JoltWrapper

Little C wrapper to make Jolt Physics C library compatible with Love 2D

Overview

Jolt Physics is a physics engine and JoltC a C version of the API which allows to be used in Love via the FFI library.

Because of LuaJit, callbacks cannot be triggered from other threads. Since Jolt does it, it creates panic errors. This little wrapper library has been made to workaround this problem.

How it works

The wrapper focus on handling OnContactAdded and OnContactRemoved callbacks by storing the arguments in arrays to be accessed later. The library use a mutex to lock and unlock the array (one per event) to prevent several threads from editing it at the same time. The mutex is handled via the Unix pthread library.

The library use a fixed array size to store the events. A counter has to be reset once the events have been consumed.

How to build

Refer to the file Wrapper/build.py.

How to use

Refer to the file Lua/demo.lua.

Notes

• The code provided (mainly the lua and python files) are not plug and play and more here as guidelines/context.
• The pthread library doesn't exist on Windows. Either compile with mingw on Windows (and include libwinpthread-1.dll), or use something like this Cross platform thread wrapper.
• This only handle the generic ContactListener, something similar for Character listener would need to be done as well.
• Jolt ensure that all callbacks are trigerred once the Update() call is done, hence why the event arrays are accessed after on Lua side.