Package edu.cnu.mdi.util

Class MathUtils

java.lang.Object

edu.cnu.mdi.util.MathUtils

public final class MathUtils
extends Object

General mathematical helpers used by drawable geometry.

Method Summary

Modifier and Type	Method	Description
static double	perpendicularIntersection(double x1, double y1, double x2, double y2, Point2D.Double wp, Point2D.Double pintersect)	Given two points p0 and p1, imagine a line from p0 to p1.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

perpendicularIntersection

public static double perpendicularIntersection(double x1,
 double y1,
 double x2,
 double y2,
 Point2D.Double wp,
 Point2D.Double pintersect)

Given two points p0 and p1, imagine a line from p0 to p1. Take the line to be parameterized by parameter t so that at t = 0 we are at p0 and t = 1 we are at p1.

Parameters:

x1 - x coordinate of one endpoint

y1 - y coordinate of one endpoint

x2 - x coordinate of other endpoint

y2 - y coordinate of other endpoint

wp - the point from which we drop a perpendicular to p0 -> p1

pintersect - the intersection point of the perpendicular and the line containing p0-p1. It may or may not actually be between p0 and p1, as specified by the return argument.

Returns:

the value of the t parameter. If it is between 0 and 1 the intersection is on the line. If t less than 0 the intersection is on the "infinite line" but not on p0->p1, it is on the p0 side. If t > 1 the intersection is on the p1 side.