Passing Class Objects, Instances

--------------------------------------------------------------------------------

I have a project creating a cartesian point, then a line segment, then a line comparison. Each has its own class .h and .cpp file. Main just starts the program to CartesianPoint test, in the point class. My question is after I create an instance of the point class and create a point, say P1, how can I then pass this object, (an instance of the point class) to the LineSegment class, to find slope and such. Line inherits LineSegment which inherits CartesianPoint. I have no idea what I'm doing.

Thanks


Heer's the code so far. I need help passing a CartesianPoint object to LineSegment, and I need help learning how to manipulate it. I believe this is called aggregation and/or composition, I have spent three days now just to find the terms of what I need to learn how to do. Instead of learning how to do it.
------------------------------------------------------

include <iostream>

#include "CartesianPoint.h"
#include "LineSegment.h"
#include "Line.h"

#include "stdafx.h"


using namespace std;




double main()
{


CartesianPoint::test();

LineSegment::test();


return (0);

} // end main

-----------------------------------------
#ifndef CARTESIANPOINT_H
#define CARTESIANPOINT_H


#include "stdafx.h"



class CartesianPoint {

public:


CartesianPoint();

CartesianPoint(double xx, double yy);

double getx();

double gety();

void set(double xx, double yy);

static void test();

void print();

//void print(double pOne, double pTwo, double pThree, double pFour);

virtual ~CartesianPoint();



protected:

double x;
double y;



}; // end clas CartesianPoint

#endif


--------------------------------------------
#include <iostream>
#include <iomanip>
#include <cmath>
#include "stdafx.h"

#include "CartesianPoint.h"
#include "LineSegment.h"
#include "Line.h"

using namespace std;





CartesianPoint::CartesianPoint()
{
x = 0;
y = 0;

}


CartesianPoint::CartesianPoint(double xx, double yy)
{
x = xx;
y = yy;

}


CartesianPoint p1;
CartesianPoint p2;
CartesianPoint p3;
CartesianPoint p4;



void CartesianPoint::test(){


p1.set(1.2,2.2);

p2.set(8.2,68.2);

p3.set(9.8,50.2);

p4.set(11.2,6.2);


p1.print();
p2.print();
p3.print();
p4.print();
p1.print();

}



void CartesianPoint::set(double xx,double yy)
{

x = xx;
y = yy;

}


double CartesianPoint::getx()
{
double temp;
temp = x;
return temp;
}



double CartesianPoint::gety()
{
double temp;
temp = y;
return temp;
}


void CartesianPoint::print()
{

cout<<"The point is: ("<<getx()<<", "<<gety()<<")"<<endl<<endl;

}



CartesianPoint::~CartesianPoint()
{

}


--------------------------------------------

#ifndef LINESEGMENT_H
#define LINESEGMENT_H

#include "CartesianPoint.h"
#include "Line.h"

class CartesianPoint;
//class Line;

class LineSegment : public CartesianPoint {

public:

LineSegment(); // default constructor

LineSegment(CartesianPoint V1, CartesianPoint V2);

LineSegment(CartesianPoint V1, CartesianPoint V2,
CartesianPoint V3, CartesianPoint V4);




double getMidPoint();

CartesianPoint midPoint();





double getPerpendicularBisector();

double perpendicularBisector();



double getSlope();

void printLine();

static void test();

virtual ~LineSegment();



protected:

double m;
double b;


CartesianPoint p1;
CartesianPoint p2;
CartesianPoint p3;
CartesianPoint p4;



// double m1;
// double m2;

// double slopeLine1;
// double slopeLine2;

// Cartesian X1;
// Cartesian X2;
// Cartesian Y1;
// Cartesian Y2;



}; // end clas LineSegment

#endif

---------------------------------------------------


#include <iostream>
#include <iomanip>
#include <cmath>
#include "stdafx.h"

#include "CartesianPoint.h"
#include "LineSegment.h"

using namespace std;



LineSegment::LineSegment()
{
m = 0;
b = 0;

}



LineSegment::LineSegment(CartesianPoint V1, CartesianPoint V2)
{

p1 = V1;
p2 = V2;

m = 0;
b = 0;

}



LineSegment::LineSegment(CartesianPoint V1, CartesianPoint V2,
CartesianPoint V3, CartesianPoint V4)
{
p1 = V1;
p2 = V2;
p3 = V3;
p4 = V4;

m = 0;
b = 0;

}
CartesianPoint p1;

// LineSegment L1(CartesianPoint(1,1), CartesianPoint(1,1);





void LineSegment::test()
{




}


double LineSegment::getSlope()
{
double temp;




temp = m;

return temp;
}





void LineSegment::printLine()
{


}





LineSegment::~LineSegment()
{

}






-----------------------------------------------------