This is by default. We can still enable the thicker outlines for high dpi
screens or personnal preference but it's not used atm. This also improve
the performance removing 1/3 of the outline cost.
This changes quite a few things.
- Outline is now per object.
- No more outline at object intersection (fix hairs problem).
- Simplify the code quite a bit.
We use a R16UI buffer to save one id per object outline. We convert this id
to color when detecting the outline.
Added textureGatherOffsets to the code but could not test on current hardware
so leaving it commented for now.
Group texture fetches to hide latency. 3.2ms -> 2.2ms (constant time improvement, not depending on scene complexity)
Could optimize further with textureGather (require OpenGL 4.0).
