Houdini Grass Tutorial Using Grooming Hair and Fur Systems

In this video tutorial I go over how to create CGI Grass in Houdini using it's fur and hair grooming system. For Premium tutorials checkout / cginerd
Video Chapters
00:00 Intro
00:20 Beginning of Tutorial
00:50 Grouping
02:53 Selecting the Grass area
10:42 Adding fur
11:41 Grass Shader
13:27 Grass blade thickness
14:40 Grass length
15:45 Bending the grass
16:42 Setting grass direction
19:02 End of Tutorial & Outro
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Hi And welcome to CGI Nerd! My name is Alejandro Perez and here we go over tips and trick on how to improve your CGI Skills!!! I focus both on Video Game Development and Film Production.

[@desocrate]

Tutorial starts at 10mins, rest is him trying to prep his scene

[@Michaentus]

Very nice, clear and with a few tips for the terrain :)

[@ShaunFoster]

Great groom-able grass!

[@CGINerd]

Thanks Shaun :)

[@mgoldfarb]

Another method to remove the area of the sign is to create another group, this time using the Bounding Regions
the ground is the first input, the sign is the second (adding a transform after the sign so you can scale it up a bit or move it around helps)
change the Group Type to Points
change the Method to Keep in Bounding Region, Bounding Type to Bounding Object
this will make a group of all the points of the ground that are within the sign geometry
promote this new group to primitives
use group combine to make a new group that is the second group subtracted from the first
it's more nodes but it avoids the boolean, which can get tricky if lots of things change

[@filmanim5276]

Hi!
Thank you so much for your tutorial. Do you know how to randomize the thickness? I tried with an attribute and also a texture override, but nothing seems to work. Any idea? Many thanks.
Edited: I just updated to the latest version and it works now.

[@NinJA-mh4mc]

Awesome! It would be great if you could show how to simulate this with velum. :D

[@CGINerd]

That is a great idea! I will experiment a little.

[@alexwayland3463]

Hello! Thanks for this great tutorial!
I have one question
If I want some sphere falls into the grass, I make that sphere RBD Obj. and the gound - static object, but the sphere falls onto the tip of the grass like it is a ground... What should I do to make it fall into the ground and grass sneaks under it ?

[@njfx]

between the groom and the hairgen, drop two nodes : guide simulate and guide deform. Dig a bit into that. especially the Guide simulate and the vellum settings. In the collison tab, put your sphere in Collider SOP.

[@anarkijex]

would this be scaleable for archviz?

[@CGINerd]

Yes, I believe so. There are adjustments I would consider making depending on how close or far away the camera is to a particular area of grass on larger scenes. You can limit the number of segments on each of the blades of grass and the density of the grass in an area if it is further away from the camera.

[@xl000]

The bad UV on the stone boxes ruin the video.