Revert to pre-atlas voxel-texture. Fixes voxel/voxelmetaverse#14

voxel-texture 0.5.0 switched to use texture atlases, packing all the block
textures into one graphic for efficiency purposes. However, this introduces
two problems:

- With the culled mesher (default as of voxel-engine 0.17+), I get serious lag
spikes (30-60 ms frames, or unplayably higher) when placing/breaking blocks, and also slow
page load as the meshes are built (see voxel/voxelmetaverse#10)

- With the greedy mesher, performance is much better (fixes first issue) but textures are stretched
across each of the greedily constructed meshes, instead of tiled across each block (see voxel/voxelmetaverse#14)
Example: https://f.cloud.github.com/assets/5897956/1651233/1f478c9e-5aca-11e3-82cc-4028f1e1b1da.png

There are techniques for texturing greedy meshes, detailed in this article:

http://0fps.wordpress.com/2013/07/09/texture-atlases-wrapping-and-mip-mapping/

- Using array textures is ideal, but they won't be supported until WebGL 2.0 at earliest
https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7

- Otherwise, they can be tiled manually, but this requires a few tricks, would certainly
be worthwhile to implement, but is fairly complex. Maybe later, once I understand it better.

So for now, (unfortunately) I've reverted back to voxel-texture without atlases. This keeps
mesh recalculation fast (when breaking/placing blocks) and avoids stretched textures but
may slow down complex scenes with many materials (see performance improvement @shama noted in max-mapper#69).

README.md

@@ -242,11 +242,17 @@ For example, here we have 4 faces colliding with the bottom of our object:
 
 ### Textures
 
-Loading textures onto the texture atlas.
+Loading textures creates multiple "materials".
 
-```game.materials.load(['obsidian', 'dirt'], function(textures) { })```
+```var materials = game.materials.load(['obsidian', 'dirt'])```
 
-Both of these textures will be loaded into the texture atlas and expanded creating 2 voxel block types.
+Both of these textures come with 6 materials, one for each side of a cube, giving a total of 12 materials. By default, faces 1 to 6 are assigned materials 1 to 6. You can assign materials to faces in however you want. For example, we could load materials 7 to 12 (e.g. the dirt materials) like so:
+
+```js
+mesh.geometry.faces.forEach(function (face, index) {
+  face.materialIndex = index + 6 // obsidian texture indices 0 - 5, dirt 6 - 11
+})
+```
 
 ### Texture-less worlds with flat colors
 

index.js

@@ -53,7 +53,7 @@ function Game(opts) {
 
   this.playerHeight = opts.playerHeight || 1.62
   this.meshType = opts.meshType || 'surfaceMesh'
-  this.mesher = opts.mesher || voxel.meshers.culled
+  this.mesher = opts.mesher || voxel.meshers.greedy
   this.materialType = opts.materialType || THREE.MeshLambertMaterial
   this.materialParams = opts.materialParams || {}
   this.items = []
@@ -92,6 +92,7 @@ function Game(opts) {
   if (process.browser) {
     this.materials = texture({
       game: this,
+      THREE: THREE,
       texturePath: opts.texturePath || './textures/',
       materialType: opts.materialType || THREE.MeshLambertMaterial,
       materialParams: opts.materialParams || {},
@@ -226,14 +227,16 @@ Game.prototype.canCreateBlock = function(pos) {
 }
 
 Game.prototype.createBlock = function(pos, val) {
-  if (typeof val === 'string') val = this.materials.find(val)
+  if (typeof val === 'string') val = this.materials.findIndex(val)
+  if (pos.chunkMatrix) return this.chunkGroups.createBlock(pos, val)
   if (!this.canCreateBlock(pos)) return false
   this.setBlock(pos, val)
   return true
 }
 
 Game.prototype.setBlock = function(pos, val) {
-  if (typeof val === 'string') val = this.materials.find(val)
+  if (typeof val === 'string') val = this.materials.findIndex(val)
+  if (pos.chunkMatrix) return this.chunkGroups.setBlock(pos, val)
   var old = this.voxels.voxelAtPosition(pos, val)
   var c = this.voxels.chunkAtPosition(pos)
   var chunk = this.voxels.chunks[c.join('|')]
@@ -546,8 +549,8 @@ Game.prototype.showChunk = function(chunk) {
   this.voxels.meshes[chunkIndex] = mesh
   if (this.isClient) {
     if (this.meshType === 'wireMesh') mesh.createWireMesh()
-    else mesh.createSurfaceMesh(this.materials.material)
-    this.materials.paint(mesh)
+    else mesh.createSurfaceMesh(new THREE.MeshFaceMaterial(this.materials.get()))
+    this.materials.paint(mesh.geometry)
   }
   mesh.setPosition(bounds[0][0], bounds[0][1], bounds[0][2])
   mesh.addToScene(this.scene)

package.json

@@ -12,7 +12,7 @@
     "voxel-view": "git://github.com/deathcap/voxel-view.git",
     "voxel-raycast": "0.2.1",
     "voxel-control": "git://github.com/deathcap/voxel-control.git",
-    "voxel-texture": "0.5.6",
+    "voxel-texture": "0.4.0",
     "voxel-physical": "0.0.10",
     "voxel-region-change": "0.1.0",
     "raf": "0.0.1",