GLSL cleanup & portability fix

Add comments to Firefox RGB format fix

SimulationRenderer: Fix COLOR_ATTACHMENT format bug in Firefox

That made phong_*vertex empty, so they have been removed.

Improved anaglyph encoding.

[: This' how the cool cats do it these days :]

ggx_smithcorrelated from frostbite 3.

OBJExporter: Fix Line Geometry Export

Box3: revert setFromObject()

Fix Errors in Tone Mapping Demo

Added support for standing space coordinates to VRControls

Presumably, the previous version was correct.

FIxes #8432.

OBJExporter: Use BufferGeometry instead of Geometry

Sprite: Fix raycast bug

Dev - trying shininess hack for #8381

Update from original

This commit changes OBJExporter so it handles BufferGeometry directly.

Raycasting with sprites is an approximation in that the sprite is treated as a disk. In addition, sprites can be non-square, and can be rotated.

With this change, if the sprite is square, the "clickable" region is inside the inscribed circle. If the sprite is non-square, the approximation is not very good, but it is better than before.