Calculate angle of moving ball after collision with angled or sloped wall that is a 2D line segment

Posted by Ben Mc on Stack Overflow See other posts from Stack Overflow or by Ben Mc
Published on 2010-12-24T00:15:13Z Indexed on 2010/12/24 0:54 UTC
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android

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game-physics

If you have a "ball" inside a 2D polygon, made up of say, 4 line segments that act as bounding walls, how do you calculate the angle of the ball after the collision with the irregularly sloped wall?

I know how to make the ball bounce if the wall is horizontal, vertical, or at a 45 degree angle. I also have my code setup to detect a collision with the wall.

I've read about dot products and normals, but I cannot figure out how to implement these in Java / Android. I'm completely stumped and feel like I've looked up everything 10 pages deep in Google 10 times now. I'm burned out trying to figure this out, I hope someone can help.

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