Display.java

import java.util.LinkedHashMap;
import java.util.Map;
import processing.core.*;

public class Display {
	// Colors used for empty locations.
	private static final int EMPTY_COLOR = 0xFFFFFFFF;

	// Color used for objects that have no defined color.
	private static final int UNKNOWN_COLOR = 0x66666666;

	private PApplet p; // the applet we want to display on

	private int x, y, w, h; // (x, y) of upper left corner of display
	// the width and height of the display

	private float dx, dy; // calculate the width and height of each box
	// in the field display using the size of the field
	// and the width and height of the display

	private int rows, cols;

	// A map for storing colors for participants in the simulation
	private Map<Object, Integer> colors;
	private Map<Object, PImage> images;

	// (x, y) is the upper-left corner of the display in pixels
	// w and h are the width and height of the display in pixels
	public Display(PApplet p, int x, int y, int w, int h) {
		this.x = x;
		this.y = y;
		this.w = w;
		this.h = h;
		this.p = p;

		colors = new LinkedHashMap<Object, Integer>();
		images = new LinkedHashMap<Object, PImage>();
	}

	public void drawGrid(int[][] f) {
		Object piece;
		int numcols = f[0].length;
		int numrows = f.length;

		for (int i = 0; i < numrows; i++) {
			for (int j = 0; j < numcols; j++) {
				piece = f[i][j];
				int pieceColor = getColor(piece);
				PImage pieceImage = getImage(piece);

				if (pieceImage != null) {
					p.image(pieceImage, x + j * dx, y + i * dy, dx, dy);
				} else {
					p.fill(getColor(piece));
					p.rect(x + j * dx, y + i * dy, dx, dy);
				}
			}
		}
	}

	/**
	 * Define a color to be used for a given value in the grid.
	 * 
	 * @param pieceType
	 *          The type of piece in the grid.
	 * @param color
	 *          The color to be used for the given type of piece.
	 */
	public void setColor(Object pieceType, Integer color) {
		colors.put(pieceType, color);
	}

	/**
	 * Define an Image to be used for a given value in the grid.
	 * 
	 * @param pieceType
	 *          The type of piece in the grid.
	 * @param img
	 *          The image to be used for the given type of piece.
	 */
	public void setImage(Object pieceType, PImage img) {
		images.put(pieceType, img);
	}

	/**
	 * Define a color to be used for a given value in the grid.
	 * 
	 * @param pieceType
	 *          The type of piece in the grid.
	 * @param filename
	 *          The file path to the image to be used for the given type of piece.
	 */
	public void setImage(Object pieceType, String filename) {
		PImage img = p.loadImage(filename);
		setImage(pieceType, img);
	}

	/**
	 * @return The color to be used for a given class of animal.
	 */
	private Integer getColor(Object pieceType) {
		Integer col = colors.get(pieceType);
		if (col == null) { // no color defined for this class
			return UNKNOWN_COLOR;
		} else {
			return col;
		}
	}

	private PImage getImage(Object pieceType) {
		PImage img = images.get(pieceType);
		return img;
	}

	// Draw a box at the location
	public void highlightLocation(Location l, TurnOffTheLights g) {
		if (g.isInGrid(l)) {
			p.fill(p.color(50, 200, 50, 150));
			p.rect(xCoordOf(l), yCoordOf(l), dx, dy);
		}
	}

	// return the y pixel value of the upper-left corner of location l
	private float yCoordOf(Location l) {
		return y + l.getRow() * dy;
	}

	// return the x pixel value of the upper-left corner of location l
	private float xCoordOf(Location l) {
		return x + l.getCol() * dx;
	}

	// Return location at coordinates x, y on the screen
	public Location gridLocationAt(float mousex, float mousey) {
		Location l = new Location((int) Math.floor((mousey - y) / dy),
				(int) Math.floor((mousex - x) / dx));
		return l;
	}

	// Return whether (x, y) is over the board or not
	public boolean overBoard(float mx, float my) {
		return (mx >= x && mx <= x + w && my > y && my < y + h);
	}

	public void setNumCols(int numCols) {
		rows = numCols;
		dx = w / rows;
	}

	public void setNumRows(int numRows) {
		cols = numRows;
		dy = h / cols;
	}

	public void initializeWithGame(TurnOffTheLights game) {
		int[][] grid = game.getGrid();
		if (grid == null) {
			System.out
					.println("Your 2d int array grid is null!  Create it by saying grid = new int[___][___] inside your constructor!");
		}
		setNumCols(grid[0].length);
		setNumRows(grid.length);
		System.out.println("Setting disply: # rows is " + grid.length + ", # cols is " + grid[0].length);
	}
}