891ca527f9
Believe it or not, there are still some remnants of the ActionScript
coding standards in the codebase! And one of them sometimes pops up
whenever an integer division happens.
As it so happens, it seems like division in ActionScript automatically
produces a decimal number. So to prevent that, the game sometimes
subtracts off the remainder of the number to be divided before
performing the division on it.
Thus, we get statements that look like
(a - (a % b)) / b
And probably more parentheses surrounding it too, since it would be
copy-pasted into yet another larger expression, because of course it
would.
`(a % b)` here is subtracting the remainder of `a` divided by `b`, using
the modulo operator, before it gets divided by `b`. Thus, the number
will always be divisible by `b`, so dividing it will mathematically not
produce a decimal number.
Needless to say, this is unnecessary, and very unreadable. In fact, when
I saw these for the first time, I thought they were overcomplicated
_modulos_, _not_ integer division! In C and C++, dividing an integer by
an integer will always result in an integer, so there's no need to do
all this runaround just to divide two integers.
To find all of these, I used the command
rg --pcre2 '(.+?).+?-.+?(?=\1).+?%.+?([\d]+?).+?\/.+?(?=\2)'
which basically matches expressions of the form 'a - a % b / b', where
'a' and 'b' are identical and there could be any characters in the
spaces.
|
||
|---|---|---|
| .. | ||
| src | ||
| .dockerignore | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CONTRIBUTORS.txt | ||
| Dockerfile | ||
| fixupMac.sh | ||
| icon.ico | ||
| icon.rc | ||
| README.md | ||
| version.cmake | ||
How to Build
VVVVVV's official desktop versions are built with the following environments:
- Windows: Visual Studio 2010
- macOS: Xcode CLT, currently targeting 10.9 SDK
- GNU/Linux: CentOS 7
The engine depends solely on SDL2 2.0.14+ and SDL2_mixer. All other dependencies are statically linked into the engine. The development libraries for Windows can be downloaded from their respective websites, Linux developers can find the dev libraries from their respective repositories, and macOS developers should compile and install from source (including libogg/libvorbis/libvorbisfile).
Steamworks support is included and the DLL is loaded dynamically, you do not need the SDK headers and there is no special Steam or non-Steam version. The current implementation has been tested with Steamworks SDK v1.46.
To generate the projects on Windows:
# Put your SDL2/SDL2_mixer folders somewhere nice!
mkdir flibitBuild
cd flibitBuild
cmake -A Win32 -G "Visual Studio 10 2010" .. -DSDL2_INCLUDE_DIRS="C:\SDL2-2.0.14\include;C:\SDL2_mixer-2.0.4\include" -DSDL2_LIBRARIES="C:\SDL2-2.0.14\lib\x86\SDL2;C:\SDL2-2.0.14\lib\x86\SDL2main;C:\SDL2_mixer-2.0.4\lib\x86\SDL2_mixer"
Note that on some systems, the SDL2_LIBRARIES list on Windows may need
SDL2/SDL2main/SDL2_mixer to have .lib at the end of them. The reason for this
inconsistency is unknown.
Also note that if you're using a Visual Studio later than 2010, you will need to
change the -G string accordingly; otherwise you will get a weird cryptic
error. Refer to the list below:
- VS 2012:
"Visual Studio 11 2012" - VS 2013:
"Visual Studio 12 2013" - VS 2015:
"Visual Studio 14 2015" - VS 2017:
"Visual Studio 15 2017" - VS 2019:
"Visual Studio 16 2019" - VS 2022:
"Visual Studio 17 2022"
To generate everywhere else:
mkdir flibitBuild
cd flibitBuild
cmake ..
macOS may be fussy about the SDK version. How to fix this is up to the whims of however Apple wants to make CMAKE_OSX_SYSROOT annoying to configure and retain each time Xcode updates.
Including data.zip
You'll need the data.zip file from VVVVVV to actually run the game! It's available to download separately for free in the Make and Play edition of the game. Put this file next to your executable and the game should run.
This is intended for personal use only - our license doesn't allow you to actually distribute this data.zip file with your own forks without getting permission from us first. See LICENSE.md for more details. (If you've got a project in mind that requires distributing this file, get in touch!)
A Word About Compiler Quirks
(Note: This section only applies to version 2.2 of the source code, which is the initial commit of this repository. Since then, much hard work has been put in to fix many undefined behaviors. If you're compiling the latest version of the source code, ignore this section.)
This engine is super fussy about optimization levels and runtime checks. In particular, the Windows version absolutely positively must be compiled in Debug mode, with /RTC enabled. If you build in Release mode, or have /RTC disabled, the game behaves dramatically different in ways that were never fully documented (bizarre softlocks, out-of-bounds issues that don't show up in tools like Valgrind, stuff like that). There are lots of things about this old code that could be cleaned up, polished, rewritten, and so on, but this is the one that will probably bite you the hardest when setting up your own build, regardless of platform.
We hope you'll enjoy messing with the source anyway!
Love, flibit