diff --git a/tetris.js b/tetris.js
index a349109..b0d35f6 100644
--- a/tetris.js
+++ b/tetris.js
@@ -29,7 +29,7 @@ function TetrisGame(id, linesId) {
 	/**************/
 	this.gameIsOver = false;
 	this.linesCleared = 0;
-
+	
 	this.width = 10;
 	this.height = 15;
 	this.canvas = new TetrisCanvas(id, this.width, this.height, linesId);
@@ -55,6 +55,17 @@ function TetrisGame(id, linesId) {
 		this.drawCurrentBrick();
 	}
 	
+	this.xyToTileIndex = function(x,y) {
+		return y * this.width + x;
+	}
+	
+	this.tileIndexToXY = function(tileIndex) {
+		var y = Math.floor(tileIndex / this.width);
+		var x = tileIndex % y;
+		
+		return [x,y];
+	}
+	
 	this.getRandomBrick = function() {
 		return 1 + Math.floor(Math.random() * 7);
 	}
diff --git a/utils.js b/utils.js
index 01c8f5b..d8771b3 100644
--- a/utils.js
+++ b/utils.js
@@ -10,3 +10,13 @@ function createArray(length) {
 
     return a;
 }
+
+function arrayContains(array, element) {
+	for (var i = 0; i < array.length; i++) {
+		if (array[i] == element) {
+			return true;
+		}
+	}
+	
+	return false;
+}