CACanvas.java

package edu.neu.csye6200.ca;


import java.util.logging.Logger;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JPanel;

/**
 * A sample canvas that draws a rainbow of squares
 * @author MMUNSON
 */
public class CACanvas extends JPanel {

	private static final long serialVersionUID = 1L;
	private Logger log = Logger.getLogger(CACanvas.class.getName());
    private int cellSize = 20;
    private Color col = null;
    private long counter = 0L;
	
    /**
     * CellAutCanvas constructor
     */
	public CACanvas() {
		col = Color.WHITE;
	}

	/**
	 * The UI thread calls this method when the screen changes, or in response
	 * to a user initiated call to repaint();
	 */
	public void paint(Graphics g) {
		drawCellularAutomaton(g); // Our Added-on drawing
    }
	
	/**
	 * Draw the CA graphics panel
	 * @param g
	 */
	public void drawCellularAutomaton(Graphics g) {
		log.info("Drawing cell automation " + counter++);
		Graphics2D g2d = (Graphics2D) g;
		Dimension size = getSize();
		
		g2d.setColor(Color.BLACK);
		g2d.fillRect(0, 0, size.width, size.height);
		
		g2d.setColor(Color.RED);
		g2d.drawString("Cellular Automaton 2D", 10, 15);
		
		int maxRows = size.height / cellSize;
		int maxCols = size.width / cellSize;
		for (int j = 0; j < maxRows; j++) {
		   for (int i = 0; i < maxCols; i++) {
			   int redVal = validColor(i*5);
			   int greenVal = validColor(255-j*5);
			   int blueVal = validColor((j*5)-(i*2));
			   col = new Color(redVal, greenVal, blueVal);
			   // Draw box, one pixel less to create a black outline
			   paintRect( g2d, i*cellSize, j*cellSize + 20, cellSize-1, col); 
		   }
		}
	}
	
	/*
	 * A local routine to ensure that the color value is in the 0 to 255 range;
	 */
	private int validColor(int colorVal) {
		if (colorVal > 255)
			colorVal = 255;
		if (colorVal < 0)
			colorVal = 0;
		return colorVal;
	}
	
	/*
	 * A convenience routine to
	 *  set the color and paint a square
	 * @param g2d the graphics context
	 * @param x horizontal offset in pixels
	 * @param y vertical offset in pixels
	 * @param size the square size in pixels
	 * @param color the color to draw
	 */
	private void paintRect(Graphics2D g2d, int x, int y, int size, Color color) {
		g2d.setColor(color);
		g2d.fillRect(x, y, size, size);
	}
	
}