Point on Line-Segment Distance Away from a Point?

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I am looking for an algorithm (or the name of the algorithm) that will find a point on a line-segment, if such a point exists, that is some given distance away from another point that not on the line-segment. I.e. , There exist, three points A, B, C; and possibly a fourth D.

Where AB makes up a line-segment, and point C is another point somewhere OFF of the line-segment AB. Find a point D, if such point exists, that appears on the line-segment AB that is a given distance distance away from point C. Algorithm math computational-geometry link|improve this question asked Nov 20 '10 at 17:11Ryan453314 75% accept rate.

Look here: Circle-Line Intersection C is the circles middle and distance is the radius. Note that there may be two resulting points and that you have to check whether the point is actually on your line (or on the line that you would get by extending it).

This is a good boolean test, to check if there is such a point D. However, it does not look like it will tell me what the point(s) D is/are. Also, it looks like this is for an infinite line, I need a line-segment.

Thanks, though for the suggestion. – Ryan Nov 21 '10 at 16:20.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.