// Peter Bui
// CSE 40166 Computer Graphics (Fall 2010)
// Lab 1: simple hello, world program
 
#include <cstdlib>

#include <GL/glut.h>

void display();

int 
main(int argc, char *argv[])
{
    glutInit(&argc, argv);	// Initialize GLUT
    glutCreateWindow("hello");	// Create a window
    glutDisplayFunc(display);	// Register display callback
    glutMainLoop();		// Enter main event loop

    return (EXIT_SUCCESS);
}

void 
display()
{
    glClear(GL_COLOR_BUFFER_BIT);   // Erase everything

    glColor3f(1.0, 0.0, 0.0);
    glBegin(GL_POLYGON); {  // Define a polygon	
	glVertex2f(-0.5, -0.5);
	glVertex2f(-0.5,  0.5);
	glVertex2f( 0.5,  0.5);
	glVertex2f( 0.5, -0.5);
    } glEnd();
    
    glColor3f(0.0, 1.0, 0.0);
    glBegin(GL_POLYGON); {  // Define a polygon	
	glVertex2f(-0.25, -0.25);
	glVertex2f(-0.25,  0.25);
	glVertex2f( 0.25,  0.25);
	glVertex2f( 0.25, -0.25);
    } glEnd();

    glFlush(); // Flush all drawings to the screen
}