Physics.Ninja#Ninja

Ninja Physics. The Ninja Physics system was created in Flash by Metanet Software and ported to JavaScript by Richard Davey.

It allows for AABB and Circle to Tile collision. Tiles can be any of 34 different types, including slopes, convex and concave shapes.

It does what it does very well, but is ripe for expansion and optimisation. Here are some features that I'd love to see the community add:

• AABB to AABB collision
• AABB to Circle collision
• AABB and Circle 'immovable' property support
• n-way collision, so an AABB/Circle could pass through a tile from below and land upon it.
• QuadTree or spatial grid for faster Body vs. Tile Group look-ups.
• Optimise the internal vector math and reduce the quantity of temporary vars created.
• Expand Gravity and Bounce to allow for separate x/y axis values.
• Support Bodies linked to Sprites that don't have anchor set to 0.5

Feel free to attempt any of the above and submit a Pull Request with your code! Be sure to include test cases proving they work.