===================================================================
--- original.js
+++ change.js
@@ -2,31 +2,101 @@
 	var self = Container.call(this);
 	parent.addChild(self);
 	self.x = x;
 	self.y = y;
-	self.width = args.width;
-	self.height = args.height;
+	var landscapeTiles = args.landscapeTiles;
+	var lookup = args.lookup;
+	var xIndex = args.xIndex;
+	var yIndex = args.yIndex;
+	var width = args.width;
+	var height = args.height;
+	var density = args.density;
+	var key = args.key;
+	self.checkCollision = checkCollision;
+	self.activate = activate;
+	self.width = width;
+	self.height = height;
+	self.active = false;
+	self.key = key;
 	var obstructions = [];
-	var densityChance = Math.pow(1 + args.density, 3) / 100;
-	var obstructionTypes = ['largeTree', 'smallTree', 'deadTree', 'rock', 'stump'];
-	var spawnBorder = 10;
-	var cellSize = 100;
-	var cols = Math.ceil(args.width / cellSize);
-	var rows = Math.ceil(args.height / cellSize);
-	var cellWidth = args.width / cols;
-	var cellHeight = args.height / rows;
-	var cellInnerWidth = Math.max(0, cellWidth - 2 * spawnBorder);
-	var cellInnerHeight = Math.max(0, cellHeight - 2 * spawnBorder);
-	for (i = 0; i < cols; i++) {
-		for (j = 0; j < rows; j++) {
-			if (Math.random() <= densityChance) {
-				var obsX = cellWidth * i + spawnBorder + Math.random() * cellInnerWidth;
-				var obsY = cellHeight * j + spawnBorder + Math.random() * cellInnerHeight;
-				var type = obstructionTypes[Math.floor(Math.random() * obstructionTypes.length)];
-				obstructions.push(new Obstruction(self, obsX, obsY, type));
+	var visual = self.createAsset('hitbox', 'Landscape area', 0.5, 0.5);
+	visual.alpha = 0;
+	visual.width = width;
+	visual.height = height;
+	function checkCollision(player, x, y) {
+		var reach = 200;
+		var dx = Math.abs(x - self.x);
+		var dy = Math.abs(y - self.y);
+		if (dx < width / 2 + reach && dy < height / 2 + reach) {
+			for (var i = 0; i < obstructions.length; i++) {
+				if (player.hitbox.intersects(obstructions[i].hitbox)) {}
 			}
 		}
 	}
+	function activate() {
+		if (!self.active) {
+			self.active = true;
+			var densityChance = Math.pow(1 + density, 3) / 100;
+			var obstructionTypes = ['largeTree', 'smallTree', 'deadTree', 'rock', 'stump'];
+			var spawnBorder = 10;
+			var cellSize = 100;
+			var cols = Math.ceil(width / cellSize);
+			var rows = Math.ceil(height / cellSize);
+			var cellWidth = width / cols;
+			var cellHeight = height / rows;
+			var cellInnerWidth = Math.max(0, cellWidth - 2 * spawnBorder);
+			var cellInnerHeight = Math.max(0, cellHeight - 2 * spawnBorder);
+			for (i = 0; i < cols; i++) {
+				for (j = 0; j < rows; j++) {
+					if (Math.random() <= densityChance) {
+						var obsX = cellWidth * i + spawnBorder + Math.random() * cellInnerWidth - width / 2;
+						var obsY = cellHeight * j + spawnBorder + Math.random() * cellInnerHeight - height / 2;
+						var type = obstructionTypes[Math.floor(Math.random() * obstructionTypes.length)];
+						obstructions.push(new Obstruction(self, obsX, obsY, type));
+					}
+				}
+			}
+		}
+		var leftKey = xIndex - 1 + ':' + yIndex;
+		var rightKey = xIndex + 1 + ':' + yIndex;
+		var downKey = xIndex + ':' + (yIndex + 1);
+		if (!lookup[leftKey]) {
+			landscapeTiles.push(lookup[leftKey] = new LandscapeTile(parent, self.x - width, self.y, {
+				key: leftKey,
+				density: Math.random(),
+				xIndex: xIndex - 1,
+				yIndex,
+				landscapeTiles,
+				width,
+				height,
+				lookup
+			}));
+		}
+		if (!lookup[rightKey]) {
+			landscapeTiles.push(lookup[rightKey] = new LandscapeTile(parent, self.x + width, self.y, {
+				key: rightKey,
+				density: Math.random(),
+				xIndex: xIndex + 1,
+				yIndex,
+				landscapeTiles,
+				width,
+				height,
+				lookup
+			}));
+		}
+		if (!lookup[downKey]) {
+			landscapeTiles.push(lookup[downKey] = new LandscapeTile(parent, self.x, self.y + height, {
+				key: downKey,
+				density: Math.random(),
+				yIndex: yIndex + 1,
+				xIndex,
+				landscapeTiles,
+				width,
+				height,
+				lookup
+			}));
+		}
+	}
 });
 var Obstruction = Container.expand(function (parent, x, y, type) {
 	var self = Container.call(this);
 	parent.addChild(self);
@@ -55,20 +125,18 @@
 var Game = Container.expand(function () {
 	var self = Container.call(this);
 	var stageWidth = 2048;
 	var stageHeight = 2732;
+	var tileSize = 512;
+	var tileMargin = tileSize / 2 + 100;
 	var background = self.createAsset('background', 'Fullscreen background', 0, 0);
+	var landscapeLookup = {};
 	var landscapeTiles = [];
-	var position = {
-		x: 0,
-		y: 0
-	};
 	var direction = {
 		x: 0,
 		y: 0
 	};
 	var speed = 0;
-	var totalDistanceY = 0;
 	background.width = stageWidth;
 	background.height = stageHeight;
 	var targetPosition = {
 		x: 0,
@@ -85,8 +153,18 @@
 	});
 	speedText.anchor.set(1, 0);
 	speedText.x = stageWidth;
 	speedText.y = 0;
+	landscapeTiles.push(landscapeLookup['0:0'] = new LandscapeTile(self, player.x, player.y, {
+		width: tileSize,
+		height: tileSize,
+		density: -1,
+		lookup: landscapeLookup,
+		xIndex: 0,
+		yIndex: 0,
+		key: '0:0',
+		landscapeTiles
+	}));
 	LK.gui.topRight.addChild(speedText);
 	var isMouseDown = false;
 	stage.on('down', function (obj) {
 		isMouseDown = true;
@@ -108,18 +186,21 @@
 		speed = Math.max(0, speed * 0.95 + acceleration);
 		player.platformGraphics.rotation = angle + Math.PI / 2;
 		var velocityX = Math.cos(angle) * speed;
 		var velocityY = Math.sin(angle) * speed;
-		for (var i = self.landscapeTiles.length - 1; i >= 0; i--) {
+		for (var i = landscapeTiles.length - 1; i >= 0; i--) {
 			var landscapeTile = landscapeTiles[i];
 			landscapeTile.x -= velocityX;
 			landscapeTile.y -= velocityY;
-			if (landscapeTile.y < -100) {
+			if (landscapeTile.y < -(tileSize / 2 + tileMargin)) {
 				landscapeTile.destroy();
 				landscapeTiles.splice(i, 1);
+				landscapeLookup[landscapeTile.key] = undefined;
+			} else if (landscapeTile.x > -tileMargin && landscapeTile.x < stageWidth + tileMargin && landscapeTile.y < stageHeight + tileMargin) {
+				landscapeTile.activate();
 			}
+			speedText.setText('Speed: ' + speed);
 		}
-		speedText.setText('Speed: ' + speed);
 	});
 	function angleClamp(angle) {
 		return angle >= 0 ? angle : angle < -Math.PI / 2 ? Math.PI : 0;
 	}