Box to wall collision in C

Question

anonymous · Answer

I have a program I need to write in C that has a ball start at a randomly seeded origin point within a 2D box. From there, it uses a command line argument to decide the angle the ball is projected at. From there, we need to find the angle it bounces off, and how far away from the origin it was. Any ideas?

e.mccormick · Answer

When you look at a bounce off a flat surface, the direction is based on the angle.  How you are going to do it is all goin to depend on how you are getting the slope or angle.

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e.mccormick · Answer

That leads to this:
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e.mccormick · Answer

By slope, note the difference is just the sign change on y.
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By angle, you can find angles that match and do some math.  and A+B=180 degrees, so you can do some angle math.
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