1
0
mirror of https://github.com/TerryCavanagh/VVVVVV.git synced 2024-06-28 15:38:30 +02:00
VVVVVV/desktop_version
Misa 8ba1325d0f Fix regression with wall stuck flipping behavior exactly reversed
The reason why the wall stuck flipping behavior happened in the first
place was because the code went like this:

    if (jumppressed)
    {
        if (onground && gravitycontrol == 0)
        {
            gravitycontrol = 1;
        }
        if (onroof && gravitycontrol == 1)
        {
            gravitycontrol = 0;
        }
    }

Basically, if you were both on ground and on a roof (i.e. stuck in a
wall), you would flip, but then due to code order and the fact that the
statement is not connected to the previous one, you would immediately
unflip afterwards. But if you were already flipped then the only path
that can be taken is to unflip you, since it's the statement that
appears last.

52fceb3f69 replaces the onground/onroof
conditionals with any_onground/any_onroof, so any player entity would
allow you to flip. But otherwise the code is the same. So is that the
problem?

No; tracing it through with GDB reveals that when you flip,
gravitycontrol is being set to 1, but never being set to 0. And it turns
out that's because any_onroof is not getting set. And that happens
because of another thing that 52fceb3f69
did - which was to set any_onground/any_onroof to true if indeed any
player entity was on ground or on a roof.

Unfortunately, the way Leo did it was to make the two statements
mutually exclusive - an 'if'-'else if' instead of two separate
statements. So a single entity could not mark both any_onground and
any_onroof as true (and the majority of the time, you will be a single
entity).

Thus, the solution is to just drop that 'else'.

Fixes #855.
2021-12-22 00:25:19 -08:00
..
src Fix regression with wall stuck flipping behavior exactly reversed 2021-12-22 00:25:19 -08:00
.dockerignore Run CI on CentOS 7 (#574) 2021-01-11 00:30:15 -05:00
.gitignore Don't recompile all files when the commit hash is changed 2020-12-25 20:17:01 -05:00
CMakeLists.txt Remove -sFORCE_FILESYSTEM=1 from compile options 2021-09-07 09:43:48 -07:00
CONTRIBUTORS.txt Update comments about contributor ordering 2021-08-24 09:42:23 -07:00
Dockerfile Update Dockerfile to SDL 2.0.16 2021-09-23 12:26:50 -07:00
fixupMac.sh Added my quick script to fixup Mac dylib paths 2021-09-01 12:07:57 -04:00
icon.ico Updated .ico 2021-09-03 15:57:16 -04:00
icon.rc Embedded .ico 2021-08-28 11:21:49 -04:00
README.md README.md: Link to #618 for old Ubuntu versions 2021-11-14 10:11:33 -08:00
version.cmake Untabify every single file 2021-09-06 18:56:39 -07:00

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 2.0.16+ 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). (If you're on Ubuntu and your Ubuntu is too old to have this SDL version, then see here for workarounds.)

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:\SDL2-2.0.16\include;C:\SDL2_mixer-2.0.4\include" -DSDL2_LIBRARIES="C:\SDL2-2.0.16\lib\x86\SDL2;C:\SDL2-2.0.16\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