Today while implementing **Breps in **my dataStructure i got a interesting problem to solve .

Basically needed to figure out the distance of a **Line -Segment** from a specified point so that i can see which is the closet edge in a Object.

Its a Line Segemnt and not whole Line from which we need to find distance . So perpendicular distance is not the smallest distance if the perpendicular does not fall on that segment .So how to solve this.

Well the solution i was able to came up is :

1 ) Make a Plane from two points of LineSegment and specified Pt given .

2) On this plane make two Lines Passing through the end Points of the Segemnt and Perpendicular to it.

3) Now say D is the distance between two end Points of the Segment.

And D1 =Distance of Specified Pt from first Perpendicular.

D2=Distance of Specified Pt from second Perpendicular.

4) If D is greater than D1 and D2 . Than minimum distance of that Specified pt will be Perpendicluar from this point on

the Line Equation.

5 ) Otherwise shorter of the distance between Specified pt and two pts of the Segment is the minimum distance.

Not Bad huh!