这个程序哪里出问题了。。我调试不出来啊。。大神帮帮忙啊

#include "windows.h"
#include "glut.h"
#include "math.h"
#define width 640
#define height 480
void drawArc(double x,double y,double start_angle,double end_angle,double delta_angle,double radius,bool fill)
{
if (fill)
{
glBegin(GL_TRIANGLE_FAN);
}
else
{
glBegin(GL_LINE_STRIP);
}
for (double i=start_angle;i<=end_angle;i+=delta_angle)
{
double vx=x+radius * cos(i);
double vy=y+radius*sin(i);
glVertex2d(vx,vy);
}
glEnd();
}
void drawCircle(double x, double y, double radius,bool fill)
{
double pi=acos(-1.0);
drawArc(x,y,0,2*pi,pi/180,radius,fill);
}
void drawPie(double x,double y,double start_angle,double end_angle,double delta_angle,double radius,bool fill)
{
drawArc(x,y,start_angle,end_angle,delta_angle,radius,fill);
if (fill)
{
glBegin(GL_TRIANGLE_FAN);
}
else
{
glBegin(GL_LINES);
}
glVertex2d(x,y);
glVertex2d(x+radius*cos(start_angle),y+radius*sin(start_angle));
if (!fill)
{
glVertex2d(x,y);
}
glVertex2d(x+radius*cos(end_angle),y+radius*sin(end_angle));
glEnd();
}
void myDisplay(void) // plot the sinc function, using world coordinates
{
double pi=acos(-1.0);
glClear(GL_COLOR_BUFFER_BIT);
//画笛卡尔坐标系
glColor3f(1.0,0.0,0.0);
glBegin(GL_LINES);
glVertex2d(-width/2.0,0);
glVertex2d(width/2.0,0);
glEnd();
glBegin(GL_LINES);
glVertex2d(0,height/2.0);
glVertex2d(0,-height/2.0);
glEnd();
glColor3f(1.0,1.0,0.0);
//draw a circle
drawCircle(0,0,100,false);
//draw two arcs
drawArc(0,0,0,pi/2.0,pi/180,200,false);
drawArc(0,0,pi,3*pi/2.0,pi/180,200,true);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glColor4f(0.1,1.0f,0.0,0.5);
//draw two pies
drawPie(0,0,5*pi/4.0,7*pi/4.0,pi/180.0,200,false);
drawPie(0,0,pi/4.0,3*pi/4.0,pi/180.0,200,false);
glDisable(GL_BLEND);
glFlush();
}
void myInit(void)
{
glClearColor(0.0, 0.0, 0.0, 0.0);
glColor3f(0.0f, 0.0f, 1.0f);
glPointSize(4.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(-width/2.0,width/2.0,-height/2.0,height/2.0);
glLineWidth(2.0);
}
int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE |GLUT_RGBA);
glutInitWindowSize(width,height);
glutInitWindowPosition(100,150);
glutCreateWindow("LineInterSectoin");
glutDisplayFunc(myDisplay);
myInit( );
glutMainLoop( );
}