Checker Board Pattern using C++

checkers.cpp

/*
	The Code Below is used to develop a Checker Board Pattern.

	1. Start with Identifying the First Square
	2. Put in the coordinates for the First Square
	3. Create a for-loop to to create squares at the same time
	4. Introduce a variable to help keep track of the color. Using an IF Statement.
	5. Introduce an outer for-loop to cater for the y - axis.
*/


#include <windows.h> // for MS Windows
#include <GL/glut.h> // GLUT, include glu.h and gl.h




/* Initialize OpenGL Graphics */

void initGL() {
  
// Set "clearing" or background color
  glClearColor(1.0f, 1.0f, 1.0f, 1.0f); 

  glMatrixMode(GL_PROJECTION);	 
  glLoadIdentity();
  gluOrtho2D(0.0, 640.0, 0.0, 480.0);

}


void display() {
	glClear(GL_COLOR_BUFFER_BIT); 


	//initialize the variables.
	GLint x = 50;
	GLint y = 50;
	GLint colorCode = 1;

for(y = 50; y <= 350; y += 50) {

	for(x = 50; x <= 350; x += 50) {
		
		//helps toggle the color.
		if (colorCode == 1) {
			glColor3f(0.0, 0.0, 0.0);
			colorCode = 0;
		}	 
		else {
			glColor3f(1.0, 1.0, 1.0);
			colorCode = 1;
		}
		
		//identify the first square
		glBegin(GL_QUADS); 
		glVertex2i(x, y);
		glVertex2i(x, y + 50);
		glVertex2i(x + 50, y + 50);
		glVertex2i(x + 50, y);
		glEnd();

	}

}


	glFlush(); // Render now
}




/* Main function: GLUT runs as a console application starting at main() */
int main(int argc, char** argv) {
	glutInit(&argc, argv); // Initialize GLUT
	glutCreateWindow("Understandable Checkers"); // Create window with the given title
	glutInitWindowSize(640, 480); // Set the window's initial width & height
	glutInitWindowPosition(50, 50); // Position the window's initial top-left corner
	glutDisplayFunc(display); // Register callback handler for window re-paint event
	initGL(); // Our own OpenGL initialization
	glutMainLoop(); // Enter the event-processing loop
	return 0;
}