First supporter! Thank you!

In celebration:

Add ACEs:

• Set collision filter group
• Set collision filter group mask

Details:

• Filter groups are power of 2: 0,1,2,4,8,16,32, etc.
• Filter group mask are an OR of the all the filter groups to include (can also just add all the groups, same effect as OR in this case)
• How to filter collisions using Body.collisionFilterGroup and Body.collisionFilterMask.
• The filters are applied inside the broadphase. It can be used to allow or disallow collisions between bodies.
• To disable mask / filter use a value of -1
• A collision is allowed if:

  
  

  • (bodyA.collisionFilterGroup & bodyB.collisionFilterMask) && (bodyB.collisionFilterGroup & bodyA.collisionFilterMask)
• These are indeed bitwise operations. Learn more about that here: http://en.wikipedia.org/wiki/Bitwise_operation