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//==================================================================
// Copyright 2002, softSurfer (www.softsurfer.com)
// This code may be freely used and modified for any purpose
// providing that this copyright notice is included with it.
// SoftSurfer makes no warranty for this code, and cannot be held
// liable for any real or imagined damage resulting from it's use.
// Users of this code must verify correctness for their application.
//==================================================================
// Heavily modified by Randal A. Koene, 20050111
#ifndef SS_Point2D_H
#define SS_Point2D_H
#include <iostream>
using namespace std;
#ifndef SS_Vector2D_H
class Vector2D;
#endif
// utility macros
#define Pabs(x) ((x) >= 0 ? x : -(x))
#define Pmin(x,y) ((x) < (y) ? (x) : (y))
#define Pmax(x,y) ((x) > (y) ? (x) : (y))
#define PDIMSIZE 2
class Point2D {
friend class Vector2D;
protected:
double x, y; // y=0 for 1D
public:
Point2D(): x(0.0), y(0.0) {}
Point2D(double X, double Y): x(X), y(Y) {}
~Point2D() {};
double X() const { return x; }
double Y() const { return y; }
void set_X(double X) { x = X; }
void set_Y(double Y) { y = Y; }
void add_X(double X) { x += X; }
void add_Y(double Y) { y += Y; }
double & operator [] (unsigned int n) {
if (n==0) return x;
else return y;
}
friend istream& operator>>( istream & input, Point2D & P);
friend ostream& operator<<( ostream & output, Point2D P);
int operator==( Point2D Q) { return (x==Q.x && y==Q.y); }
int operator!=( Point2D Q) { return (x!=Q.x || y!=Q.y); }
Vector2D operator-( Point2D); // Vector2D difference
Point2D operator+( Vector2D); // +translate
Point2D operator-( Vector2D); // -translate
Point2D& operator+=( Vector2D); // inc translate
Point2D& operator-=( Vector2D); // dec translate
//----------------------------------------------------------
// Point2D Scalar Operations (convenient but often illegal)
// using any type of scalar (int, float, or double)
// are not valid for points in general,
// unless they are 'affine' as coeffs of
// a sum in which all the coeffs add to 1,
// such as: the sum (a*P + b*Q) with (a+b == 1).
// The programmer must enforce this (if they want to).
// Scalar Multiplication
friend Point2D operator*( int, Point2D);
friend Point2D operator*( double, Point2D);
friend Point2D operator*( Point2D, int);
friend Point2D operator*( Point2D, double);
// Scalar Division
friend Point2D operator/( Point2D, int);
friend Point2D operator/( Point2D, double);
//----------------------------------------------------------
// Point2D Addition (also convenient but often illegal)
// is not valid unless part of an affine sum.
// The programmer must enforce this (if they want to).
friend Point2D operator+( Point2D, Point2D); // add points
// Affine Sum
// Returns weighted sum, even when not affine, but...
// Tests if coeffs add to 1. If not, sets: err = Esum.
friend Point2D asum( int, int[], Point2D[], int * err = 0);
friend Point2D asum( int, double[], Point2D[], int * err = 0);
//----------------------------------------------------------
// Point2D Relations
friend double distance( Point2D, Point2D); // Distance
friend double distance2( Point2D, Point2D); // Distance^2
double distance(Point2D & P); // Distance
double isLeft( Point2D, Point2D, int * err = 0); // 2D only
double Area( Point2D, Point2D); // any dim for triangle PPP
// Collinearity Conditions (any dim n)
bool isOnLine( Point2D, Point2D, char); // is On line (char= flag)
bool isOnLine( Point2D, Point2D); // is On line (flag= all)
bool isBefore( Point2D, Point2D); // is On line (flag= before)
bool isBetween( Point2D, Point2D); // is On line (flag= between)
bool isAfter( Point2D, Point2D); // is On line (flag= after)
bool isOnRay( Point2D, Point2D); // is On line (flag= between|after)
bool isZero() { return ((x==0.0) && (y==0.0)); }
};
#endif
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