LiquidFun Rust

Rust bindings for LiquidFun.

Model LiquidFun C++ API as closely as possible.
Documentation for C++ API should be usable for Rust API.
Document places where Rust API varries from C++ API.

Usage

First, add the following to your Cargo.toml:

[dependencies]

liquidfun = "*"

Next, add this to your crate root:

extern crate liquidfun;

Example

extern crate liquidfun;

use liquidfun::box2d::common::math::*;
use liquidfun::box2d::dynamics::world::*;

#[test]
fn hello_world() {

	// Define the gravity vector.
	let gravity = Vec2::new(0.0, -10.0);

	// Construct a world object, which will hold and simulate the rigid bodies.
	let mut world = World::new(&gravity);
	assert_eq!(gravity, world.get_gravity());

}

Status

The LiquidFun Hello World example compiles and runs. More bindings will be added as needed by projects that depend on LiquidFun Rust.

Passing structs by value from C++ to Rust

make a new typedef struct with same name as C++ struct but with c_ prefix
add just the data parts from the C++ struct, make sure both struct members have the same order

// C++
struct b2Vec2 {
	b2Vec2() {}
	...
	float32 x, y;
};

// new C struct
typedef struct c_b2Vec2 { float32 x, y; } c_b2Vec2;

make a casting function
cast C++ struct to new C struct and pass back to rust

c_b2Vec2* cast(b2Vec2* v) {
    return reinterpret_cast<c_b2Vec2*>(v);
}

c_b2Vec2 sendStructFromCppToRustByValue() {
	b2Vec2 tmp;
    return *cast(&tmp);
}

Thank You

Erin Catto for Box2D

Google for LiquidFun