There shouldn't be any change in functionality, just moved code around and clarified comments.

2d texture encapsulates bitmap, wrapping and minifying/magnification parameters.

Which reminds me, maybe also minifying/magnification options should be parameters in Texture object.

Though as defaults are "best" (LINEAR / LINEAR_MIPMAP_LINEAR = trilinear filtering), this would make sense just for special use cases like when trying to achieve "retro" look (like in Minecraft, http://gregs-blog.com/2008/01/14/how-to-turn-off-bilinear-filtering-in-opengl/ ;).

Not sure about adding car models, they are quite big (even binary ones). To be removed if it makes troubles with git / GitHub.

Not anymore automatic, but also much less wasteful.

Has to be called in tandem with scene object removal:

    scene.removeObject( object );
    webglRenderer.removeObject( scene, object );

In WebGLRenderer transparent materials are now handled in the same pass as blended materials (resulting in better fake transparency ;)

The order of render passes is now following:

1. opaque materials with normal blending

2. opaque materials with additive blending
3. opaque materials with subtractive blending

4. transparent materials with additive blending
5. transparent materials with subtractive blending
6. transparent materials with normal blending

With growing number of passes it's possible it may be worth to do some pre-sorting, though it would have to be tested.

Current way is fairly cheap as if there are no corresponding materials in the pass, for loops just blast through (potentially many very cheap operations).

Pre-sorting would mean creating arrays on the fly in each frame (one expensive operation with effect on garbage collection, which especially Firefox is currently very bad at).

Wrapping options follow WebGL specs: ClampToEdge [default], Repeat, MirroredRepeat.

Made up MeshCubeMaterial (missing from alteredq branch)

Removed a loop at line projection time.

Added MeshCubeMaterial: WebGLRenderer specific material for more efficient rendering of panoramas when doing cube mapping.

Also moved loadImageArray utility function from examples into TextureCube.js

To be used like this:

    var urls = [ "px.jpg", "nx.jpg", "py.jpg", "ny.jpg", "pz.jpg", "nz.jpg" ];
    var images = THREE.loadImageArray( urls );
    var textureCube = new THREE.TextureCube( images );

    // create scene

    var objectMaterial = new THREE.MeshBasicMaterial( { color: 0xffffff, env_map: textureCube } )
    createScene( objectMaterial );

    // create panorama

    var size = 100000;
    var panoMaterial = new THREE.MeshCubeMaterial( { env_map: textureCube } );
    var mesh = new THREE.Mesh( new Cube( size, size, size, 1, 1, null, true ), panoMaterial );
    sceneCube.addObject( mesh );

Warning: this functionality is currently changing a lot, expect things to get broken before stabilization.

I can't see any other WebGL example being affected by this change (for bad).

Updated some examples.
CanvasRenderer: Skip render when opacity is 0.

Fix is a bit dirty, but at least it's short ;)

Added refractive mapping and mixing combination mode for the environment map and the underlying material.

This commit has handful of things going on:

- had to sacrifice one light to please ANGLE, making it again up to 4 instead of up to 5 total lights :(

- Basic / Lambert / Phong materials now have new parameters:

    "combine": THREE.Mix | THREE.Multiply [default]

      - tells how to combine environment map with the original material:

         - "Multiply" creates chrome-like metallic look (it's what was already there),
           color of the underlying material is multiplied with the environment map,
           this creates different colored metals

         - "Mix" creates shiny plastic look
            color of the underlying material is lerped with the environment map,
            amount of the contribution from the environment map is controlled
            by another new parameter "reflectivity"

    "reflectivity": <float> [from <0.0, 1.0>]

       - controls mixing of underlying material and environment map for "Mix" combine mode
          0: pure underlying material, zero contribution from environment map (Basic/Lambert/Phong)
          1: pure environment map, zero contribution from underlying material (uncolored chrome look)

    "refraction_ratio": <float>

      - controls refractive mapping, ratio of the index of refraction in the medium containing the incident ray
        to that of the medium being entered
      - sensible values seem to be from ~0.6 - 1.0
        (in theory, e.g. air/glass should be 0.75, but this looks weird, values between 0.9 - 1.0 give the most interesting results,
         though maybe there is bug somewhere in my code)

      - for use refraction mapping, just add parameter to TextureCube like this (default is reflection mapping)

          "new THREE.TextureCube( images, THREE.RefractionMap )"

CanvasRenderer code clean up

Cleaned up the escher cubemap code a bit. Also, I think it looks much nicer without illumination... ?
At first I though the cube around the sphere was x-inverted (unless the in tention is to simulate refraction...) I've tried changing that but the effect is still weird. I guess those textures work mainly for the sphere and not for the panorama.

I reused the code and did another example using the skymap. More to come ;)

I can see some lines at the edges of the planes though. I guess that's antialiasing kicking in. Should be fixed with a proper cube mesh I guess.

CanvasRenderer has a property called `autoClear` which is true by default. By making it false you have control of when the renderer cleans the screen (by calling renderer.clear()). I wonder if something like that can be added to the WebGLRenderer? That way we can render the cube outside the spheres from a diferent camera (centered in the middle of the screen) than the spheres floating.

Also, added `shading` parameter to `MeshBasicMaterial` (environment mapping was being rendered faceted when using `MeshBasicMaterial` because `shading` was missing (and thus Faceted)).

TODO:

  - maybe image array loader should go into TextureCube.js so that people could just reuse the code

  - it may be worth to be able to specify different combination of environment map and underlying material (in single render pass),
    currently color/color map/environment map are multiplied, though addition also produces very interesting looking materials

Cloned materials.html -> materials_gl.html to have easier test for WebGLRenderer.

TODO:

Investigate why this test is so slow. It shouldn't be, materials_shaders.html is more complex and yet it is much faster (36 vs 60 fps).

MeshFaceMaterial with every face different is pretty bad use case for WebGLRenderer, but this still doesn't fully explain slowdown :(.

Pushed REVISION to 29.

Render first objects / material groups that use normal blending, then render ones which use additive blending.

Proper solution should be: sort triangles by blending, render all the normal ones, sort additive ones by depth and then render them back to front.

http://www.opengl.org/resources/faq/technical/transparency.htm
http://nehe.gamedev.net/data/lessons/lesson.asp?lesson=08

While this is acceptable in C++ / OpenGL, with JavaScript / WebGL this would kill the performance (you would need to sort triangles in JS and also create new buffers every frame).

Also tried to come up with subtractive / darken blending, but didn't find any satisfactory formula :(.

This is actually tricky due to multimaterials and vertex normals.

The practical effects of "shading" parameter in WebGLRenderer are currently following:

- if your model has vertex normals, now you can "dumb down" its shading by specifying THREE.FlatShading for MeshLambertMaterial and MeshPhongMaterial
- if your model has only face normals, it will always have just flat shading, no matter which shading you set, no escape from this
- if your model has multiple materials, smooth shading always "wins", meaning if there is at least one smooth shaded material in multimaterial group, all other materials in this group will be also smooth shaded (this is solvable by having multiple normal buffers, but seems wasteful, at least for the moment, till there are no practical use cases)

Currently implemented shading / material combinations:

  - MeshNormalMaterial: FlatShading [default], GouradShading
  - MeshDepthMaterial:  no shading parameter in material, uses own specific shading
  - MeshBasicMaterial: no shading parameter in material, uses own specific shading
  - MeshLambertMaterial: FlatShading, GouraudShading [default]
  - MeshPhongMaterial: FlatShading, PhongShading [default]

Removed Loader.js from compiled lib
Fixed examples

CanvasRenderer/SVGRenderer: More code clean up and optimisations.