To have lighting consistent with shadows when using target.

Before SpotLight was a weird mix of shadow casted from PointLight and light casted from DirectionalLight.

After shadow mapping fixes orthographic shadow projection finally started to work.

Work in progress. Still need to figure out some way to set up shadow camera automagically with respect to the actual camera (so that whole scene is shadowed when the camera moves). For the moment shadow camera needs to be handled manually (like for SpotLight).

As per discussion here: https://github.com/alteredq/three.js/commit/835b57addaf328412b61a2b644ff5efd7fe6d25e

Thanks GUI-DAT ;)

Sidenote: these extra verbose Closure warnings are starting to pay off - I keep catching subtle bugs (like missing dependencies in rarely used code corners).

This allows to have different shadow map parameters for different lights, also it's easier to access parameters for tweaking / debugging.

Changes:

renderer.shadowMapWidth    => spotLight.shadowMapWidth
renderer.shadowMapHeight   => spotLight.shadowMapHeight

renderer.shadowMapBias     => spotLight.shadowBias
renderer.shadowMapDarkness => spotLight.shadowDarkness

renderer.shadowCameraNear  => spotLight.shadowCameraNear
renderer.shadowCameraFar   => spotLight.shadowCameraFar
renderer.shadowCameraFov   => spotLight.shadowCameraFov

Also added new uniform type "v2v" for array of Vector2 (to support per-light sizes of shadow maps).

This is for seeing how camera actually looks (frustum, line-of-sight, up), it's not a camera. Not sure about the name.

Shadows should be now done more correctly and also be a bit less fussy. Before RGBA encoded depth maps were getting messed up with blending (that's why everything was extremely sensitive to frustum size).

All examples with shadows had to be re-tweaked (shadows now behave differently).

Plus added "onUpdate" callback handling also for cube textures.

This is necessary for OpenGL where pow(0,0) is undefined and apparently can be negative, leading to negative specular light (in DirectX you just get zero).

Also refactored a bit regular Phong shader and refreshed Lee-Perry normal map example to be less zombie-like.

Updated Closure compiler. Added more verbose compile warnings. Fixed all compile warnings. Started to fix runtime warnings in examples.

For verbose compile warnings to be practical I had to add externs and disable some warnings manually (there were tons of complains about "global this" and "cannot instantiate non-constructor"). Other solution would be to annotate explicitly constructors all over the code base.

(prompted by John Carmack's praise of static code analysis http://altdevblogaday.com/2011/12/24/static-code-analysis/)

ATI OpenGL shader compiler doesn't seem to like texture access with UV coordinates generated in a loop.

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.

This exists also in Blender, useful for when you want to add shadows independent of lighting (it's cheaper to turn off SpotLight than to have it with 0 intensity).

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

As per @toji's "don't lie to WebGL about your format" recommendations in WebGL Camp 4 talk (http://media.tojicode.com/webglCamp4/#19).