This applet demonstrates how reinforcement
learning can be used to train an agent to play
a simple game. In this case the game is Cat and
Mouse- the mouse tries to get to the cheese
and back to it's hole, the cat tries to catch the mouse.", USAGE_MESSAGE = "
You can train the agent by selecting the Train tab. At
any time you can select the Play tab to see how
well the agent is performing! Of course, the more
training, the better the chance the mouse
has of surviving :)";
// train panel components
public static final String START="S", CONT_CHECK="C";
final String SETTINGS_TEXT = "These settings adjust some of the internal workings of the reinforcement learning algorithm.",
SETTINGS_TEXT2 = "Please see the web pages for more details on what the parameters do.";
JTextField alpha, gamma, epsilon, epochs, penalty, reward;
JButton startTraining, stopTraining;
JRadioButton softmax, greedy, sarsa, qlearn;
JProgressBar progress;
JLabel learnEpochsDone;
// play panel components
JButton startbutt, stopbutt, pausebutt;
boardPanel bp;
public int mousescore=0, catscore =0;
JLabel catscorelabel, mousescorelabel;
final String MS_TEXT = "Mouse Score:", CS_TEXT = "Cat Score:";
JSlider speed, smoothSlider;
Image catImg, mouseImg;
chartPanel graphPanel;
JLabel winPerc;
boardObject cat, mouse, cheese, back, hole, wall;
public SwingApplet() {
getRootPane().putClientProperty("defeatSystemEventQueueCheck",Boolean.TRUE);
}
public void init() {
// load images
catImg = getImage(getCodeBase(), "cat.gif");
mouseImg = getImage(getCodeBase(), "mouse.gif");
Image wallImg = getImage(getCodeBase(), "wall.gif");
Image cheeseImg = getImage(getCodeBase(), "cheese.gif");
Image floorImg = getImage(getCodeBase(), "floor.gif");
/* Image catImg = getImage(ClassLoader.getSystemResource("cat.gif"));
Image mouseImg = getImage(ClassLoader.getSystemResource("mouse.gif"));
Image wallImg = getImage(ClassLoader.getSystemResource("wall.gif"));
Image cheeseImg = getImage(ClassLoader.getSystemResource("cheese.gif"));*/
// set up board objects
cat = new boardObject(catImg);
mouse = new boardObject(mouseImg);
cheese = new boardObject(cheeseImg);
back = new boardObject(floorImg);
hole = new boardObject(Color.orange);
wall = new boardObject(wallImg);
// setup content panes
tabbedPane = new JTabbedPane();
//instructions = makeInstructions();
worldPanel = makeWorldPanel();
playPanel = makePlayPanel();
trainPanel = makeTrainPanel();
tabbedPane.addTab("World", worldPanel);
tabbedPane.addTab("Play", playPanel);
//tabbedPane.addTab("Instructions", instructions);
tabbedPane.addTab("Train", trainPanel);
tabbedPane.setSelectedIndex(0);
// disable panes until world created
tabbedPane.setEnabledAt(1,false);
tabbedPane.setEnabledAt(2,false);
// set up controls
//setContentPane(new JPanel());
//getContentPane().add(tabbedPane);
getContentPane().add(tabbedPane);
}
public void worldInit(int xdim, int ydim, int numwalls) {
trainWorld = new CatAndMouseWorld(xdim, ydim,numwalls);
gameInit(xdim,ydim);
}
public void worldInit(boolean[][] givenWalls) {
int xdim = givenWalls.length, ydim = givenWalls[0].length;
trainWorld = new CatAndMouseWorld(xdim, ydim,givenWalls);
gameInit(xdim,ydim);
}
private void gameInit(int xdim, int ydim) {
// disable this pane
tabbedPane.setEnabledAt(0,false);
playWorld = new CatAndMouseWorld(xdim, ydim,trainWorld.walls);
bp.setDimensions(xdim, ydim);
rlc = new RLController(this, trainWorld, DELAY);
rl = rlc.learner;
rlc.start();
game = new CatAndMouseGame(this, DELAY, playWorld, rl.getPolicy());
game.start();
// set text fields on panels
penalty.setText(Integer.toString(trainWorld.deathPenalty));
reward.setText(Integer.toString(trainWorld.cheeseReward));
alpha.setText(Double.toString(rl.getAlpha()));
gamma.setText(Double.toString(rl.getGamma()));
epsilon.setText(Double.toString(rl.getEpsilon()));
// enable other panes
tabbedPane.setEnabledAt(1,true);
tabbedPane.setEnabledAt(2,true);
// switch active pane
tabbedPane.setSelectedIndex(1);
// set first position on board
updateBoard();
}
// this method is triggered by SwingUtilities.invokeLater in other threads
public void run() { updateBoard(); }
/************ general functions ****************/
public void updateBoard() {
// update score panels
mousescorelabel.setText(MS_TEXT+" "+Integer.toString(mousescore));
catscorelabel.setText(CS_TEXT+" "+Integer.toString(catscore));
if (game.newInfo) {
updateScore();
game.newInfo = false;
}
// update progress info
progress.setValue(rlc.epochsdone);
learnEpochsDone.setText(Integer.toString(rlc.totaldone));
if (rlc.newInfo) endTraining();
// update game board
bp.clearBoard();
// draw walls
boolean[][] w = game.getWalls();
for (int i=0; i