While this seems to be useless for Blender itself, it becomes more useful
for inter-application interoperability using Alewmbic, which doesn't have
simple way of storing and restoring hair system as Blender's hair system.
Even more, default IO type for hair is curves for Alembic as far as i can
see, so this change allows following:
- Being able to render hair system currently exported from Blender as a proper hair system.
- Being able to render hair saved from an external applications.
There are following limitations:
- No vertex color or UV coordinates are synchronized to such hair.
- NURBS are not fully supported -- they are only exporting CV without midpoints which is enough for Alembic.
This is simple to solve, but lets first have a bigger picture discussion about whether this patch is a complete rubbish or not.
The option is found below Cycles panel settings of Curve objects.