math - Function for finding the distance between a point and an edge in java -

does have function in java finding shortest distance between point , line segment/edge? every example find in language , uses bunch of sub functions. can't based on assumption perpendicular.

update

i ported on python function java. if @ math , can verify appreciate it. x , y point, , other params line segment.

public float pdistance(float x, float y, float x1, float y1, float x2, float y2) {            float = x - x1;           float b = y - y1;           float c = x2 - x1;           float d = y2 - y1;            float dot = * c + b * d;           float len_sq = c * c + d * d;           float param = -1;           if (len_sq != 0) //in case of 0 length line               param = dot / len_sq;            float xx, yy;            if (param < 0) {             xx = x1;             yy = y1;           }           else if (param > 1) {             xx = x2;             yy = y2;           }           else {             xx = x1 + param * c;             yy = y1 + param * d;           }            float dx = x - xx;           float dy = y - yy;           return (float) math.sqrt(dx * dx + dy * dy);         } 

we can simplify things bit. don't need calculate param. can find vector v @ right angles line. take dot product of vector (a,b). in 2d easy enough find vector orthogonal (c,d), (-d,c).

public float pdistance(float x, float y, float x1, float y1, float x2, float y2) {        float = x - x1; // position of point rel 1 end of line       float b = y - y1;       float c = x2 - x1; // vector along line       float d = y2 - y1;       float e = -d; // orthogonal vector       float f = c;        float dot = * e + b * f;       float len_sq = e * e + f * f;        return (float) math.abs(dot) / math.sqrt(len_sq);     } 

if worried performance can easier work squared distances last line be

      return (float) dot * dot / len_sq; 

this saves having calculate square root. if want calculate closest edge, find squared distances each edge , select smallest.

this function find distance infinite line rather line segment. may not want. solution in question differs in happens if point beyond 2 ends of line segment. there find distance closest end point.