PHP - [c++] Trying To Zoom And Pan An Object

#include "OGLPieChart.h"
#include <Windows.h>
#include <gl/GL.h>
#include <math.h>
#include <fstream>
#include <sstream>
#include <iostream>

using namespace std;

OGLPieChart::OGLPieChart()
{
	//init the OGLRectangle to a fixed size
	m_topleft.SetX(-50.0f);
	m_topleft.SetY(50.0f);

	m_bottomright.SetX(50.0f);
	m_bottomright.SetY(-50.0f);
}

OGLPieChart::~OGLPieChart()
{
	
}

void OGLPieChart::Render()
{
	float PI = 3.14159;
	float radius = 200;
	string DataLine;

	//Changed from int(s) to float(s) to stop angle equation equalling 0 later on.
	float NeverMarried = 0;
	float MarriedCivSpouse = 0;
	float Widowed = 0;
	float Divorced = 0;
	float Seperated = 0;
	float MarriedSpouseAbsent = 0;

	//Only reading from file so using ifstream instead of ofstream and fstream
	ifstream DataFile("..\\.\\adult_test_data.csv");

	if (!DataFile.is_open())
	{
		cout << "Unable to open file.";
		return;
	}
	else
	{
		string DataLine;

		while (!DataFile.eof())
		{
			getline(DataFile, DataLine);
			istringstream StringData(DataLine);

			while (StringData)
			{
				getline(StringData, DataLine, ',');

				if (DataLine == " Never-married")
				{
					NeverMarried += 1;
				}
				else if (DataLine == " Married-civ-spouse")
				{
					MarriedCivSpouse += 1;
				}
				else if (DataLine == " Widowed")
				{
					Widowed += 1;
				}
				else if (DataLine == " Divorced")
				{
					Divorced += 1;
				}
				else if (DataLine == " Separated")
				{
					Seperated += 1;
				}
				else if (DataLine == " Married-spouse-absent")
				{
					MarriedSpouseAbsent += 1;
				}
			}
		}
	}

	DataFile.close();

	int MaritalStatusTotal = (NeverMarried + MarriedCivSpouse + Widowed + Divorced + Seperated + MarriedSpouseAbsent);

	float NeverMarriedAngle = (NeverMarried / MaritalStatusTotal) * 360;
	float MarriedCivSpouseAngle = (MarriedCivSpouse / MaritalStatusTotal) * 360;
	float WidowedAngle = (Widowed / MaritalStatusTotal) * 360;
	float DivorcedAngle = (Divorced / MaritalStatusTotal) * 360;
	float SeperatedAngle = (Seperated / MaritalStatusTotal) * 360;
	float MarriedSpouseAbsentAngle = (MarriedSpouseAbsent / MaritalStatusTotal) * 360;

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(0.0f, 1.0f, 1.0f);
	glVertex2f(0, 0);

	for (int i = 0; i <= NeverMarriedAngle; i++)
	{
		glVertex2f(radius * cos(i * PI /  180), radius * sin(i * PI / 180));
	}

	glEnd();

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(1.0f, 1.0f, 0.0f);
	glVertex2f(0, 0);

	for (int j = NeverMarriedAngle; j <= NeverMarriedAngle + MarriedCivSpouseAngle; j++)
	{
		glVertex2f(radius * cos(j * PI / 180), radius * sin(j * PI / 180));
	}

	glEnd();

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(0.2, 0.3, 0.8);
	glVertex2f(0, 0);

	for (int k = NeverMarriedAngle + MarriedCivSpouseAngle; k <= NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle; k++)
	{
		glVertex2f(radius * cos(k * PI / 180), radius * sin(k * PI / 180));
	}

	glEnd();

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(0.1, 0.1, 1);
	glVertex2f(0, 0);

	for (int a = NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle; a <= NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle + DivorcedAngle; a++)
	{
		glVertex2f(radius * cos(a * PI / 180), radius * sin(a * PI / 180));
	}

	glEnd();

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(0.1, 0.2, 0.4);
	glVertex2f(0, 0);

	for (int b = NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle + DivorcedAngle; b <= NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle + DivorcedAngle + SeperatedAngle; b++)
	{
		glVertex2f(radius * cos(b * PI / 180), radius * sin(b * PI / 180));
	}

	glEnd();

	glBegin(GL_TRIANGLE_FAN);
	glColor3f(0.8, 0.3, 0.1);
	glVertex2f(0, 0);

	for (int c = NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle + DivorcedAngle + SeperatedAngle; c <= NeverMarriedAngle + MarriedCivSpouseAngle + WidowedAngle + DivorcedAngle + SeperatedAngle + MarriedSpouseAbsentAngle; c++)
	{
		glVertex2f(radius * cos(c * PI / 180), radius * sin(c * PI / 180));
	}

	glEnd();
}

bool OGLPieChart::MouseMove( int x, int y )
{
	m_topleft.SetX( (float) x );
	m_topleft.SetY( (float) y );
	
	m_bottomright.SetX( (float) x + 100.0f );
	m_bottomright.SetY( (float) y + 100.0f);
	

	return true;
}

bool OGLPieChart::MouseLBUp( int x, int y )
{
	return true;
}
bool OGLPieChart::MouseLBDown( int x, int y )
{
	return true;
}