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Author SHA1 Message Date
Misa
3ca7b09012 Fix regression: quick stopping changing drawframe
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.
2021-07-28 20:11:16 -04:00
Misa
63a60b11cc Split onground/onroof into visual and logical variables
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.
2021-03-21 02:55:42 -04:00
Misa
6a3a1fe147
Explicitly declare void for all void parameter functions (#628)
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.
2021-02-25 17:23:59 -05:00
Misa
3927bb9713 Fix entity and block indices after destroying them
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.
2021-02-16 19:31:23 -05:00
Misa
733d0dad80 Add entclass::ishumanoid()
"Humanoid" is just a word for "crewmate or player" but without having to
say "crewmate or player". This is just to make it so humanoids get drawn
after all other entities get drawn, meaning humanoids will be drawn on
top.
2020-11-03 13:31:56 -05:00
Misa
b8a4b4dfe7 Restore previous oldxp/oldyp variables in favor of lerpoldxp/lerpoldyp
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.
2020-10-11 16:19:26 -04:00
Misa
733cad723b Remove unused attributes from entclass
These attributes were `jumping` and `jumpframe`. Removal of unused
attributes makes reading the code easier.
2020-09-28 15:45:53 -04:00
Misa
b5ff65c84e Remove unnecessary includes from header files
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.
2020-07-19 21:37:40 -04:00
Misa
3699adec82 Fix, for in-GAMEMODE sprites, their colors updating too fast
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.
2020-06-19 09:05:48 -04:00
Misa
2cb90afbda Remove entclass::clear(), simplify entclass initializations
Previously there was an entclass::clear(), and initialization of an
entclass was done by calling clear() in order to not duplicate code. But
now there's no need for an entclass::clear(), and it is in fact unused
(just call entityclass::removeentity() instead), so I'm removing this
function.
2020-04-03 23:28:47 -04:00
Misa
b1b1474b7b Refactor entities and linecrosskludge to not use the 'active' system
This removes the variables obj.nentity and obj.nlinecrosskludge, as well
as removing the 'active' attribute from the entity class object. Now
every entity you access is guaranteed to be real and you don't have to
check the 'active' variable.

The biggest part of this is changing createentity() to modify a
newly-created entity object and push it back instead of already
modifying an indice in obj.entities.

As well, removing an entity now uses the new obj.removeentity() function
and removeentity_iter() macro.
2020-04-03 23:28:47 -04:00
Misa
ae84de2c7e Move entityclass::settreadmillcolour() to entclass::settreadmillcolour()
This moves settreadmillcolour() onto the entity object, so I can invoke
it independent of an indice in obj.entities.
2020-04-03 23:28:47 -04:00
Misa
f5a84d7972 Move entityclass::setenemyroom() to entclass::setenemyroom()
This moves the setenemyroom() function onto the entity object itself, so
I can more easily change all 'entities[k].' to 'entity.' in
entityclass::createentity() later.

Additionally, I've had to move the rn() macro from Entity.h to Ent.h, or
else entclass::setenemyroom() won't know what it is.
2020-04-03 23:28:47 -04:00
Misa
d4cffed176 Move entityclass::setenemy() to entclass::setenemy()
This moves the setenemy() function onto the entity object itself,
instead of having to give the indice of the entity in obj.entities. This
makes the code more object-oriented so later I can simply change all
'entities[k]' to 'entity.' in entityclass::createentity().
2020-04-03 23:28:47 -04:00
Ethan Lee
f7c0321b71 Hello WWWWWWorld! 2020-01-08 10:37:50 -05:00