Phaser API Documentation

Description:

An Object that specifies the collision filtering properties of this body.

Collisions between two bodies will obey the following rules:

• If the two bodies have the same non-zero value of collisionFilter.group, they will always collide if the value is positive, and they will never collide if the value is negative.
• If the two bodies have different values of collisionFilter.group or if one (or both) of the bodies has a value of 0, then the category/mask rules apply as follows:

Each body belongs to a collision category, given by collisionFilter.category. This value is used as a bit field and the category should have only one bit set, meaning that the value of this property is a power of two in the range [1, 2^31]. Thus, there are 32 different collision categories available.

Each body also defines a collision bitmask, given by collisionFilter.mask which specifies the categories it collides with (the value is the bitwise AND value of all these categories).

Using the category/mask rules, two bodies A and B collide if each includes the other's category in its mask, i.e. (categoryA & maskB) !== 0 and (categoryB & maskA) !== 0 are both true.