ABOUT: this is really a clone of the chipmunk engine. i am testing my own stuff with it... i left the original readme below. it now compiles on ubuntu. i removed a bunch of the ._ files

ABOUT: Chipmunk is a simple, lightweight and fast 2D rigid body physics library written in C. It's licensed under the unrestrictive, OSI approved MIT license. My aim is to give 2D developers access the same quality of physics you find in newer 3D games. I hope you enjoy using Chipmunk, and please consider donating to help make it worth our time to continue to support Chipmunk with great new features.

CONTRACTING: Howling Moon Software (my company) is available for contracting if you want to make the physics in your game really stand out. Given our unique experience with the library, we can help you use Chipmunk to it's fullest potential. Feel free to contact us through our webpage: http://howlingmoonsoftware.com/contracting.php

Objective-Chipmunk: The Objective-Chipmunk directory contains an Objective-C wrapper for the Chipmunk Physics Library as well as some sample code from shipping iPhone Apps. Chipmunk was written in C to allow it to The primary advantages of a native Objective-C API include integrating with the Cocoa memory management model and the Chipmunk Object protocol. The Chipmunk Object protocol unifies the basic Chipmunk types as well as making it easy to create custom composite collections of the basic types. Additionally, the wrapper adds many convenience methods for doing common setup tasks as well as helper methods that integrate it with the rest of the Cocoa Touch API. The wrapper tries to do things the Objective-C way, adding useful method variations where it makes sense to do so.

BUILDING: Mac OS X: There is an included XCode project file for building the static library and demo application. Alteratively you could use the CMake files.

iPhone: If you want a native Objective-C API, check out the Objective-Chipmunk directory for the Objective-C binding and some sample code from shipping iPhone Apps. Otherwise, the XCode project can build a static library with all the proper compiler settings. Additionally, if you run the iphonestatic.sh script in the macosx/ directory, it will build you a fat library compiled as release for the device and debug for the simulator. After building that, just copy the static lib and include/chipmunk/ directory to your project.

UNIX: A forum user was kind enough to make a set of CMake files for Chipmunk. This will require you to have CMake installed. To build run 'cmake .' then 'make'. This should build a dynamic library, a static library, and the demo application.

Windows: There is an included MSVC project for building the library and demo application. I do not personally maintain the MSVC project. It needs someone to update it for the new include structure.

Ruby: I've been using maintaining a Ruby extension for Chipmunk, but at this time is not up to date with all the latest changes. A forum member has been working on an FFI based extention, and that may be a better way to take advantage of Chipmunk from Ruby. Another forum user has offered to maintain the non-FFI version of the extension. Stay tuned.

GETTING STARTED: First of all, you can find the C API documentation here: http://code.google.com/p/chipmunk-physics/wiki/Documentation

A good starting point is to take a look at the included Demo application. The demos all just set up a Chipmunk simulation space and the demo app draws the graphics directly out of that. This makes it easy to see how the Chipmunk API works without worrying about the graphics code. You are free to use the demo drawing routines in your own projects, though it is certainly not the recommended way of drawing Chipmunk objects as it pokes around at the undocumented parts of Chipmunk.

FORUM: http://www.slembcke.net/forums

CONTACT: [email protected] (also on Google Talk)

CHANGES SINCE 5.1.0:

• OPTIMIZATION: Chipmunk structs used within the solver are now allocated linearly in large blocks. This is much more CPU cache friendly. Programs have seen up to 50% performance improvements though 15-20% should be expected.
• API: Shape references in cpArbiter structs changed to private_a and private_b to discourage accessing the fields directly and getting them out of order. You should be using cpArbiterGetShapes() or CP_ARBITER_GET_SHAPES() to access the shapes in the correct order.
• API: Added assertion error messages as well as warnings and covered many new assertion cases.
• FIX: separate() callbacks are called before shapes are removed from the space to prevent dangling pointers.
• NEW: Added convenience functions for creating box shapes and calculating moments.

CHANGES SINCE 5.0.0:

• FIX: fixed a NaN issue that was causing raycasts for horizontal or vertical lines to end up in an infinite loop
• FIX: fixed a number of memory leaks
• FIX: fixed warnings for various compiler/OS combinations
• API: Rejecting a collision from a begin() callback permanently rejects the collision until separation
• API: Erroneous collision type parameterns removed from cpSpaceDefaulteCollisionHandler()
• MOVE: FFI declarations of inlined functions into their own header
• MOVE: Rearranged the project structure to separate out the header files into a separate include/ directory.
• NEW: Added a static library target for the iPhone.
• NEW: Type changes when building on the iPhone to make it friendlier to other iPhone APIs
• NEW: Added an AABB query to complement point and segment queries
• NEW: CP_NO_GROUP and CP_ALL_LAYERS constants

CHANGES SINCE 4.x:

• Brand new Joint/Constraint API: New constraints can be added easily and are much more flexible than the old joint system
• Efficient Segment Queries - Like raycasting, but with line segments.
• Brand new collision callback API: Collision begin/separate events, API for removal of objects within callbacks, more programable control over collision handling.