Bresmen's Circle Algorithm for Circle Drawing in all vertices C++ Source Code OpengL VS-2012 Computer Graphics

#include <glut.h>
using namespace std;
void Start_Line( );
void Set_Graphics( int, int );
//void Line_Algo( int, int, int, int );

int main( int argc, char** argv  )
{
   
    glutInit( &argc, argv );
    glutInitWindowSize( 600,600);
    glutInitWindowPosition( 100, 150 );
    glutInitDisplayMode( GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH );
    glutCreateWindow( " Circle Drawing" );
    glutDisplayFunc( Start_Line );
    Set_Graphics( 100, 100 /*window_width, window_height*/ );
    glutMainLoop( );
    return 0;
}

void drawDot (GLint x, GLint y, GLfloat r, GLfloat g, GLfloat b)
{ glColor3f(r,g,b);
  glBegin (GL_POINTS);
      glVertex2i (x,y);
  glEnd();
}

void circlePoints (int x, int y, float r, float g, float b)
{
  drawDot (x,y,r,g,b);
  drawDot (-x,y,r,g,b);
  drawDot (x,-y,r,g,b);
  drawDot (-x,-y,r,g,b);
  drawDot (y,x,r,g,b);
  drawDot (-y,x,r,g,b);
  drawDot (y,-x,r,g,b);
  drawDot (-y,-x,r,g,b);
}

void Circle (int rad, float r, float g, float b)
{ int x,y,d;
 
  x = 0;
  y = rad;
  circlePoints (x,y,r,g,b);
  d = 1 - rad;
  while (y>x)
  {
    if (d < 0)
     { d += 2*x +3;
    x++;}
    else{
     d += 2*(x-y) + 5;
     x++;y--;}
    circlePoints (x,y,r,g,b);
   
   
  }
}
void Set_Graphics( int width, int height )
{
    glClearColor( 1.0, 1.0, 1.0, 0.0 );
    glColor3f( 0.0f, 0.0f, 0.0f );
    glViewport( 0, 0, width, height );
    glMatrixMode( GL_PROJECTION );   
    glLoadIdentity( );
    glEnable( GL_DEPTH_TEST );
    gluPerspective( 45, ( float ) width / height, 1.0, 0 );
    glMatrixMode( GL_MODELVIEW );
    glTranslatef( 0, 0, 5 * ( -height) );
}
void Start_Line( )
{
    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
//    Line_Algo( 5, 8, 29,32 );
    Circle (100,0,0,1);
    glRotatef(1.0, 1.0, 0.0, 0.0);
    glutSwapBuffers( );
}