comment on

I think that what you really want is the distance of a point to a segment, and not the distance to a line. Because a line is infinite, and the shortest distance of a point to a line might fall outside your segment.

In the case below, the distance of the point C to the line AB is CP. But P is outside of your segment, and what you really want is CA and not CP.

                 /
                x (B)
               /
              /
             /
 x (C)      x (A)
   `.      /
      `.  /
        `x
        / (P)
       /
      /
[download]

So, you must find the coordinate of P (the distance to the line) then check if P is outside of your segment. If it's outside, then you compute CA and CB and take the shortest.

In reply to Re: Algorithm: point with N distance of a line between two other points by choocroot
in thread Algorithm: point with N distance of a line between two other points by japhy

Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
Want more info? How to link or How to display code and escape characters are good places to start.


good chemistry is complicated, and a little bit messy -LW
	PerlMonks