Forest fire/Java/Graphics

The processing and underlying forest encoding works the same as the text version, but the output is to a JPanel instead. <lang java5>import java.awt.Color; import java.awt.Graphics; import java.util.Arrays; import java.util.LinkedList; import java.util.List;

import javax.swing.JFrame; import javax.swing.JPanel;

public class Fire extends JFrame{ private static final char BURNING = 'w'; //w looks like fire, right? private static final char TREE = 'T'; private static final char EMPTY = '.'; private static final double F = 0.02; private static final double P = 0.01; private static final double TREE_PROB = 0.5; private List<String> land; private JPanel landPanel;

public Fire(List<String> land){ this.land = land; landPanel = new JPanel(){ @Override public void paint(Graphics g) { for(int y = 0; y < Fire.this.land.size();y++){ String row = Fire.this.land.get(y); for(int x = 0; x < row.length();x++){ switch(row.charAt(x)){ case BURNING: g.setColor(Color.RED); break; case TREE: g.setColor(Color.GREEN); break; default: //will catch EMPTY g.setColor(Color.WHITE); } g.fillRect(x*3, y*3, 3, 3); } } } }; //each block in the land is a 3x3 square landPanel.setSize(this.land.get(0).length() * 3, this.land.size() * 3); add(landPanel); setSize(200, 200); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setVisible(true); }

private List<String> process(List<String> land){ List<String> newLand = new LinkedList<String>(); for(int i = 0; i < land.size(); i++){ String rowAbove, thisRow = land.get(i), rowBelow; if(i == 0){//first row rowAbove = null; rowBelow = land.get(i + 1); }else if(i == land.size() - 1){//last row rowBelow = null; rowAbove = land.get(i - 1); }else{//middle rowBelow = land.get(i + 1); rowAbove = land.get(i - 1); } newLand.add(processRows(rowAbove, thisRow, rowBelow)); } return newLand; }

private String processRows(String rowAbove, String thisRow, String rowBelow){ String newRow = ""; for(int i = 0; i < thisRow.length();i++){ switch(thisRow.charAt(i)){ case BURNING: newRow+= EMPTY; break; case EMPTY: newRow+= Math.random() < P ? TREE : EMPTY; break; case TREE: String neighbors = ""; if(i == 0){//first char neighbors+= rowAbove == null ? "" : rowAbove.substring(i, i + 2); neighbors+= thisRow.charAt(i + 1); neighbors+= rowBelow == null ? "" : rowBelow.substring(i, i + 2); if(neighbors.contains(Character.toString(BURNING))){ newRow+= BURNING; break; } }else if(i == thisRow.length() - 1){//last char neighbors+= rowAbove == null ? "" : rowAbove.substring(i - 1, i + 1); neighbors+= thisRow.charAt(i - 1); neighbors+= rowBelow == null ? "" : rowBelow.substring(i - 1, i + 1); if(neighbors.contains(Character.toString(BURNING))){ newRow+= BURNING; break; } }else{//middle neighbors+= rowAbove == null ? "" : rowAbove.substring(i - 1, i + 2); neighbors+= thisRow.charAt(i + 1); neighbors+= thisRow.charAt(i - 1); neighbors+= rowBelow == null ? "" : rowBelow.substring(i - 1, i + 2); if(neighbors.contains(Character.toString(BURNING))){ newRow+= BURNING; break; } } newRow+= Math.random() < F ? BURNING : TREE; } } return newRow; }

public static List<String> populate(int width, int height){ List<String> land = new LinkedList<String>(); for(;height > 0; height--){//height is just a copy anyway StringBuilder line = new StringBuilder(width); for(int i = width; i > 0; i--){ line.append((Math.random() < TREE_PROB) ? TREE : EMPTY); } land.add(line.toString()); } return land; }

public void processN(int n) { for(int i = 0;i < n; i++){ land = process(land); try { Thread.sleep(750); } catch (InterruptedException e) { e.printStackTrace(); } repaint(); } }

public static void main(String[] args){ List<String> land = Arrays.asList(".TTT.T.T.TTTT.T", "T.T.T.TT..T.T..", "TT.TTTT...T.TT.", "TTT..TTTTT.T..T", ".T.TTT....TT.TT", "...T..TTT.TT.T.", ".TT.TT...TT..TT", ".TT.T.T..T.T.T.", "..TTT.TT.T..T..", ".T....T.....TTT", "T..TTT..T..T...", "TTT....TTTTTT.T", "......TwTTT...T", "..T....TTTTTTTT", ".T.T.T....TT..."); Fire fire = new Fire(land); fire.processN(5);

land = populate(50, 50); Fire fire2 = new Fire(land); fire2.processN(10); } }</lang> Output sample: