[Read-only] Collision category, specified using powers of 2, with 32 different collision categories available.
Zh
[只读] 碰撞类别，使用2的幂次方值指定，有32种不同的碰撞类别可用。
group
group:number = 0
En
[Read-only] Specifies the collision group to which the body belongs, default is 0, the collision rules are as follows:
If the group values of two objects are equal:
If the group value is greater than zero, they will always collide.
If the group value is less than zero, they will never collide.
If the group value is equal to 0, then rule 3 is used.
If the group values are not equal, then rule 3 is used.
Each rigidbody has a category, this property receives a bit field, the range is the power of 2 in the range of [1,2^31].
Each rigidbody also has a mask category, which specifies the sum of the category values it collides with (the value is the result of bitwise AND of all categories).
[Read-only] Specifies the category of collision bit mask, the result of category bitwise operation.
Each rigidbody also has a mask category, which specifies the sum of the category values it collides with (the value is the result of bitwise AND of all categories).
Zh
[只读] 指定冲突位掩码碰撞的类别，category 位操作的结果。
每个刚体也都有一个 mask 类别，指定与其碰撞的类别值之和（值是所有 category 按位 AND 的值）。
访问器
density
getdensity():number
返回 number
En
The density value. The value can be zero or a positive number. It is recommended to use similar densities to improve stacking stability. The default value is 10.
Zh
密度值。值可以为零或者是正数，建议使用相似的密度以改善堆叠稳定性。默认值为 10。
setdensity(value:number):void
参数
value: number
返回 void
friction
getfriction():number
返回 number
En
The friction coefficient. The value ranges from 0 to 1, the larger the value, the greater the friction. The default value is 0.2.
Zh
摩擦力。取值范围0-1，值越大，摩擦越大。默认值为0.2。
setfriction(value:number):void
参数
value: number
返回 void
restitution
getrestitution():number
返回 number
En
The restitution coefficient. The value ranges from 0 to 1, the larger the value, the greater the elasticity. The default value is 0.
En
[Read-only] Collision category, specified using powers of 2, with 32 different collision categories available.
Zh
[只读] 碰撞类别，使用2的幂次方值指定，有32种不同的碰撞类别可用。