp` alone,
and switch to using dedicated variables that are never used in the
physics of the game. So I'm introducing `lerpoldxp` and `lerpoldyp`, and
replacing all instances of using `oldxp` and `oldyp` that my over-30-FPS
patch added, with `lerpoldxp` and `lerpoldyp` instead.
After doing this, and applying #503 as well, my Nova TAS syncs after
some minor but acceptable fixes with Viridian's walkingframe.
This commit restores the evaluation order of moving platforms and conveyors to
be what it was in 2.2. The evaluation order changed in 2.3 after the patchset
to improve the handling of the `obj.entities` and `obj.blocks` vectors (#191).
By evaluation order, I'm talking about the order in which platforms and
conveyors will be evaluated (and thus will take priority) if Viridian stands
on both a conveyor or platform at once, and they either have different speeds
or are pointing in different directions. Nowhere in the main game is there a
place where you can stand on two different conveyors/platforms at once, so
this is solely within the territory of custom levels, which is my specialty.
So what caused this evaluation order to change? Well, every moving platform
and conveyor in the game is actually made up of two objects: an entity, and a
block. The entity is the part that moves around, and the block is the part
that actually has the collision.
But if the entity is the part that moves around, and entities and blocks are
in entirely separate vectors, how is the block part going to move along with
it? Well, maybe you'd guess some sort of unique ID system, but spend some time
digging around the code and you won't find any trace of any (there's no
attribute on an entity to store such an ID, for starters).
Instead, what the game does is actually remove all blocks that coincide with
the exact top-left corner of the entity, and then create a new one. Destroying
and creating blocks like this all the time is hugely wasteful, but hey, it
worked.
So why did the evaluation order change in 2.3? Well, to understand that,
you'll need to understand 2.2's `active` system. Instead of having an object
be real simply by virtue of it existing, 2.2 had this system where the object
was only real if it had its `active` attribute set to true. In other words,
you would be looking at a fake object that didn't actually exist if its
`active` attribute was false.
On the surface, this doesn't seem that bad. But this can lead to "holes" in a
given vector of objects. A hole is simply an inactive object neighbored by
active objects (or the inactive object could be the first one in the vector,
but then have an active object immediately following it).
If you have a vector of 3 objects, all of them active, then removing the
second one will result in the vector containing an active object, followed by
an inactive object, followed by an active one. However, since the switch to
more properly use vectors instead of relying on this `active` system, there's
no longer any way for holes to exist in a vector. Properly removing an object
from a vector will just shift the rest of the objects down, so if we remove
the second object after the vector fix, then this will simply move the third
object into the slot of where the second object used to be.
So, what happens if you destroy a block and then create a new one in the
`active` system? Let's say that your `obj.blocks` looks like this, and here
I'm denoting each block by writing out its coordinates:
[30,60] [70,90] [80,100]
and that you want to update the position of the second one, because the entity
that that blocks belongs to has been updated. Okay, so, you delete that block,
which then makes things look like this:
[30,60] [-] [80,100]
and then afterwards, you create a new block with the updated position,
resulting in this:
[30,60] [74,90] [80,100]
Since `entityclass::createblock()` will find the first block slot that has a
false `active` attribute, it puts the new object in the same slot as the old
one. What has been essentially done here is that the slot of the block has
basically been reserved for the new block with the new position. Here, the
evaluation order of each block will stay the same.
But then 2.3 comes along and changes things up. So we start with an
`obj.blocks` like this again:
[30,60] [70,90] [80,100]
and we want to update the second block, like before. So we remove the second
block, resulting in this:
[30,60] [80,100]
It should be obvious that unlike before, where the third block stayed in the
third slot, the third block has now been moved to the second slot. But
continuing on; we are now going to create the new block with its updated
position, resulting in this:
[30,60] [80,100] [70,90]
At this point, we can see that the evaluation order of these blocks has been
changed due to the fact that the third block has now been moved to the slot
that was previously the slot of the second block.
So what can we do about this? Well, we can basically emulate what VVVVVV did
in 2.2, which is disable a block without actually removing it - except I'm not
going to reintroduce an `active` attribute or anything. I'll disable the
collision of all blocks at a certain position by setting their widths and
heights to 0, and then re-enable them later by finding the first block at that
same position, updating its position, and re-assigning its width and height
again.
The former is what `entityclass::nocollisionat()` does; the latter is what
`entityclass::moveblockto()` does. The former mimicks turning off the `active`
attribute of all blocks sharing a certain top-left corner; the latter mimicks
creating a new block - and it will only do this for one block, because
`entityclass::createblock()` in 2.2 only looked for the first block with a
false `active` attribute.
Now, some quirks relied on the previous behavior of destroying and creating
blocks, but all of these quirks have been preserved with the way I implemented
this fix.
The first quirk is that platforms passing through 0,0 will destroy all spike
hitboxes, script boxes, activity zones, and one-way hitboxes in the room. The
hitboxes of moving platforms, disappearing platforms, 1x1 quicksand, and
conveyors will not be affected.
This is a consequence of the fact that the former group uses the `x` and `y`
of their `rect`, while the latter group uses the `xp` and `yp` attributes. So
the `xp` and `yp` of the former are both 0. Meaning, a platform passing
through 0,0 destroys them all.
Having these separate coordinates seems like an artifact from the Flash days.
(And furthermore, there's an unused `x` and `y` attribute on all blocks,
making for technically three separate sets of coordinates! This should
probably be cleaned up, except for what I'm about to say...) But actually, if
you merge both sets of coordinates into one, this lets moving platforms
destroy script boxes and activity zones if it passes through the top-left
corner of them, which is probably far worse than the destruction being
localized to a specific coordinate that would never likely be reached
normally.
This quirk is preserved just fine without any special-casing, because instead
of destroying all blocks at 0,0, they just get disabled, which does the same
job. This quirk seems trivial to fix if I made it so that the position of a
platform's block was updated instantaneously instead of having one step to
disable it and another step to re-enable it, but I aim to preserve as much
quirks as possible.
The second quirk is that a moving platform passing through the top-left corner
of a disappearing platform or 1x1 quicksand will destroy the block of that
disappearing platform. This is because, again, when a moving platform updates,
it destroys all blocks at its previous position, not just only one block. This
is automatically preserved because this commit just disables the block of the
disappearing platform instead of removing it. Just like the last one, this
quirk seems extremely trivial to fix, and this time by simply making it so
`entityclass::nocollisionat()` would have a `break` statement, i.e. only
disabling the first block it finds instead of all blocks it finds, but I want
to keep all quirks that are possible to keep.
The last quirk is that, apparently, in order to prevent pushing the player
vertically out of a moving platform if they get inside of one, the game
destroys the block of the moving platform. If I had missed this edge case,
then the block would've been destroyed, leaving the moving platform with no
collision. But I caught it in my testing, so the block gets disabled instead
of destroyed. Also, it seems obtuse for those who don't understand why a
platform's block gets destroyed or disabled whenever the player collides with
it in `entityclass::collisioncheck()`, so I've put up a comment documenting it
as well.
The different platform evaluation order desyncs my Nova TAS, but after
applying this patchset and #504, my TAS syncs fine (save for the different
walkingframe from starting immediately on the ground instead of in the air
(#502), but that's minor and can be easily fixed).
I've attached a test level to the pull request for this commit (#503) to
demonstrate that this patchset not only fixes platform evaluation order, but
preserves some bugs and quirks with the existing block system.
The first room demonstrates the fixed platform evaluation order, by stepping
on the conveyors that both point into each other. In 2.2, Viridian will move
to the right of the background pillar, but in 2.3, Viridian will move to the
left of the pillar. However, after applying this patch, Viridian will now move
to the right of the pillar once again.
The second room demonstrates that the platform-passing-through-0,0 trick still
works (as explained above).
The last room demonstrates that platforms passing through the top-left corners
of disappearing platforms or 1x1 quicksand will remove the blocks of those
entities, causing Viridian to immediately pass through them. This trick is
still preserved after my patchset is applied.
It seems like the start point of a custom level and all checkpoints in
the game end up putting your spawn point one pixel away from the surface
it touches, which seems like an oversight. I'm going to enforce some
consistency here and make it so that all spawn points, whenever you
start from a start point or a checkpoint, will always be correctly
positioned flush with the surface they're standing on, and not one pixel
more or less than that.
So, 77a636509b fixed the fact that you
only got 1 frame of onground/onroof when standing on a vertical moving
platform, but removing those lines entirely means that it takes 1 frame
before the onground/onroof of 2 actually takes effect. This desyncs my
Nova TAS, so it seems important to fix.
The onroof/onground attributes are used to determine if the player is
standing on a surface and is eligible to flip. Most notably, it is an
integer and not a boolean, and it starts at 2, giving the player 2
frames to edge-flip, i.e. they can still flip 2 frames after walking off
an edge.
However, these attributes are unnecessarily reassigned in
movingplatformfix() (which is the function that deals exclusively with
vertically-moving platforms; horizontal moving platforms get their own
hormovingplatformfix()). Whoever wrote this misunderstood what
onroof/onground meant; they thought that they were booleans, and so set
them to true, instead of the proper value of 2. This ends up setting
onroof/onground to 1 instead of 2, causing a discrepancy with vertical
moving platforms and the rest of the surfaces in the game.
The bigger mistake here is duplicating code that never needed to be
duplicated. The onroof/onground assignment in gamelogic() works
perfectly fine for vertical moving platforms. Indeed, after testing it
with libTAS, I can confirm that removing the duplicate assignments
restores being able to edge-flip off of moving platforms with 2 frames
of leeway, instead of only 1 frame. It also doesn't change how long it
takes for the onroof/onground to get set when the player is recognized
as standing on a vertically-moving platform, either.
And so, it's better to not duplicate this code, because when you
duplicate it you run the risk of making a mistake, as I just
demonstrated.
By "unnecessary qualifiers to self", I mean something like using the
'game.' qualifier for a variable on the Game class when you're inside a
function on the Game class itself. This patch is to enforce consistency
as most of the code doesn't have these unnecessary qualifiers.
To prevent further unnecessary qualifiers to self, I made it so the
extern in each header file can be omitted by using a define. That way,
if someone writes something referring to 'game.' on a Game function,
there will be a compile error.
However, if you really need to have a reference to the global name, and
you're within the same .cpp file as the implementation of that object,
you can just do the extern at the function-level. A good example of this
is editorinput()/editorrender()/editorlogic() in editor.cpp. In my
opinion, they should probably be split off into their own separate file
because editor.cpp is getting way too big, but this will do for now.
This is a refactor that simply moves all temporary variables off of
entityclass, and makes it so they are no longer global variables. This
makes the resulting code easier to understand as it is less entangled
with global state.
These attributes were:
- colpoint1
- colpoint2
- tempx
- tempy
- tempw
- temph
- temp
- temp2
- tpx1
- tpy1
- tpx2
- tpy2
- temprect
- temprect2
- x (actually unused)
- dx
- dy
- dr
- px
- py
- linetemp
- activetrigger
- skipblocks
- skipdirblocks
Most of these attributes were assigned before any of the times they were
used, so it's easy to prove that ungloballing them won't change any
behaviors. However, dx, dy, dr, and skipblocks are a bit more tricky to
analyze. They relate to blocks, with dx, dy, and dr more specifically
relating to one-way tiles. So after some testing with the quirks of
one-way tiles, it seems that the jankiness of one-way tiles haven't
changed at all, either.
Unfortunately, the attribute k is clearly used without being assigned
beforehand, so I can't move it off of entityclass. It's the same story
with the attribute k that Graphics has, too.
For some reason, the variable `k` is on entityclass and gets mutated in
createentity() and createblock(). Then updateentities() uses it without
checking if it's valid, because either `k` or the size of `entities`
could have changed in the meantime. To fix any potential undefined
behavior, these bounds checks should be added.
The entity getters I'm referring to are entityclass::getscm(),
entityclass::getlineat(), entityclass::getcrewman(), and
entityclass::getcustomcrewman().
Even though the player should always exist, and the player should always
be indice 0, I wouldn't want to make that assumption. I've been wrong
before.
Also, these functions returning 0 lull you into a false sense of
security. If you assume that commands using these functions are fine,
you'll forget about the fact that `i` in those commands could be
potentially anything, given an invalid argument. In fact, it's possible
to index createactivityzone(), flipgravity(), and customposition()
out-of-bounds by setting `i` to anything! Well, WAS possible. I fixed it
so now they can't.
Furthermore, in the game.scmmoveme block in gamelogic(), obj.getplayer()
wasn't even checked, even though it's been checked in all other places.
I only caught it just now because I wanted to bounds-check all usages of
obj.getscm(), too, and that game.scmmove block also used obj.getscm()
without bounds-checking it as well.
When this is done, there is potential for a mistake to occur when
writing out the bounds check, which is eliminated when using the macro
instead. Luckily, this doesn't seem to have happened, but what's even
worse is I hardcoded 400 instead of using SDL_arraysize(ed.level), so if
the size of ed.level the bounds checks would all be wrong, which
wouldn't be good. But that's fixed now, too.
This is because if they are manually written out, they are more likely
to contain mistakes.
In fact, after further review, there are several functions with
incorrect manually-written bounds checks:
* entityclass::entitycollide()
* entityclass::removeentity()
* entityclass::removeblock()
* entityclass::copylinecross()
* entityclass::revertlinecross()
All of those functions forgot to do 'greater than or equal to' instead
of 'greater than' when comparing against the size of the vector. So they
were erroneous. But they are now fixed.
It's better to do INBOUNDS_VEC(i, obj.entities) instead of 'i > -1'.
'i > -1' is used in cases like obj.getplayer(), which COULD return a
sentinel value of -1 and so correct code will have to check that value.
However, I am now of the opinion that INBOUNDS_VEC() should be used and
isn't unnecessary.
Consider the case of the face() script command: it's not enough to check
i > -1, you should read the routine carefully. Because if you look
closely, you'll see that it's not guaranteed that 'i' will be initialized
at all in that command. Indeed, if you call face() with invalid
arguments, it won't be. And so, 'i' could be something like 215, and
that would index out-of-bounds, and that wouldn't be good. Therefore,
it's better to have the full bounds check instead of checking only one
bounds. Many commands are like this, after some searching I can also
name position(), changemood(), changetile(), changegravity(), etc.
It also makes the code more explicit. Now you don't have to wonder what
-1 means or why it's being checked, you can just read the 'INBOUNDS' and
go "oh, that checks if it's actually inbounds or not".
Since there's an INBOUNDS_ARR() macro, it's much better to specify the
macro for the vector is a macro for the vector, to avoid confusion.
All usages of this macro have been renamed accordingly.
Stuck prevention (pushing the player/supercrewmate out if they are
inside a wall) has been factored out into its own function, so it's no
longer copy-pasted but slightly tweaked just for the supercrewmate.
Instead of having two separate functions to move entities along vertical
moving platforms, one for the player and one for the supercrewmate, they
have been consolidated into one function.
So, I was staring at VVVVVV code one day, as I usually do, and I noticed
that warp lines had this curious code in entityclass::updateentities()
that set their statedelay to 2, and I thought, hm, maybe the pre-2.1
warp line bypass is caused by this statedelay. And, it doesn't seem like
this is the primary code used to detect if the player collides with warp
lines, the actual code is commented with "Rewritten system for mobile
update" and bolted-on in gamelogic() instead of properly being in
entityclass::entitycollisioncheck().
So, after getting tripped up on the misleading indentation of that
"Rewritten system" block, I removed the rewritten system, re-added
collision detection for rule 7 (horizontal warp lines), and after
checking the resulting behavior, it appears to be nearly identical to
that of warp lines in 2.0.
You see, if you use warp lines to flip up from the top of the screen
onto the bottom of the screen, close to the edge of the bottom of the
screen, Viridian's head will display on the top of the screen in 2.0. In
2.1 and later, this doesn't happen, confirming that my theory is
correct. I also performed warp line bypass multiple times in 2.0 and
with my restored code, and it is pretty much the exact same behavior.
So now, the pre-2.1 warp line bypass glitch has been re-enabled in
glitchrunner mode.
I noticed that if I have a large amount of entities in the room, the
game starts to freeze and one frame would take a very long time. I
identified an obvious cause of this, which is that the entity collision
checking in entityclass::entitycollisioncheck() is O(n²), n being the
number of entities in the room.
But it doesn't need to be O(n²). The only entities you need to check
against all other entities are the player and the supercrewmate. You
don't need to "test entity to entity" if 99% of the pairs of entities
you're checking don't involve the player or supercrewmate.
How do we make it O(n)? Well, just hoist the rule 0 and type 14 checks
out of the inner for-loop. That way, the inner for-loop won't be
unconditionally ran, meaning that in most cases it will always be O(n).
However, if you start having large amounts of duplicate player or
supercrewmate entities (I don't know why you would), it would start
approaching O(n²), but I feel like that's fair in that case. But most of
the time, it will be O(n).
So that's how collision checking is now O(n) instead.
This makes it so the fix for crewmates' drawframes being wrong for
1-frame is fixed for all crewmates regardless of when they get created.
Sure, crewmates created in mapclass::loadlevel() have their drawframes
fixed there, but for crewmates that get created from scripting (such as
Violet when gotorooming to the Ship teleporter room after Space Station
1), this fix doesn't apply to them. But now it does, and Violet will no
longer be facing the wrong way for 1 frame when teleporting to the Ship
teleporter room in the Space Station 1 Level Complete cutscene.
If the player is stuck in a wall (which shouldn't happen in the first
place), their sprite would always default to being flipped, even if they
were unflipped.
Being stuck in a wall is characterized by having both positive onfloor
and onground.
Some levels rely specifically on the fact that certain script boxes are
loaded using gamestates, instead of directly loading the script and
bypassing the gamestate system. Then weird things could happen. This
restores compatibility with those levels.
mapclass::twoframedelayfix() doesn't need to be updated because the
point of that function is to bypass the gamestate system entirely
anyways.
This moves the teleporter, activity prompt, and trophy text "don't draw"
conditionals to the part where the game checks collision with them,
instead of whenever the game draws them.
This makes it so that the game smoothly does the fade-in/fade-out
animation instead of suddenly stopping rendering them whenever their
"don't draw" conditions apply. Now, the "Press ENTER to activate
terminal" prompt will no longer suddenly disappear whenever you activate
one, and the "- Press ENTER to Teleport -" prompt will smoothly fade
back in after teleporting, instead of suddenly popping in on screen.
Including a header file inside another header file means a bunch of
files are going to be unnecessarily recompiled whenever that inner
header file is changed. So I minimized the amount of header files
included in a header file, and only included the ones that were
necessary (system includes don't count, I'm only talking about includes
from within this project). Then the includes are only in the .cpp files
themselves.
This also minimizes problems such as a NO_CUSTOM_LEVELS build failing
because some file depended on an include that got included in editor.h,
which is another benefit of removing unnecessary includes from header
files.
There were many different ways I could've fixed it, but one thing that
stood out to me was the fact that touching the teleporter wasn't
guaranteed to set its onentity to 0, even though it should be. So now,
every time Viridian touches the teleporter, the teleporter's onentity
will be set to 0, and thus there's no chance of the teleporter
interrupting its own teleport animation and softlocking the game.
We should still do what I suggested in #391, namely setting
game.hascontrol to true if the game is in gamestate 0 and script.running
is false, and also always allowing Esc/Enter to be pressed regardless of
game.hascontrol. But this softlock is fixed now.
Fixes#391.
Instead of using gamestates, just directly use the 'script' attribute of
a script box if it is non-empty.
This is accomplished by having to return the index of the block that the
player collides with, so callers can inspect the 'script' attribute of
the block themselves, and do their logic accordingly.
To avoid going through gamestates, we'll need to carry the name of the
script on the script box itself. And to do that, we'll need to set the
'script' attribute of script boxes when translating edentities into real
entities in custom levels.
I ran the game through cppcheck and it spat out a bunch of member
attributes that weren't being initialized. So I initialized them.
In the previous version of this commit, I added constructors to
GraphicsResources, otherlevelclass, labclass, warpclass, and finalclass,
but flibit says this changes the code flow enough that it's risky to
merge before 2.4, so I got rid of those constructors, too.
Since they're always fixed-size, they don't need to be dynamically-sized
vectors.
entityclass::customcrewmoods is now a proper bool instead of an int now,
and I replaced the hardcoded constant 6 with a static const int Game
attribute to make it easier to change.
Their drawframe needs to be incremented by 2 instead of 1, because
they're double-sized.
Animation type 3 is used by the cloud emitter in The Solution is
Dilution, animation type 6 is used by the radar dish in Comms Relay.
Animation type 4 is used by the maverick bus in B-B-B-Busted, but it's
not noticeable since it spawns offscreen. This bug would cause all of
those entities to appear incorrectly for the deltaframes between the
tick the room got loaded and the next tick after that.
This is noticeable in flibit's tweet showing off my over-30-FPS patch:
https://twitter.com/flibitijibibo/status/1273983014930993153
The only reason why gray Warp Zone entities were green originally was
because there is a giant concatenated list of tileset+tilecol
combinations, and by using tileset 3 tilecol 6 you're using the entry
of tileset 4 tilecol 0, which is the green Ship tileset.
So without interfering with the green Ship tileset's entry, I've decided
that the best thing to do is to just add special cases. The enemy color
was easy enough to fix. The platform color was also easy to fix.
However, there exist no existing textures for gray conveyors, so at that
point I decided to just tint the existing green one gray, and then I did
the same for platforms.
This patch is very kludge-y, but at least it fixes a semi-noticeable
visual issue in custom levels that use internal scripts to spawn
entities when loading a room.
Basically, the problem here is that when the game checks for script
boxes and sets newscript, newscript has already been processed for that
frame, and when the game does load a script, script.run() has already
been processed for that frame.
That issue can be fixed, but it turns out that due to my over-30-FPS
game loop changes, there's now ANOTHER visible frame of delay between
room load and entity creation, because the render function gets called
in between the script being loaded at the end of gamelogic() and the
script actually getting run.
So... I have to temporary move script.run() to the end of gamelogic()
(in map.twoframedelayfix()), and make sure it doesn't get run next
frame, because double-evaluations are bad. To do that, I have to
introduce the kludge variable script.dontrunnextframe, which does
exactly as it says.
And with all that work, the two-frame (now three-frame) delay is fixed.
What happens here is that the entity gets created and then gets
immediately updated on the next frame, but there's no time for their
walkingframe of 0 to be rendered, so it'll look like they have just
started with walkingframe 1. However in the delta-timestep rendering
it'll render with walkingframe 0. So we need to fix their drawframe and
increment it when creating them.
This is because their oldxp wasn't being updated when they move (or
rather, teleport) and wrap around the screen.
These enemies are ZZT centipedes, but they're referred to as ASCII
snakes in comments in the code.
Okay, so the problem here is that Graphics::setcol() is called right
before a sprite is drawn in a render function, but render functions are
done in deltatime, meaning that the color of a sprite keeps being
recalculated every time. This only affects sprites that use fRandom()
(the other thing that can dynamically determine a color is help.glow,
but that's only updated in the fixed-timestep loop), but is especially
noticeable for sprites that flash wildly, like the teleporter, trinket,
and elephant.
To fix this, we need to make the color be recalculated only in the
fixed-timestep loop. However, this means that we MUST store the color of
the sprite SOMEWHERE for the delta-timesteps to render it, otherwise the
color calculation will just be lost or something.
So each entity now has a new attribute, `realcol`, which is the actual
raw color used to render the sprite in render functions. This is not to
be confused with their `colour` attribute, which is more akin to a color
"ID" of sorts, but which isn't an actual color.
At the end of gamelogic(), as well as when an entity is first created,
the `colour` is given to Graphics::setcol() and then `realcol` gets set
to the actual color. Then when it comes time to render the entity,
`realcol` gets used instead.
Gravitron squares are a somewhat tricky case where there's technically
TWO colors for it - one is the actual sprite itself and the other is the
indicator. However, usually the indicator and the square aren't both
onscreen at the same time, so we can simply switch the realcol between
the two as needed.
However, we can't use this system for the sprite colors used on the
title and map screen, so we'll have to do something else for those.
Just to make sure it's extra smooth. Not that it will be noticeable, and
you can't access the Secret Lab in slowmode without modifying the game,
but it's nice to have this.
This has to be done in order to fix rendering when on a conveyor or
moving platform and actively moving with or against it. Pretty sure this
shouldn't break anything, oldxp/oldyp is mostly visual after all (and by
the time it's used for gravity line collision checking,
updateentitylogic() would've already gotten around to it anyway).
Incidentally, this also fixes a jitter that would occur if you were
moving at the time you died or collected a trinket or custom crewmate,
due to the game temporarily freezing and either doing deathsequence or
completestop.
This fixes entities being drawframe 0 for 1 frame when being first
created. Incidentally, this also fixes entities created during
completestop being the player sprite, too, which is something not many
people notice.
This prevents undefined behavior because we use oldxp/oldyp to do linear
interpolation.
It's also initialized in entclass::entclass(), just to be sure. And I've
deduplicated the regular xp/yp initialization in createentity(), too.
If a trinket or crewmate ID is out-of-bounds, it will not be created.
This is not only because the `collect`/`customcollect` check in
entityclass::createentity() would then be out-of-bounds, but also
touching it would also be out-of-bounds, too.
Display trinkets will always be created if the ID is out-of-bounds.
Apparently some people (@AllyTally) have been creating display trinkets
with IDs of -1 in order to get a display trinket that always shows up,
which is rather horrifying. But it makes sense, there's a lot more
nonzero int values than there are the amount of int values that are
zero, so it's fairly likely that the `collect` check will always come up
to be true (nonzero). Also, it's more useful to be able to have a
display trinket that always shows up without having to collect a trinket
beforehand, than it is to have it not be created (because technically by
default, you're already in the world where you don't have it created).
Display trinkets still have their `para` set to their ID, though, and if
they managed to gain an `onentity` of 1, bad things could happen... So
just to be sure, I added INBOUNDS checks to crewmates and trinkets in
entityclass::updateentities() so no UB will happen if you collect a
crewmate/trinket with an out-of-bounds ID. Also, I de-duplicated the
`collect`/`customcollect` setting, too.
I tracked down all the functions that took in an entity's drawframe and
made sure that no matter what value an entity's drawframe was, the game
would never segfault.
To deal with using a different image file for Flip Mode, it looks like
copy-paste was used. This isn't exactly maintainable code. So I'm
replacing it with a reference that changes depending on if the game is
in Flip Mode or not, instead.
Removing the player entity has all sorts of nasty effects, such as
softlocking the game because many inputs require there to be a player
present, such as opening the quit menu.
The most infamous glitch to remove the player entity is the Gravitron
Fling, where the game doesn't see a gravity line at a specific
y-position in the current room, and when it moves the bottom gravity
line it moves the player instead. When the gravity line gets outside the
room, it gets destroyed, so if the player gets dragged outside the room,
they get destroyed, too. (Don't misinterpret this as saying anytime the
player gets dragged outside the room, they get destroyed - it's only the
Gravitron logic that destroys them.)
Also, there are many places in the code that use entity-getting
functions that have a fallback value of 0. If it was possible to remove
the player, then it's possible for this fallback value of 0 to index
obj.entities out-of-bounds, which is not good.
To fix this, entityclass::removeentity() is now a bool that signifies if
the entity was successfully removed or not. If the entity given is the
player (meaning it first checks if it's rule 0, just so in 99% of cases
it'll short-circuit and won't do the next check, which is if
entityclass::getplayer() says the indice to be removed is the player),
then it'll refuse to remove the entity, and return false.
This is a change in behavior where callers might expect
entityclass::removeentity() to always succeed, so I changed the
removeentity_iter() macro to only decrement if removing the entity
succeeded. I also changed entityclass::updateentities() from
'removeentity(i); return true;' to 'return removeentity(i);'.
obj.getplayer() can return -1, which can cause out-of-bounds indexing of
obj.entities, which is really bad. This was by far the most changes, as
obj.getplayer() is the most used entity-getting function that returns
-1, as well as the most-used function whose sentinel value goes
unchecked.
To deal with the usage of obj.getplayer() in mapclass::warpto(), I just
added general bounds checks inside that function instead of changing all
the callers.
Instead of using somewhat-obtuse for-loops to initialize or reset these
vectors, it takes up less lines of code and is clearer if we use
std::vector::resize() and std::vector::clear() instead.
We need to replace an "or" with an "and".
My best guess for this oversight happening was because of the weird
ordering. The code originally did "temp < 30" first and "temp > -30"
second instead of the other way around. With the weird ordering, it
becomes more natural to insert an "or" instead of an "and". So I swapped
around the ordering just for good measure.
This is also fixed in the mobile version.
Due to the previous commit, these will no longer be regularly taking in
out-of-bounds entity indices. Or at least they shouldn't, so I'm putting
in these print statements here on the off-chance that they do.
Otherwise, this would result in the game updating an entity twice, which
isn't good. This is most noticeable in the Gravitron, where many
Gravitron squares are created and destroyed at a time, and it's
especially noticeable during the part near the end of the Gravitron
where the pattern is two Gravitron squares, one at the top and bottom,
and then two Gravitron squares in the middle afterwards. The timing is
just right such that the top one of the two middle ones would be
misaligned with the bottom one of the two when a Gravitron square gets
outside the screen.
To do this, I changed entityclass::updateentities() into a bool, and
made every single caller check its return value. I only needed to do
this for the ones preceding updateentitylogic() and
entitymapcollision(), but I wanted to play it safe and be defensive, so
I did it for the disappearing platform kludge, as well as the
updateentities() within the updateentities() function.
The main ones to beware of here are entityclass::updateentities(),
entityclass::updateentitylogic(), and entityclass::entitymapcollision().
They would index out-of-bounds and thus commit Undefined Behavior if the
entity was removed in entityclass::updateentities(). And it would've
been fine enough if I only added bounds checks to those functions.
However, I decided to be a bit more defensive and play it safe, and
added bounds checks to ALL functions taking in not only an entity
indice, but also blocks and linecrosskludge indices.
It's treated like a bool anyway, so might as well make it one.
This also necessitates updating every single instance where it or an
element inside it is used, too.
game.trinkets is supposed to be correlated with obj.collect, however why
not just count obj.collect directly?
This turns game.trinkets into a function, game.trinkets(), which will
directly count the number of collected trinkets and return it. This will
fix a few corner cases where the number of trinkets can desync with the
actual collection statuses of trinkets.
In order to keep save compatibility with previous versions of VVVVVV,
the game will still write the <trinkets> variable. However, it will not
read the <trinkets> variable from a save file.
Whenever you collect a trinket, game.stat_trinkets gets updated (if
applicable) to signify the greatest amount of trinkets you have ever
collected in the game. However, custom levels shouldn't be able to
affect this, as their trinkets are not the same trinkets as the main
game.
Just like earlier, these are of the form
if (cond1) { if (cond2) { if (cond3) { thing; } } }
and are really annoying to read.
Also this removes the remnants of the 'active' system that have been
replaced with 'if (true)' conditionals in order to not add noise to the
diff.
This removes the variables obj.nblocks, as well as removing the 'active'
attribute from the block object. Now every block is guaranteed to be
real without having to check the 'active' variable.
Removing a block while iterating now uses the removeblock_iter() macro.
