/*
 * File: Checkerboard2.java
 * ------------------------
 *
 * This is the ACM Java Task Force Checkerboard.java acm.graphics
 * example, extended to include a few more graphics operations.
 * Here's the original description:
 *
 * -----
 * This program draws a checkerboard.  The dimensions of the
 * checkerboard is specified by the constants NROWS and
 * NCOLUMNS, and the size of the squares is chosen so
 * that the checkerboard fills the available vertical space.
 * -----
 *
 * Modifications by L. McCann 2007/02/11
 */

import acm.graphics.*;
import acm.program.*;
import acm.util.*;      // JTFTools
import java.awt.*;      // Colors

public class Checkerboard2 extends GraphicsProgram {

/** Runs the program */
    public void run() {

        final int NUM_COLORS = 4;

        double          sqSize = (double) getHeight() / NROWS;
        Color[]         color = new Color[NUM_COLORS];
        RandomGenerator rand = new RandomGenerator();

        color[0] = Color.BLACK;
        color[1] = Color.RED;
        color[2] = Color.BLUE;
        color[3] = Color.GREEN;

        for (int i = 0; i < NROWS; i++) {
            for (int j = 0; j < NCOLUMNS; j++) {
                double x = j * sqSize;
                double y = i * sqSize;
                GRect sq = new GRect(x, y, sqSize, sqSize);
                if ((i + j) % 2 != 0) {
                    sq.setColor(color[rand.nextInt(NUM_COLORS)]);
                    sq.setFilled(true);
                    add(sq);  // places the GRect obj on the canvas
                }
                JTFTools.pause(100);   // pause for a tenth of a second
            }
        }
    }  // run

/* Private constants */
    private static final int NROWS = 8;     /* Number of rows    */
    private static final int NCOLUMNS = 8;  /* Number of columns */

}