#include <GL/glut.h>
void init (void)
{
glClearColor (0.0, 0.0, 0.0, 0.0); //Set display-window color //or can use glClearIndex (index);
glMatrixMode (GL_PROJECTION);
gluOrtho2D (0.0, 200.0, 0.0, 150.0);
}
void lineSegment (void)
{
glClear (GL_COLOR_BUFFER_BIT);
glColor3f (0.0, 1.0, 0.0);
glBegin(GL_QUADS); // Draw A Quad
glVertex3f(-1.0f, 1.0f, 0.0f); // Top Left
glVertex3f( 1.0f, 1.0f, 0.0f); // Top Right
glVertex3f( 1.0f,-1.0f, 0.0f); // Bottom Right
glVertex3f(-1.0f,-1.0f, 0.0f); // Bottom Left
glEnd(); // Done Drawing The Quad
glFlush ();
}
void main (int argc, char** argv)
{
glutInit (&argc, argv);
glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition (50, 100);
glutInitWindowSize (400, 300);
glutCreateWindow (“An example OpenGL Program”);
init ();
glutDisplayFunc (lineSegment);
glutMainLoop ();
}