SWT Browser demo example

3 files changed, 504 insertions, 0 deletions

diff --git a/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/BrowserDemoPlugin.java b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/BrowserDemoPlugin.java
new file mode 100644
index 0000000000..5eb8805c51
--- /dev/null
+++ b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/BrowserDemoPlugin.java
@@ -0,0 +1,49 @@
+package org.eclipse.swt.examples.browser.demos;
+
+import org.eclipse.ui.plugin.*;
+import org.osgi.framework.BundleContext;
+import java.util.*;
+import org.eclipse.core.runtime.*;
+
+public class BrowserDemoPlugin extends AbstractUIPlugin {
+
+	public static BrowserDemoPlugin plugin;
+	ResourceBundle resourceBundle;
+	public static String PLUGIN_PATH = null;
+	
+	public BrowserDemoPlugin() {
+		super();
+		plugin = this;
+		try {
+			resourceBundle = ResourceBundle.getBundle("org.eclipse.swt.examples.browser.demos.BrowserDemoPluginResources");
+		} catch (MissingResourceException x) {
+			resourceBundle = null;
+		}
+	}
+
+	public void start(BundleContext context) throws Exception {
+		super.start(context);
+		PLUGIN_PATH = Platform.resolve(plugin.getBundle().getEntry(".")).toString();
+	}
+
+	public void stop(BundleContext context) throws Exception {
+		super.stop(context);
+	}
+
+	public static BrowserDemoPlugin getDefault() {
+		return plugin;
+	}
+
+	public static String getResourceString(String key) {
+		ResourceBundle bundle = BrowserDemoPlugin.getDefault().getResourceBundle();
+		try {
+			return (bundle != null) ? bundle.getString(key) : key;
+		} catch (MissingResourceException e) {
+			return key;
+		}
+	}
+
+	public ResourceBundle getResourceBundle() {
+		return resourceBundle;
+	}	
+}
diff --git a/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/Pawns.java b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/Pawns.java
new file mode 100644
index 0000000000..cb08f32584
--- /dev/null
+++ b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/Pawns.java
@@ -0,0 +1,222 @@
+package org.eclipse.swt.examples.browser.demos;
+
+public class Pawns {
+
+	/* Current board representation in compacted form */
+	byte[] game = new byte[64];
+	/* Best move */
+	int bestIndex = -1;
+	/* Related best score */
+	int bestScore = Integer.MIN_VALUE;
+	/* Estimated strategic value of each cell based on proximity to walls */
+	static int[] gameWallWeight = new int[64];
+	Thread thread = null;
+	boolean threadStop = false;
+	
+	final static byte EMPTY = 0;
+	final static byte WHITE = 1;
+	final static byte BLACK = 2;
+	final static byte WALL = 3;
+	
+public Pawns() {
+}
+
+/* Provide the current game and ignitiate the search of the best move for the given type
+ * Must return immediately as it will be called from the UI thread.
+ * The UI thread will fetch the best move any time thereafter.
+ */
+public void playRequest(byte[][] game, int type) {
+	threadStop = true;
+	synchronized (this) {
+		bestIndex = -1;
+		bestScore = Integer.MIN_VALUE;
+		convert(game, this.game);
+		initPawnBorders(this.game, gameWallWeight);
+		/* Quickly compute a legal move */
+		for (int i = 0; i < this.game.length; i++) {
+			if (this.game[i] == EMPTY) {
+				bestIndex = i;
+				break;
+			}
+		}
+		new Thread() {
+			public void run() {
+				synchronized(Pawns.this) {
+					threadStop = false;
+					int[] result = new int[2];
+					/* if long time, must check for threadStop and exit early */ 
+					evalBest(Pawns.this.game, BLACK, 2, result);
+					bestIndex = result[0];
+					bestScore = result[1];
+				}
+			}
+		}.start();
+	}
+}
+
+/* Fetch best move in natural coordinates for the board previously given in
+ * the call to playRequest.
+ */
+public void getBestMove(int[] point) {
+	convert(bestIndex, point);
+	threadStop = true;
+}
+
+/* Given an expanded representation of the board, format internal compact mode */
+static void convert(byte[][] board, byte[] g) {
+	for (int i = 0; i < board.length; i++) System.arraycopy(board[i], 0, g, i * 8, 8);
+}
+/* Update given compact model based on player move in natural coordinates */
+static void set(byte[] g, int x, int y, byte type) {
+	g[x*8+y] = type;
+}
+/* Given an index in compact representation, return natural coordinates */
+static void convert(int index, /*out [0] x [1] y */int[] point) {
+	point[0] = index / 8;
+	point[1] = index % 8;
+}
+/* Given an index into the compact model and the neighbour code,
+ * return the index of the corresponding neighbour index.
+ * Returns -1 if there is no neighbour.
+ * 
+ * Neighbour code for the index X
+ * 0 1 2
+ * 3 X 4
+ * 5 6 7 
+ */
+static int getNeighbourIndex(byte[] g, int index, int neighbour) {
+	if (index < 0 || index >= g.length) return -1;
+	int result = -1;
+	switch (neighbour) {
+		case 0: result = index < 8 || index % 8 == 0 ? -1 : index - 9; break;
+		case 1: result = index < 8 ? -1 : index - 8; break;
+		case 2: result = index < 8 || index % 8 == 7 ? -1 : index - 7; break;
+		case 3: result = index % 8 == 0 ? -1 : index - 1; break;
+		case 4: result = index % 8 == 7 ? -1 : index + 1; break;
+		case 5: result = index % 8 == 0 || index >= 56 ? -1 : index + 7; break;
+		case 6: result = index >= 56 ? -1 : index + 8; break;
+		case 7: result = index % 8 == 7 || index >= 56 ? -1 : index + 9; break;
+	}
+	return result;
+}
+/* Make the player type play at index on given compact board 
+ * Compute all pawns that must be reversed.
+ */
+static void play(byte[] g, int index, byte type) {
+	byte opponentType = type == WHITE ? BLACK : WHITE;
+	for (int neighbour = 0; neighbour <= 7; neighbour++) {
+		int nIndex = getNeighbourIndex(g, index, neighbour);
+		int[] reversiIndeces = new int[6];
+		int nReversi = 0;
+		while (nIndex != -1 && nReversi < 6 && g[nIndex] == opponentType) {
+			reversiIndeces[nReversi] = nIndex;
+			nReversi++;
+			nIndex = getNeighbourIndex(g, nIndex, neighbour);			
+		}
+		if (nReversi > 0 && nIndex != -1 && g[nIndex] == type) {
+			for (int i = 0; i < nReversi; i++) g[reversiIndeces[i]] = type;
+		}
+	}
+	g[index] = type;
+}
+/* Evaluate the given compact model based on pawns distribution 
+ * High means white has advantage. Below zero means black has advantage.
+ */
+static int eval(byte[] g) {
+	int cntWhite = 0, cntBlack = 0, cntEmpty = 0;
+	int cntWhiteWallAdvantage = 0, cntBlackWallAdvantage = 0;
+	for (int i = 0; i < 64; i++) {
+		if (g[i] == WHITE) {
+			cntWhite++;
+			cntWhiteWallAdvantage += gameWallWeight[i];
+		}
+		else if (g[i] == BLACK) {
+			cntBlack++;
+			cntBlackWallAdvantage += gameWallWeight[i];
+		}
+		else if (g[i] == EMPTY) cntEmpty++;
+	}
+	if (cntEmpty == 0) {
+		if (cntWhite > cntBlack) return Integer.MAX_VALUE; /* White wins */
+		if (cntWhite < cntBlack) return Integer.MIN_VALUE; /* Black wins */
+		return 0; /* Stalemate */
+	}
+	return cntWhite + cntWhiteWallAdvantage - cntBlack - cntBlackWallAdvantage;
+}
+
+/* Recognize pawns protected by walls or borders 
+ * TBD - note this should be called only once for each cell and stored
+ * in a separate byte[] gWallGain
+ * */
+static void initPawnBorders(byte[] g, int[] gameWallWeight) {
+	/* A pawn has 8 neighbours on 4 axes.
+	 * Strategic pawns have one side of each axis protected by a wall and the other
+	 * side not closed by a wall.
+	 * A pawn cannot be reversed when each of its 4 axes are protected by a wall on
+	 * one side. Pawns that have more than 4 walls are less interesting since they
+	 * are not open enough to the board.
+	 * 
+	 * Nbr walls, nbr axis covered, estimated value
+	 * 0 n/a 0
+	 * 1 1 2
+	 * 2 1 1
+	 * 2 2 6
+	 * 3 2 4
+	 * 4 2 2
+	 * 3 3 9
+	 * 4 3 8
+	 * 4 4 16
+	 * 5 4 14
+	 * 6 4 9
+	 * 7 4 6
+	 * 8 4 0
+	 */
+	int[] nTypes = new int[8];
+	for (int i = 0; i < 64; i++) {
+		int nWalls = 0;
+		int nAxis = 0;
+		for (int n = 0; n < 8; n++) {
+			int nIndex = getNeighbourIndex(g, i, n);
+			nTypes[n] = nIndex != -1 ? g[nIndex] : WALL;
+			if (nTypes[n] == WALL) nWalls++;
+		}
+		int score = nWalls;
+		if (nWalls > 0) {
+			if (nTypes[0] == WALL || nTypes[7] == WALL) nAxis++;
+			if (nTypes[1] == WALL || nTypes[6] == WALL) nAxis++;
+			if (nTypes[2] == WALL || nTypes[5] == WALL) nAxis++;
+			if (nTypes[4] == WALL || nTypes[3] == WALL) nAxis++;
+			switch (nAxis) {
+				case 4: switch (nWalls) { case 4: score = 16; break; case 5: score = 14; break; case 6: score = 9; case 7: score = 6; break; case 8: score = 0; break;}; break;
+				case 3: switch (nWalls) { case 3: score = 9; break; case 4: score = 8;}; break;
+				case 2: switch (nWalls) { case 2: score = 6; break; case 3: score = 4; break; case 4: score = 2; }; break;
+				case 1: switch (nWalls) { case 1: score = 2; break; case 2: score = 1; break;}; break;
+			};
+		}
+		gameWallWeight[i] = score;
+	}
+}
+
+/* Evaluate the best move for player type for the given board, doing a depth 1 search */
+static void evalBest(byte[] g, byte type, int depth, /* out [0] best move, [1] minimax */int[] result) {
+	byte[] tmp = new byte[64];
+	byte opponentType = type == WHITE ? BLACK : WHITE;
+	result[0] = -1; result[1] = Integer.MIN_VALUE;
+	for (int i = 0; i < 64; i++) {
+		if (g[i] == EMPTY) {
+			System.arraycopy(g, 0, tmp, 0, 64);
+			play(tmp, i, type);
+			int score = eval(tmp);
+			if (depth > 1) {
+				int[] tmpResult = new int[2];
+				evalBest(tmp, opponentType, depth - 1, tmpResult);
+				score = tmpResult[1];
+			}
+			if ((type == WHITE && score > result[1]) || (type == BLACK && score < result[1]) || result[0] == -1) {
+				result[0] = i;
+				result[1] = score;
+			}
+		}
+	}
+}
+}
\ No newline at end of file
diff --git a/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/views/BrowserDemoView.java b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/views/BrowserDemoView.java
new file mode 100644
index 0000000000..b56d49b02b
--- /dev/null
+++ b/examples/org.eclipse.swt.examples.browser.demos/src/org/eclipse/swt/examples/browser/demos/views/BrowserDemoView.java
@@ -0,0 +1,233 @@
+package org.eclipse.swt.examples.browser.demos.views;
+
+import org.eclipse.ui.part.*;
+import org.eclipse.jface.dialogs.MessageDialog;
+import org.eclipse.swt.*;
+import org.eclipse.swt.browser.*;
+import org.eclipse.swt.widgets.*;
+import org.eclipse.swt.examples.browser.demos.*;
+
+public class BrowserDemoView extends ViewPart {
+	Browser browser = null;
+	ReversiListener reversiListener;
+
+	final static int TYPE_WELCOME = 1;
+	final static int TYPE_START = 2;
+	final static int TYPE_BOARD = 3;
+	final static int TYPE_BOARD_OVER = 4;
+
+	final static String URL = "http://www.org.eclipse.swt.examples.browser.demos.pawns/";
+	static String PLUGIN_PATH = BrowserDemoPlugin.PLUGIN_PATH;
+	static String CSS_FOLDER = "css1";
+	static String URL_CSS = PLUGIN_PATH+CSS_FOLDER+"/style.css";
+	static String URL_WELCOME =PLUGIN_PATH+CSS_FOLDER+"/welcome.html";
+
+	final static String ACTION_START_2_PLAYERS = "actionstart2players";
+	final static String ACTION_START_1_PLAYER = "actionstart1player";
+	final static String ACTION_WHITE = "actionwhite";
+	final static String ACTION_BLACK = "actionblack";
+	final static String ACTION_BLACK_COMPUTER = "actionblackcomputer";
+	final static String ACTION_THEME = "actiontheme";
+
+	static byte[][] game = null;
+	static boolean isWhite = true;
+	static int cntWhite = 0, cntBlack = 0;
+	static boolean computer = false;
+	static int cx, cy;
+	final static byte EMPTY = 0;
+	final static byte WHITE = 1;
+	final static byte BLACK = 2;
+	final static byte WALL = 3;
+	
+	static Pawns ttr = null;
+	static int[] move = new int[2];
+	
+	public BrowserDemoView() {
+	}
+	public void createPartControl(Composite parent) {
+		try {
+			browser = new Browser(parent, SWT.NONE);
+		} catch (SWTError e) {
+			e.printStackTrace();
+			return;
+		}
+		reversiListener = new ReversiListener();
+		browser.addLocationListener(reversiListener);
+		browser.setUrl(URL_WELCOME);
+
+	}
+	private void showMessage(String message) {
+		MessageDialog.openInformation(
+			browser.getShell(),
+			"Browser Demo",
+			message);
+	}
+	public void setFocus() {
+		browser.setFocus();
+	}
+	
+	static String getHtml(int type) {
+		String html = null;
+		switch (type) {
+		case TYPE_BOARD:
+		case TYPE_BOARD_OVER: {
+			html = "<html><header><link rel=\"stylesheet\" type=\"text/css\" href=\""+URL_CSS+"\"></header><body><div class=\"board\"><table><tbody>";
+			String classPlayerWhite = "playerwhite", classPlayerBlack = "playerblack";
+			if (type == TYPE_BOARD_OVER) {
+				if (cntWhite > cntBlack) {
+					classPlayerWhite += " winner";
+					classPlayerBlack += " loser";
+				} else {
+					classPlayerWhite += " loser";
+					classPlayerBlack += " winner";
+				}
+			}
+			for (int i = 0; i < game.length; i++) {
+				html += "<tr>";
+				for (int j = 0; j < game[0].length; j++) {
+					switch (game[i][j]) {
+						case EMPTY: html += "<td class=\""+(isWhite ? "whitelink" : "blacklink")+"\"><a href=\""+URL+(isWhite ? ACTION_WHITE : computer ? ACTION_BLACK_COMPUTER : ACTION_BLACK)+"/xx"+i+"yy"+j+"\" class=\"empty\"/></td>"; break;
+						case WHITE: html += "<td class=\"white\"/>"; break;
+						case BLACK: html += "<td class=\"black\"/>"; break;
+						case WALL: html += "<td class=\"wall\"/>"; break;
+					}
+				}
+				html +="</tr>";
+			}
+			html += "</tbody></table></div>";
+			html += "<div class=\""+classPlayerWhite+"\">"+cntWhite+"</div>";
+			html += "<div class=\""+classPlayerBlack+"\">"+cntBlack+"</div>";
+			html += "</body></html>";
+			break;
+		}
+		}
+		return html;
+	}
+
+	public class ReversiListener implements LocationListener {
+		public void changed(LocationEvent e) {
+		}
+		public void changing(LocationEvent e) {
+			try {
+			final Browser browser = (Browser)e.widget;
+			if (e.location.indexOf(ACTION_START_1_PLAYER) != -1 || e.location.indexOf(ACTION_START_2_PLAYERS) != -1) {
+				computer = e.location.indexOf(ACTION_START_1_PLAYER) != -1;
+				game = new byte[8][8];
+				if (computer) ttr = new Pawns();
+				for (int i = 0; i < 5; i++) game[(int)(Math.random()*game.length)][(int)(Math.random()*game[0].length)] = WALL;
+				e.display.asyncExec(new Runnable() {
+					public void run() {
+						browser.setText(getHtml(TYPE_BOARD));
+				}});
+				e.doit = false;
+				return;
+			}
+			if (e.location.indexOf(ACTION_THEME) != -1) {
+				int index = e.location.indexOf(ACTION_THEME) + ACTION_THEME.length() + 1;
+				CSS_FOLDER = e.location.substring(index, index + 4);
+				URL_CSS = PLUGIN_PATH+CSS_FOLDER+"/style.css";
+				URL_WELCOME = PLUGIN_PATH+CSS_FOLDER+"/welcome.html";
+				e.display.asyncExec(new Runnable() {
+					public void run() {
+						browser.setUrl(URL_WELCOME);
+				}});
+				e.doit = false;
+				return;
+			}
+			byte player = EMPTY;
+			if (e.location.indexOf(ACTION_WHITE) != -1) player = WHITE;
+			else if (e.location.indexOf(ACTION_BLACK) != -1) player = BLACK;
+			if (player != EMPTY) {
+				int index = e.location.indexOf("xx") + 2;
+				int x = Integer.parseInt(e.location.substring(index, index + 1));
+				index = e.location.indexOf("yy") + 2;
+				int y = Integer.parseInt(e.location.substring(index, index + 1));
+				boolean hasMore = add(x, y, player);
+				isWhite = player != WHITE;
+				browser.setText(getHtml(hasMore ? TYPE_BOARD : TYPE_BOARD_OVER));
+				if (computer && hasMore && !isWhite) play(e.display, browser, 5000);
+				e.doit = false;
+			}
+			}catch (Exception e1 ) {
+				e1.printStackTrace();
+			}
+		}
+	}
+
+	public static boolean add(int x, int y, byte color) {
+		game[x][y] = color;
+		int cnt = Math.min(x, y), n = 0;
+		int other_color = color == WHITE ? BLACK : WHITE;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x-d][y-d] == other_color) n++;
+			else if (game[x-d][y-d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x-d][y-d] = color; break; }
+		}
+		cnt = Math.min(game.length - 1 - x, game[0].length - 1 - y); n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x+d][y+d] == other_color) n++;
+			else if (game[x+d][y+d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x+d][y+d] = color; break; }
+		}
+		cnt = Math.min(game.length - 1 - x, y); n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x+d][y-d] == other_color) n++;
+			else if (game[x+d][y-d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x+d][y-d] = color; break; }
+		}
+		cnt = Math.min(x, game[0].length - 1 - y); n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x-d][y+d] == other_color) n++;
+			else if (game[x-d][y+d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x-d][y+d] = color; break; }
+		}
+		cnt = y; n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x][y-d] == other_color) n++;
+			else if (game[x][y-d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x][y-d] = color; break; }
+		}
+		cnt = game[0].length - 1 - y; n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x][y+d] == other_color) n++;
+			else if (game[x][y+d] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x][y+d] = color; break; }
+		}
+		cnt = x; n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x-d][y] == other_color) n++;
+			else if (game[x-d][y] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x-d][y] = color; break; }
+		}
+		cnt = game.length - 1 - x; n = 0;
+		for (int d = 1; d <= cnt; d++) {
+			if (game[x+d][y] == other_color) n++;
+			else if (game[x+d][y] != color) break;
+			else { if (n > 0) for (d = 1; d <= n; d++) game[x+d][y] = color; break; }
+		}
+
+		boolean hasMore = false;
+		cntWhite = 0; cntBlack = 0;
+		for (int i = 0; i < game.length; i++)
+			for (int j = 0; j < game[0].length; j++) {
+				switch (game[i][j]) {
+					case EMPTY: hasMore = true; break;
+					case WHITE: cntWhite++; break;
+					case BLACK: cntBlack++; break;
+				}
+			}
+		return hasMore;
+	}
+	
+	public static void play(final Display display, final Browser browser, int delay) {
+		ttr.playRequest(game, BLACK);
+		display.timerExec(3000, new Runnable() {
+				public void run() {
+					ttr.getBestMove(move);
+					boolean hasMore = add(move[0], move[1], BLACK);
+					isWhite = true;
+					browser.setText(getHtml(hasMore ? TYPE_BOARD : TYPE_BOARD_OVER));
+				}
+		});
+	}
+}
\ No newline at end of file