Here my new Extension for Unity 5.4!
Hair designer is an amazing tool for generating dynamic hair and fur within unity editor.
You can paint and edit hair strands within unity.
The hair shader animate each strand 
It’s very very fast!
Available on the Asset Store
Version BASIC & PRO
( source code included in Pro version )
here a timelapse
Very cool. looking forward to it.
Can this do coarse afro hair?
Looks good, but I wonder about limitations and work arounds. For example, how to handle parted hair, long strands that are combed back, bangs, whorl, braids / pony tail, collisions, hats, etc.
I would also advise to have:
Totally rad 
What are the tri counts of those hair meshes?
You can create semi-long hair, I’ll add pony tail and long hair later.
The system is designed with layers, so you can create different hair (ex : with or without hat) and switch between them.
I will add different kind of layers : paint mesh, ponytails, procedural generator…
I’ll also add a collision system
The shaders are compatible with shader model 2, so it should work on all platforms
This is the first release, the system is ready for next steps.
I didn’t try to optimize 
3672 tri
Yes I could do a system to generate procedural hair strand, I’ll think about it.
There’s a layer system, so you can work on different parts independently.
I can’t bake data into textures, there’s a lot of parameters for each strand, but I think I’ll do some procedural generators.
Hair mesh is deformed by bones in the same way than the original mesh
You can easily paint dynamic fur!
Does the hair inherit the bone-weight averages of the triangles they are attached to? For systems that morph using bones (like UMA)?
It’s attached to the nearest vertex, maybe I could add different mode for getting bone weights
thank you for the inspiration
The package include a compatible version of the standard shader, so you can use PBR materials.
Here some feathers 
Can make it so normal of the mesh are automatically aligned with the scalp? For example let’s assume you have a hair straight up on the sclap, normally being a plane the normal would be tangential to the sclap, instead the normal should be in the same direction of the plane, which would simulate the effect of the volume of hair, this is used to get tree have nice shading with their leafy planes.
Each hair strand is designed with a curve, I could set the vertices’ normals to the tangent of the curve.
Thank you for this feedback, I’ll try to add a lerp factor for switching the normal.
Edit : I’ve added a ‘Normal Switch’ parameter, the result is really great, a better control of the reflections on the hair cut
Playing with the tool for generating grass
I can change the density in real time
