Testing how external hierarchies could be loaded via own handlers.

See #2534

See #1985

Just set "sprite.fog = true" to get scene fog working on the sprite.

Internally, implementation is a bit different than for other objects: because there is just a single material for all Sprites, fog is always compiled into the shader and it's turned on/off (or fog type is changed) via uniform.

This is going to be tricky for models loaded as full scenes like Collada or OBJ (though there first we will need to figure out how to handle these at all in scene format / SceneLoader).

Not tested yet, but it should work in the same way like vertex colors in Ribbons: add one Vector3 with normal per vertex to "geometry.normals" array.

It's then up to the application layer to fill in proper values. It's use case specific how normals for triangle strips would get computed - for simple ribbon meshes it could be very similar like smooth normal computation for regular Mesh objects.

If degenerate triangles are used for pseudo-connected single ribbon mesh planes, application would need to take into account vertex adjacency.

The same like for lights, cameras now live in general "objects" section.

Lights now live in "objects" section together with meshes instead of its own "lights" section.

TODO: cameras should also follow this pattern.

This make Firefox behave consistently with Chrome - on clicking export buttons content is opened in a new tab instead of triggering "save" modal dialog.

See discussion: https://github.com/mrdoob/three.js/commit/dc71940a851caa4abf5176421d413d46f1abf3f5

Added XHR 'withCredentials' option to JSONLoader to send cookies with cross-site requests (e.g. json model access token)

Cleaned up custom stats.js styling in examples (thanks to @mrdoob for showing me this is possible ;).

Experimenting with "geometry.buffersNeedUpdate".

For the moment just with material parameters which are exposed via UI.