vx/vy mean x-velocity and y-velocity... except here, where it seems like
they're used as extra parameters that do different things depending on
the entity. But it seems like at one point they were actually meant to
be the speed of the entity (this is the case for the unused decorative
particle entities), and then just never got renamed when they weren't.
The custom levels community named these two parameters meta1 and meta2
in the reference list of entities for the createentity() script command,
so that's what I'm naming them here. This will avoid confusion (I know
that some people reading this function have genuinely mistaken the vx/vy
for actually meaning x-velocity and y-velocity, simply because they were
named that way).
I have spelled out each overloaded version instead, and only the
overloads that are actually used - which just happens to be everything
except the 8-argument one. I don't want to deal with callers right now
(there are too many of them), so I'm not going to change the names that
the callers use, nor do I want to change the amount of arguments any
existing callers use right now - but we will have to deal with them in
one way or another when we move to C.
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).
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 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.
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.
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.
Okay, so basically here's the include layout that this game now
consistently uses:
[The "main" header file, if any (e.g. Graphics.h for Graphics.cpp)]
[blank line]
[All system includes, such as tinyxml2/physfs/utfcpp/SDL]
[blank line]
[All project includes, such as Game.h/Entity.h/etc.]
And if applicable, another blank line, and then some special-case
include screwy stuff (take a look at editor.cpp or FileSystemUtils.cpp,
for example, they have ifdefs and defines with their includes).
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.
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.
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.
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.
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);'.
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.
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.
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.
Not sure why this function is here. It makes sense if you know that the
game will only do certain moving platform things if you already have a
moving platform in the room, however apparently this function has
absolutely nothing to do with it.
This function's sole purpose was to make sure obj.nentity was in sync,
and that obj.nentity-1 pointed to the last 'active' entity in
obj.entities. But now that obj.nentity is removed and we use
obj.entities.size() instead, it is no longer necessary.
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.
Also when we switch everything to not use 'active', we'll need this
macro to remove entities while iterating forwards through the vector one
at a time.
Ok, once we switch everything over to not use the 'active' system, it's
easier to read removeentity(t) than it is to read
entities.erase(entities.begin() + t).
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.
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().
