Someone

//IN BOOK - #include "OpenGL.h"
#include "../common/openglsb.h"



void RenderScene()
{
	glClear(GL_COLOR_BUFFER_BIT);
	glColor3f(1.0f, 0.0f, 0.0f);
	
	glRectf(-25.0f, 25.0f, 25.0f, -25.0f);
//	glutSwapBuffers(); 
	glFlush();
}

void SetupRC()
{
	glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
}

void ChangeSize(GLsizei width, GLsizei height)
{
	GLfloat aspectRatio;
	
    // Prevent a divide by zero
	if (height == 0)
		height = 1;

    // Set viewport to window dimensions
    glViewport(0, 0, width, height);
	
    // Reset coordinate system
    glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

    aspectRatio = (GLfloat) width / (GLfloat) height;

    if (width <= height)
        glOrtho(-100.0, -100.0, -100 / aspectRatio, 100.0 / aspectRatio, 1.0, -1.0);
    else
        glOrtho(-100.0 * aspectRatio, -100.0 * aspectRatio, -100, 100.0, 1.0, -1.0);
    
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}

int main(int argc, char* argv[])
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
//	glutInitWindowSize(800, 600);
    glutCreateWindow("Rect");
    glutDisplayFunc(RenderScene);
//    glutReshapeFunc(ChangeSize);
	SetupRC();
	glutMainLoop();

	return 0;
}