Question by Pitomator · Nov 02, 2013 at 01:26 PM · collision collider box

Box Edge Collision Problems

Hi, I am making a game a little like brick breaker. You shoot a ball at boxes, then the box breaks and the ball should rebound. Instead of using a sphere collider for the ball I want to use a box collider, to insure that the ball always bounces of perfectly.

Now, when I shoot the ball at the box and the point of impact is the corner the ball bounces of in a random direction and looses velocity, although I am using no friction.

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I locked rotation, decreased time-steps, changed options in physics settings, tried to fix the problem with code and etc. Nothing seems to fix the problem. I am using a lot of OnCollision functions, it would be quite hard to use raycasting I believe. Because I would have to change loads of scripts. Is there a way around this? If I were to use Raycasting how would I do it? Thanks :)

problem.jpg (50.6 kB)

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pfjarschel · Mar 27, 2015 at 06:03 PM 0

Did you ever find a solution to this? I'm having a similar problem...

Pitomator · Mar 31, 2015 at 12:22 PM 1

I came up with a work around, at the end I wrote a piece of code that detects where the box collided (the contact point) and then I changed the velocity accordingly.

So, if I detected a collision on the top/bottom half, I inverted the vertical velocity of the object.

And if I detected a collision on the left/right side, I inverted the horizontal velocity.

I believe the new Unity 2D options solved this problem though. Good luck developing!

pfjarschel · Mar 31, 2015 at 12:32 PM 0

Yeah, that's the only solution I could think of, but my game is in 3D, so It's getting a little more complicated. The main problem is when the ball hits the point between two or more blocks...

Thanks for your answer, though! =)