Using boolean vector instead of "if ( expression && expression )".

This helps for hard shadows code path. There are still some problems with soft shadows code path, which still don't want to compile.

With a little twist - per color component mixing of regular and wrap-around lightings.

Work in progress. Still just experimenting. Probably will make some auto-adding of plugins.

https://github.com/mrdoob/three.js/pull/689

New per-pixel Phong code is enabled by setting `perPixel` parameter in Phong material.

This version is able to light single untesselated quad correctly.

Also it doesn't have point lights number limitation caused by varyings, all lights pass just through uniforms.

Performance wise it seems surprisingly quite similar to old version (stress test is ~6 fps faster with new version, though I guess for different use cases / GPUs it can differ).

Metal makes specular term multiplicative (default is additive). This is to be able to have textured materials that do not have diffuse color, just a specular one, to get metallic look (additive specular gives plastic look).

Removed diffuse color influence on ambient term in Phong. This was causing texture disappearance when diffuse color was black.

Made Lambert more similar to Phong: now it also has ambient color parameter. Before ambient light was affecting Lambert as if ambient color was always 0xffffff.

Added morph to rendering testbed.
Simplified shadowmap shader snippet gamma handling.

Do not merge, this is very experimental, not sure about correctness, also tons of unsolved things.

Before lighting was messed up in dynamically generated cube maps.

Dynamic cube maps need to have flip uniforms (flipEnvMap / tFlip) set to 1, static cube maps to -1 (default).

For standard materials this is handled automatically, it's just something to be aware of when using cube maps in custom ShaderMaterials (dynamic and static cube maps have different cube face orientations, dynamic ones are correct, static ones need flipped x-axis in lookup vector).

There is still mystery of disappearing last cube face (negative-Z) and weirdly clipped objects in cars demo (works ok in simpler test).

This feels more intuitive, otherwise ambiently lit textured surfaces look weird.

Turns out I had it right before after all: to get rid of artefacts it should be multiplied by diffuse term (instead of being patched by conditional).

Hopefully this fixes several problems:

- ambient component not modulated by scene ambient light
- specular component not getting light colors
- unnecessary opacity use in lighting calculations
- unnecessary vertex shader light computation for Phong
- unnecessary use of one varying in Phong

Also removed unused material Sprite parameter.

Added alphaTest parameter to base Material plus corresponding shader chunk in standard materials implementation.

This is for having on/off transparency without sorting using threshold value in alpha channel of diffuse texture.

By default it's switched off (alphaTest = 0).

AlphaTest is not yet handled in shadow maps. This would require passing of diffuse texture to depth material in shadow map render step (and more permutations of depth material).

Doesn't seem to produce visible difference.

Nine tap sampling, by default it's on, switch off with:

renderer.shadowMapSoft = false;

Added Matrix4 type to uniforms. Fixed Texture cloning. Fixed uniforms cloning for Vector2, Vector4 and arrays.

Thanks to @fazeaction for spotting this.

Testing out texImage2D instead of texSubImage2D again.
@alteredq: which browsers/os didn't like this combo?

Blender normal map support is work-in-progress:
 - for individual models normal map shader will need to be refactored to use standard scene lights
 - would be nice to handle also bump maps (a lot of Blender assets do not use "use_normal_map" flag on tangent space normal texture but instead use "use_map_normal" flag on texture slot of grayscale heightmap texture)

Also some whitespace cleanup.