Use the PackageManager command and search for “hair” to install the “Woolly Rhino” plugin. This free plugin will run in Rhino 8 as well as the Rhino 9 Beta on Mac and Windows.
Hello @BrianJ , thanks for this nice plugin 
- for some simple mesh (2 triangles), perhaps the position could be a bit improved
- The base is sometimes highly twisted
- Adding some UV coordinates, basically just along the length could help adding material, other gradient …
You’re welcome @laurent_delrieu! Thanks for trying it out 
- The coverage is by area not poly count so you should be able to increase (or decrease) the density there to get a more even result with less clumping.
- That’s from the Curl setting, if you make it 0 you shouldn’t get that twist but I imagine there are some cases where it’ll happen due to gravity, wind etc. in combination with the other settings.
- Good idea and it’s actually where I started when it came to adding color. The need for UVs greatly complicated the workflow and I felt like it added too much friction. I opted for exposing a hidden vertex color shader instead to make it super easy to change the hair color or even combine groups of hair with different colors. The hair mesh is like any other disjoint mesh so if you assign say a planar map and a new material with a texture in it, that can replace the vertex color shader and give you some pretty cool effects…
is it possible to get a preview of the values changed?
Good idea! I’ve added it to the list
Also double click on the hair mesh brings up the command again to change values
I think it’s similar to fillets after the command is done the user can double click to edit it again
That one might be tough! Adding to the list to check how history could be used. Thanks.
Can this output equivalent curves only, rather than meshes?
Cheers!
I think preview might be enough then
Here’s a GH file that will make polylines from a hair mesh. It doesn’t grab the single tip point on each hair strand but otherwise might get you what you’re after.
Hair_to_Polyline.gh (6.2 KB)
This is such a great plugin. Definitely one of those that I would think should become a proper integration.
This works great. My suggestions:
- Primary output could be curves that can then be transformed into fur/grass as an option…
- Because you may be able to then have Spine, which will then transform this plugin to a generalised Hair & Grass modifier for Rhino. Spine would be a pipe method from base to tip.
- Having curve (& spine) output permits generality for other rendering integration.
I think this has an excellent number of uses as a generalised plugin; especially as it can work so well with things like Rhino Nature.
With generalised curve output as a baseline, you can then apply other effects like curve piping or even pull to other geometry for nicely randomised patterns.
I just pushed v1.2 to the PackageManager with an added crv output option (user beware! They are grouped but it’s not as speedy or efficient as the disjoint mesh method). I also added a preview for wrHair which was a great idea
While I was at it… wrFill is now much smarter.
Thanks for the feedback and Enjoy!
Hi @BrianJ
Great plugin - thank you! Would it be possible to add a percentage for WRShave, so that it doesn’t fully shave, but “thin out”, if you need areas a little less dense than others? TIA
-Jakob
Yes, I bet that could happen… adding it to the list. Thanks for the feedback!