*sigh* Collisions on Instantiated GameObjects...

Unity Engine
1

You know, projectiles, bullets, metal thing that comes out from big boom sticks and makes things bleed.

Well, they wont. I have no idea whats going wrong here, as far as im aware, everything is dead simple.

Ive got the scripts in place to click and create a bullet that travels through the air. When i dont have the
Physics.IgnoreCollision(objCreatedBullet.collider, collider); the bullets pretty much disappear while for a moment giving me trouble moving (no doubt because its detecting my collision script and removing itself automatically as per it should)

The problem boils down to this:

void OnCollisionEnter(Collision Other)
	{
		Debug.Log("Hit: " + Other.gameObject.name);
		removeMe(); // remove the bullet if it hit anything else
		
	}

Or at least, so i would think.

When launching a bullet at a cube created within Unity, the bullet goes straight through and no Debug information is received in the log. No matter what i do with the collision box of that cube.
So i created a simple Mesh in Maya, no dice, not even when i gave it a capsule barrier for fun.

All bullets go straight through everything, except the player when that Physics.Ignore code is in place.

I have no idea if any of this makes any sense to whats going on, so heres a screenshot

275732--9905--$screen_shot_2010_03_12_at_95412_am_145.jpg
275732--9905--$screen_shot_2010_03_12_at_95412_am_145.jpg1672×994 408 KB

2

Your bullet may be moving too fast (as bullets tend to do…). If you want to test that, reduce the velocity of the bullet to a relatively low velocity and see if you get the same behavior. If that is the case, there is a script in the wiki for fast collisions (I think it is called “donGoThruThings”).

Anyway, what happens is the object travels so far per frame, it may have already passed through the target before it does the next check for collision. The solution is to either slow down the bullet, or have it check, each update, if it passed through a collider and reset its position accordingly (what the script basically does).

3

actually the bullets are moving quite slow, and ive even expanded the cubes hit area to be really fat just to check for that (I’ve worked in Flash for countless years, that whole speed thing is definitely not a new trap card to me :))

4

How are you moving the bullets? You will generally not get correct collisions if you change the bullets’ positions with transform.Translate or by setting transform.position. You should use rigidbody.AddForce and friends to push the objects with forces.