samegame.js Example File

declarative/tutorials/samegame/samegame4/content/samegame.js
 /* This script file handles the game logic */
 var maxColumn = 10;
 var maxRow = 15;
 var maxIndex = maxColumn * maxRow;
 var board = new Array(maxIndex);
 var component;
 var scoresURL = "";
 var gameDuration;

 //Index function used instead of a 2D array
 function index(column, row) {
     return column + (row * maxColumn);
 }

 function startNewGame() {
     //Delete blocks from previous game
     for (var i = 0; i < maxIndex; i++) {
         if (board[i] != null)
             board[i].destroy();
     }

     //Calculate board size
     maxColumn = Math.floor(gameCanvas.width / gameCanvas.blockSize);
     maxRow = Math.floor(gameCanvas.height / gameCanvas.blockSize);
     maxIndex = maxRow * maxColumn;

     //Close dialogs
     nameInputDialog.hide();
     dialog.hide();

     //Initialize Board
     board = new Array(maxIndex);
     gameCanvas.score = 0;
     for (var column = 0; column < maxColumn; column++) {
         for (var row = 0; row < maxRow; row++) {
             board[index(column, row)] = null;
             createBlock(column, row);
         }
     }

     gameDuration = new Date();
 }

 function createBlock(column, row) {
     if (component == null)
         component = Qt.createComponent("content/BoomBlock.qml");

     // Note that if Block.qml was not a local file, component.status would be
     // Loading and we should wait for the component's statusChanged() signal to
     // know when the file is downloaded and ready before calling createObject().
     if (component.status == Component.Ready) {
         var dynamicObject = component.createObject(gameCanvas);
         if (dynamicObject == null) {
             console.log("error creating block");
             console.log(component.errorString());
             return false;
         }
         dynamicObject.type = Math.floor(Math.random() * 3);
         dynamicObject.x = column * gameCanvas.blockSize;
         dynamicObject.y = row * gameCanvas.blockSize;
         dynamicObject.width = gameCanvas.blockSize;
         dynamicObject.height = gameCanvas.blockSize;
         dynamicObject.spawned = true;
         board[index(column, row)] = dynamicObject;
     } else {
         console.log("error loading block component");
         console.log(component.errorString());
         return false;
     }
     return true;
 }

 var fillFound; //Set after a floodFill call to the number of blocks found
 var floodBoard; //Set to 1 if the floodFill reaches off that node

 function handleClick(xPos, yPos) {
     var column = Math.floor(xPos / gameCanvas.blockSize);
     var row = Math.floor(yPos / gameCanvas.blockSize);
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return;
     if (board[index(column, row)] == null)
         return;
     //If it's a valid block, remove it and all connected (does nothing if it's not connected)
     floodFill(column, row, -1);
     if (fillFound <= 0)
         return;
     gameCanvas.score += (fillFound - 1) * (fillFound - 1);
     shuffleDown();
     victoryCheck();
 }

 function floodFill(column, row, type) {
     if (board[index(column, row)] == null)
         return;
     var first = false;
     if (type == -1) {
         first = true;
         type = board[index(column, row)].type;

         //Flood fill initialization
         fillFound = 0;
         floodBoard = new Array(maxIndex);
     }
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return;
     if (floodBoard[index(column, row)] == 1 || (!first && type != board[index(column, row)].type))
         return;
     floodBoard[index(column, row)] = 1;
     floodFill(column + 1, row, type);
     floodFill(column - 1, row, type);
     floodFill(column, row + 1, type);
     floodFill(column, row - 1, type);
     if (first == true && fillFound == 0)
         return;     //Can't remove single blocks
     board[index(column, row)].dying = true;
     board[index(column, row)] = null;
     fillFound += 1;
 }

 function shuffleDown() {
     //Fall down
     for (var column = 0; column < maxColumn; column++) {
         var fallDist = 0;
         for (var row = maxRow - 1; row >= 0; row--) {
             if (board[index(column, row)] == null) {
                 fallDist += 1;
             } else {
                 if (fallDist > 0) {
                     var obj = board[index(column, row)];
                     obj.y = (row + fallDist) * gameCanvas.blockSize;
                     board[index(column, row + fallDist)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
     //Fall to the left
     fallDist = 0;
     for (column = 0; column < maxColumn; column++) {
         if (board[index(column, maxRow - 1)] == null) {
             fallDist += 1;
         } else {
             if (fallDist > 0) {
                 for (row = 0; row < maxRow; row++) {
                     obj = board[index(column, row)];
                     if (obj == null)
                         continue;
                     obj.x = (column - fallDist) * gameCanvas.blockSize;
                     board[index(column - fallDist, row)] = obj;
                     board[index(column, row)] = null;
                 }
             }
         }
     }
 }

 function victoryCheck() {
     //Award bonus points if no blocks left
     var deservesBonus = true;
     for (var column = maxColumn - 1; column >= 0; column--)
         if (board[index(column, maxRow - 1)] != null)
         deservesBonus = false;
     if (deservesBonus)
         gameCanvas.score += 500;

     //Check whether game has finished
     if (deservesBonus || !(floodMoveCheck(0, maxRow - 1, -1))) {
         gameDuration = new Date() - gameDuration;
         nameInputDialog.showWithInput("You won! Please enter your name: ");
     }
 }

 //only floods up and right, to see if it can find adjacent same-typed blocks
 function floodMoveCheck(column, row, type) {
     if (column >= maxColumn || column < 0 || row >= maxRow || row < 0)
         return false;
     if (board[index(column, row)] == null)
         return false;
     var myType = board[index(column, row)].type;
     if (type == myType)
         return true;
     return floodMoveCheck(column + 1, row, myType) || floodMoveCheck(column, row - 1, board[index(column, row)].type);
 }

 function saveHighScore(name) {
     if (scoresURL != "")
         sendHighScore(name);

     var db = openDatabaseSync("SameGameScores", "1.0", "Local SameGame High Scores", 100);
     var dataStr = "INSERT INTO Scores VALUES(?, ?, ?, ?)";
     var data = [name, gameCanvas.score, maxColumn + "x" + maxRow, Math.floor(gameDuration / 1000)];
     db.transaction(function(tx) {
         tx.executeSql('CREATE TABLE IF NOT EXISTS Scores(name TEXT, score NUMBER, gridSize TEXT, time NUMBER)');
         tx.executeSql(dataStr, data);

         var rs = tx.executeSql('SELECT * FROM Scores WHERE gridSize = "12x17" ORDER BY score desc LIMIT 10');
         var r = "\nHIGH SCORES for a standard sized grid\n\n"
         for (var i = 0; i < rs.rows.length; i++) {
             r += (i + 1) + ". " + rs.rows.item(i).name + ' got ' + rs.rows.item(i).score + ' points in ' + rs.rows.item(i).time + ' seconds.\n';
         }
         dialog.show(r);
     });
 }

 function sendHighScore(name) {
     var postman = new XMLHttpRequest()
         var postData = "name=" + name + "&score=" + gameCanvas.score + "&gridSize=" + maxColumn + "x" + maxRow + "&time=" + Math.floor(gameDuration / 1000);
     postman.open("POST", scoresURL, true);
     postman.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
     postman.onreadystatechange = function() {
         if (postman.readyState == postman.DONE) {
             dialog.show("Your score has been uploaded.");
         }
     }
     postman.send(postData);
 }