If I have a game object that is a rigidbody, and I have a script to control the rigidbody , everything is fine. However if I add a collider to that gameobject, then everything goes crazy. Literally the control that worked before in the script no longer works as before. Unpredictable movement results. Disable the collider and back to normal.
I’ve tried this a few different times, different scripts, etc so I don’t think it is code related exactly, but perhaps a just the way Unity works. Is that true? Not a Unity bug?
Yes I know I can use a character controller or directly move or manipulate transforms. But in some cases using AddForce or AddForceAtPoint is the best way to simulate something (like an airplane). I also know I can use Raycasting as an alternative to detecting collisions. But is there anyway to get colliders to work while also using AddForce in scripts?
It’s actually the other way round. A Rigidbody without a collider does act strange because a Rigidbody always needs a collider to work correctly. Unity will determine some values from the attached collider(s) as you figured out:
Adding a collider doesn’t change rigidbody behavior, aside of course from enabling collisions or triggers. There’s no bug; it’s definitely something in your code or your setup. Also you can’t use raycasting to detect collisions without colliders–you need something for the rays to hit, and it’s not really an alternative in many cases anyway. Without knowing anything about what you’re doing, my only suggestion is that if you’re using parents/children, make sure that the children do not have rigidbodies. In this case, having children with colliders makes a single compound collider, so only the parent should have a rigidbody.