This macro is to make it so it won't be error-prone to write the
semi-confusing `(a % b + b) % b` statement, and you can just use an easy
macro instead.
Currently, the only places a positive modulo is needed is when switching
tilesets, enemies, and warp directions in the editor, as well as when
getting a tile in the tower, since towers just repeat themselves
vertically. Towers used this weird while-loop to sort of emulate a
modulo, which isn't half-bad, but is unnecessary, and I don't think any
compiler would recognize it as a modulo. (And if it's not optimized to a
proper modulo... what happens if the number being moduloed is really,
really big?)
There's really no reason for this simple multiplication plus division to
be in a lookup table. The compiler will optimize it faster than putting
it in a lookup table will, I'm sure.
This macro needs to be used because Clang is stupid and doesn't let you
use /* fallthrough */ comments like GCC does. However, if GCC is too old
(as is the case on CentOS 7), then it won't recognize __has_attribute
either.
FILESYSTEM_mountAssets() has a big comment describing the magic numbers
needed to grab FILENAME from a string that looks like
"levels/FILENAME.vvvvvv".
Instead of doing that (and having to write a comment every time the
similar happens), I've written a macro (and helper function) instead
that does the same thing, but clearly conveys the intent.
I mean, just look at the diff. Using VVV_between() is much better than
having to read that comment, and the corresponding SDL_strlcpy().
This function is simple - it takes a given buffer and its size, fills it
with a certain character, and null-terminates it. It's meant to be used
with freshly-created buffers, so we don't copy-paste code.
There's not really any reason for this function to use heap-allocated
strings. So I've refactored it to not do that.
I would've used SDL_strrstr(), if it existed. It does not appear to
exist. But that's okay.
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.
The current way "arrays" from XML files are loaded (before this commit
is applied) goes something like this:
1. Read the buffer of the contents of the tag using TinyXML-2.
2. Allocate a buffer on the heap of the same size, and copy the
existing buffer to it. (This is what the statement `std::string
TextString = pText;` does.)
3. For each delimiter in the heap-allocated buffer...
a. Allocate another buffer on the heap, and copy the characters from
the previous delimiter to the delimiter you just hit.
b. Then allocate the buffer AGAIN, to copy it into an std::vector.
4. Then re-allocate every single buffer YET AGAIN, because you need to
make a copy of the std::vector in split() to return it to the caller.
As you can see, the existing way uses a lot of memory allocations and
data marshalling, just to split some text.
The problem here is mostly making a temporary std::vector of split text,
before doing any actual useful work (most likely, putting it into an
array or ANOTHER std::vector - if the latter, then that's yet another
memory allocation on top of the memory allocation you already did; this
memory allocation is unavoidable, unlike the ones mentioned earlier,
which should be removed).
So I noticed that since we're iterating over the entire string once
(just to shove its contents into a temporary std::vector), and then
basically iterating over it again - why can't the whole thing just be
more immediate, and just be iterated over once?
So that's what I've done here. I've axed the split() function (both of
them, actually), and made next_split() and next_split_s().
next_split() will take an existing string and a starting index, and it
will find the next occurrence of the given delimiter in the string. Once
it does so, it will return the length from the previous starting index,
and modify your starting index as well. The price for immediateness is
that you're supposed to handle keeping the index of the previous
starting index around in order to be able to use the function; updating
it after each iteration is also your responsibility.
(By the way, next_split() doesn't use SDL_strchr(), because we can't get
the length of the substring for the last substring. We could handle this
special case specifically, but it'd be uglier; it also introduces
iterating over the last substring twice, when we only need to do it
once.)
next_split_s() does the same thing as next_split(), except it will copy
the resulting substring into a buffer that you provide (along with its
size). Useful if you don't particularly care about the length of the
substring.
All callers have been updated accordingly. This new system does not make
ANY heap allocations at all; at worst, it allocates a temporary buffer
on the stack, but that's only if you use next_split_s(); plus, it'd be a
fixed-size buffer, and stack allocations are negligible anyway.
This improves performance when loading any sort of XML file, especially
loading custom levels - which, on my system at least, I can noticeably
tell (there's less of a freeze when I load in to a custom level with
lots of scripts). It also decreases memory usage, because the heap isn't
being used just to iterate over some delimiters when XML files are
loaded.
This avoids an unnecessary copy of the input std::vector, since we don't
need to modify it for anything. This cuts down on unnecessary memory
operations.
Apart from the std::string, this function no longer uses the STL.
ss_toi() is a simple function - it converts the input into an int,
taking as many digits as possible until it reaches a non-digit
character, at which point it stops. It's trivial to implement this
without the STL.
I could've used Int() here, but that would've required copying the
string to a temporary buffer to insert a null-terminator (we can't just
use a pointer-and-length data type either, the string functions don't
operate like that - one disadvantage of C strings!). Instead, I decided
to implement my own conversion to int here, because I don't think the
way we humans write our Arabic numerals is going to change anytime soon.
Also, the std::string input is now passed by const reference, instead of
making a copy - cutting down on unnecessary memory operations.
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.
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.
If necessary, the caller can provide a fallback to be returned in case
the input given isn't a valid integer, instead of having to duplicate
the is_number() check.
This is simply a wrapper function around SDL_atoi(), because SDL_atoi()
could call libc atoi(), and whether or not invalid input passed into the
libc atoi() is undefined behavior depends on the given libc. So it's
safer to just add a wrapper function that checks that the string given
isn't bogus.
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).
These functions will only complain once if they receive an out-of-bounds
tile. And it's only once because these functions are called frequently
in rendering code.
A macro WHINE_ONCE() has been added in order to not duplicate code.
This ensures that endsWith() can be used outside of editor.cpp.
When leo60228 originally wrote endsWith(), it was static, but I asked
him on Discord just now and he more-or-less confirmed that it's fine if
it's not static. If it was static, it would be confined to
UtilityClass.cpp now instead!
Unlike, say, the scriptclass i/j/k stuff, these tempstrings are only
purely visual, and there's no known glitches to manipulate them anyway.
Thus I think it's safe to make this cleanup.
This commit makes `help`, `graphics`, `music`, `game`, `key`, `map`, and
`obj` essentially static global objects that can be used everywhere.
This is useful in case we ever need to add a new function in the future,
so we don't have to bother with passing a new argument in which means we
have to pass a new argument in to the function that calls that function
which means having to pass a new argument into the function that calls
THAT function, etc. which is a real headache when working on fan mods of
the source code.
Note that this changes NONE of the existing function signatures, it
merely just makes those variables accessible everywhere in the same way
`script` and `ed` are.
Also note that some classes had to be initialized after the filesystem
was initialized, but C++ would keep initializing them before the
filesystem got initialized, because I *had* to put them at the top of
`main.cpp`, or else they wouldn't be global variables.
The only way to work around this was to use entityclass's initialization
style (which I'm pretty sure entityclass of all things doesn't need to
be initialized this way), where you actually initialize the class in an
`init()` function, and so then you do `graphics.init()` after the
filesystem initialization, AFTER doing `Graphics graphics` up at the
top.
I've had to do this for `graphics` (but only because its child
GraphicsResources `grphx` needs to be initialized this way), `music`,
and `game`. I don't think this will affect anything. Other than that,
`help`, `key`, and `map` are still using the C++-intended method of
having ClassName::ClassName() functions.
