Are you sure dx, dy aren't so big that the ball teleports right past the line? It may be that all the ball needs to do is quantum tunnel far enough that the center of the ball is on the other side of the line? Maybe you could post a little code showing your calculation and indicate the range dx, dy are likely to take?

Perl reduces RSI - it saves typing

In reply to Re: Some simple 2d game-related maths questions by GrandFather
in thread Some simple 2d game-related maths questions by skx

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