Open GL Program to perform various Mouse Events

#include<GL/gl.h>
#include<GL/glut.h>
void display()
{
   glClear(GL_COLOR_BUFFER_BIT );
   glBegin(GL_TRIANGLES);
   glVertex2f(0.0,0.4);
   glVertex2f(-0.4,-0.4);
   glVertex2f(0.4,-0.4);
   glEnd();
   glFlush();
}

void processMouse(int button,int state,int x,int y)
{
     if(button==GLUT_LEFT_BUTTON && state==GLUT_DOWN)
     {
       glColor3f(1.0,0.0,0.0);
     }
     else if(button==GLUT_RIGHT_BUTTON && state==GLUT_DOWN)
     {
          glColor3f(0.0,1.0,0.0);
     }
     else
     {
          glColor3f(1.0,1.0,0.0);
     }
     glutPostRedisplay();
}

void processActiveMotionMouse(int x,int y)
{
     if(x<300)
     {
       glColor3f(1.0,0.0,0.0);
     }
     else if(x>300)
     {
          glColor3f(0.0,1.0,0.0);
     }
     else
     {
          glColor3f(1.0,1.0,0.0);
     }
     glutPostRedisplay();
}
void processPassiveMotionMouse(int x,int y)
{
     if(x<300)
     {
       glColor3f(1.0,0.0,0.0);
     }
     else if(x>300)
     {
          glColor3f(0.0,1.0,0.0);
     }
     else
     {
          glColor3f(1.0,1.0,0.0);
     }
     glutPostRedisplay();
}
void processEntryMouse(int state)
{
     if(state==GLUT_LEFT)
     {
       glColor3f(1.0,0.0,0.0);
     }
     else
     {
          glColor3f(1.0,1.0,0.0);
     }
     glutPostRedisplay();
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB );
   glutInitWindowSize (500, 500);
   glutInitWindowPosition (150, 150);
   glutCreateWindow ("Mouse Events");
   glutDisplayFunc(display);
   glutMouseFunc(processMouse);
   //glutMotionFunc(processActiveMotionMouse);
   //glutPassiveMotionFunc(processPassiveMotionMouse);
   //glutEntryFunc(processEntryMouse);
   glutMainLoop();
   return 0;
}




                                                    OUTPUT