diff --git a/package.json b/package.json
index 0bc06c3..ab6eea8 100644
--- a/package.json
+++ b/package.json
@@ -2,10 +2,9 @@
   "name": "tilegame",
   "version": "0.0.0",
   "description": "Tile game",
-  "main": "index.js",
   "scripts": {
     "test": "echo \"Error: no test specified\" && exit 1",
-    "serve": "node .",
+    "serve": "node serve.js",
     "build": "webpack -p",
     "watch": "webpack -w --mode=development"
   },
@@ -24,5 +23,8 @@
     "standard": "^12.0.1",
     "webpack": "^4.41.5",
     "webpack-command": "^0.4.2"
+  },
+  "optionalDependencies": {
+    "express": "^4.17.1"
   }
 }
diff --git a/serve.js b/serve.js
new file mode 100755
index 0000000..baa0317
--- /dev/null
+++ b/serve.js
@@ -0,0 +1,11 @@
+#!/usr/bin/env node
+const express = require('express')
+const path = require('path')
+const app = express()
+
+app.use('/assets', express.static(path.join(__dirname, 'assets')))
+app.use('/', express.static(path.join(__dirname, 'dist')))
+
+app.listen(3000, function () {
+  console.log('server listening on 0.0.0.0:3000')
+})
diff --git a/src/entity.js b/src/entity.js
index 0ddfb44..5a0261b 100644
--- a/src/entity.js
+++ b/src/entity.js
@@ -129,7 +129,6 @@ class ItemEntity extends PhysicsEntity {
       this.istr = this.name + ' ' + (this.count + ent.count)
       this._life = 0
       ent.dead = true
-      continue
     }
   }
 
diff --git a/src/heightmap.js b/src/heightmap.js
index 460d7d3..ef15169 100644
--- a/src/heightmap.js
+++ b/src/heightmap.js
@@ -49,11 +49,9 @@ class HeightMap {
   // octaves      - Number of noise layers
   // period       - Distance above which we start to see similarities. The higher, the longer "hills" will be on a terrain.
   // lacunarity   - Controls period change across octaves. 2 is usually a good value to address all detail levels.
-  constructor (offsetX, offsetY, size, seed, amplitude = 30, persistence = 0.5, octaves = 5, period = 80, lacunarity = 2) {
-    this.ix = offsetX
+  constructor (offsetY, seed, amplitude = 30, persistence = 0.5, octaves = 5, period = 80, lacunarity = 2) {
     this.iy = offsetY
     this.seed = seed
-    this.size = size
 
     this.noise = new PerlinNoise(seedrandom(seed))
 
@@ -65,7 +63,7 @@ class HeightMap {
   }
 
   getNoise (zx) {
-    let x = ((this.size * this.ix) + zx) / this.period
+    let x = zx / this.period
 
     let amp = 1.0
     let max = 1.0
diff --git a/src/index.js b/src/index.js
index ea1b352..ab904f2 100644
--- a/src/index.js
+++ b/src/index.js
@@ -16,9 +16,9 @@ let frameCount = 0
 let fps = 0
 
 let vp = new Viewport(0, 0)
-let p = new Player(800, 1200, 32, 64)
+let p = new Player(1000, 1000, 32, 64)
 
-let height = new HeightMap(0, 32, 16, 0)
+let height = new HeightMap(32, 0)
 
 const chunkSize = 32
 const tileSize = 16
@@ -74,7 +74,7 @@ function start () {
     world.chunks = []
   })
   Debug.addCheckbox(Debug, 'drawGrid', function (argument) {
-    world.chunks = []
+    world.redraw()
   })
   playing = true
   gameLoop()
diff --git a/src/player.js b/src/player.js
index c0bf012..8a034f2 100644
--- a/src/player.js
+++ b/src/player.js
@@ -8,9 +8,9 @@ class Player extends PhysicsEntity {
   constructor (x, y, w, h) {
     super(x, y, w, h)
 
-    this.speed = 8
-    this.gravity = 1
-    this.jumpPower = 20
+    this.speed = 4
+    this.gravity = 0.5
+    this.jumpPower = 10
 
     this.inv = new Inventory(9)
     this.itemPickUpDistance = 40
diff --git a/src/tiles.js b/src/tiles.js
index 136e4da..86c658a 100644
--- a/src/tiles.js
+++ b/src/tiles.js
@@ -152,7 +152,7 @@ class TileLayer {
   }
 }
 
-class TilePhysicsLayer extends TileLayer {
+class TileCollisionLayer extends TileLayer {
   constructor (size = 16, tileSize = 16) {
     super(null, 'col', size, tileSize)
     this.empty = false
@@ -232,7 +232,7 @@ class Chunk {
     this.layers = []
     let bgLayer = new TileLayer(tileMap, 'bg', this.size, this.tile)
     let fgLayer = new TileLayer(tileMap, 'fg', this.size, this.tile)
-    let clLayer = new TilePhysicsLayer(this.size, this.tile)
+    let clLayer = new TileCollisionLayer(this.size, this.tile)
     for (let i = 0; i < this.size * this.size; i++) {
       let tileCoords = fgLayer.toXY(i)
       let tileAbs = this.toAbs(tileCoords)
@@ -402,6 +402,7 @@ class World {
   update (dt, vp) {
     this._active = []
     let posPoint = vp.chunkIn(this.chunkSize * this.tileSize)
+    // Load chunks if necessary
     for (let x = posPoint.x - 3; x < posPoint.x + 4; x++) {
       for (let y = posPoint.y - 2; y < posPoint.y + 3; y++) {
         if (x < 0 || y < 0 || x >= this.width || y >= this.height) continue
@@ -444,6 +445,7 @@ class World {
     }
   }
 
+  // Get a position in the world grid from an absolute position
   gridPosition (pos) {
     let a = this.chunkSize * this.tileSize
     let chunk = { x: Math.floor(pos.x / a), y: Math.floor(pos.y / a) }
@@ -454,6 +456,14 @@ class World {
     return { chunk: this.getChunk(chunk.x, chunk.y), tile }
   }
 
+  // Forces all loaded chunks to re-draw themselves
+  redraw () {
+    for (let i in this.chunks) {
+      this.chunks[i].dirty = true
+    }
+  }
+
+  // Draw all loaded in-view chunks and special layers
   draw (vp) {
     this._lastDrawCount = 0
     this._lastUpdateCount = 0
@@ -474,6 +484,7 @@ class World {
     }
   }
 
+  // Terrain collision test
   collide (obj) {
     if (!this._active.length) return null
     for (let i in this._active) {