Is there any possibility to....

[Jack]

Is there any possibility to:

1) Prohibit body to move across one of the main axises (X, Y, or Z)?
2) Prohibit body to have angular velocity?

[Erwin Coumans]

Is there any possibility to:

1) Prohibit body to move across one of the main axises (X, Y, or Z)?

Yes, you can use the btGeneric6DofConstraint to do this. Just lock 1 axis, and leave 2 linear axis free.

2) Prohibit body to have angular velocity?

This can be done with the btGeneric6DofConstraint too, just lock the 3 angular axis.

Another solution is to prevent impulses to add angular velocity. This can be handy for a basic character controller.
Use btRigidBody's setAngularFactor and set it to zero.

Hope this helps,
Erwin

[Jack]

btGeneric6DofConstraint requires second body. But what if I have no second body? Second body is World....

[Erwin Coumans]

btGeneric6DofConstraint requires second body. But what if I have no second body? Second body is World....

You can provide a static rigidbody, with mass 0, and no collision shape. I'm pretty busy otherwise I would give you some samplecode, but there must be some sample/snippet that does this.

Hope this helps,
Erwin