pie.cpp

可以进行柱状图

// Pie.cpp: implementation of the CPie class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "Pie.h"
#include "math.h"
#include "gl/glut.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CPie::CPie()
{

}

CPie::~CPie()
{

}

void CPie::Draw()
{
	float angle; 
	glEnable(GL_SMOOTH);
	int i = 0;
	glBegin(GL_TRIANGLE_FAN);

		glColor3f(0.5,0.5,0.0);
		glVertex2f(0.0f,0.0f - 50);

		for(angle = 0.0;angle<=2 * 3.14;angle += 0.01)
		{
			if(i - angle + 0.001 <= 0.009 && i - angle + 0.001 >= 0 && angle != 6.28)
			{
				if(i %2 == 0)
					glColor3f(0.0,1.0,0.0);
				else
					glColor3f(1.0,0.0,0.0);
				i++;
			}
			glVertex2f(70 * cosf(angle),70 * sinf(angle) - 50);
		}
		glVertex2f(70 * cosf(angle),0.01 - 50);

	glEnd();
	glFlush();

}