ofxBox2d

Introduction

This is a simple wrapper for box2d using Openframeworks. The examples below are still in progressive, but should be stable for the most part. Please open up a issue if you have suggestions or find bugs. The wrapper is using the version Box2D v2.3

Thanks, Todd

Instructions

When making a vector of objects you need to be careful. You either need to make a vector of pointers of use the shared_ptr object.

Everytime you push into the vector circles the object is destroyed and the created. This causing issues for the b2dBody body object owned by box2d.

Incorrect way to store objects.

vector <ofxBox2dCircle> circles;
ofxBox2dCircle circle;
circles.push_back(circle);

Here is the how to create a vector of box2d objects.

// in your header files
vector <shared_ptr<ofxBox2dCircle> > circles;


// now add a circle to the vector
shared_ptr<ofxBox2dCircle> circle = shared_ptr<ofxBox2dCircle>(new ofxBox2dCircle);

// to grab the pointer you use the get() function of shared_ptr (std::shared_ptr)
circle.get()->setPhysics(3.0, 0.53, 0.1);
circle.get()->setup(box2d.getWorld(), 100, 100, 10);
circles.push_back(circle);

Installation

Place ofxBox2d within a folder in the apps folder of the OF dir tree:

openframeworks/addons/ofxBox2d

Compatibility

The master branch is compatible with the current release of openFrameworks, and the develop branch tries to stay up to date with openFrameworks on GitHub.