Setting Up Stylized Fur with Ornatrix, gFur & UE4

Introduction

Hello! My name is Glen Yancey and I’m the Lead Character Artist for Lightyears from Home. In this article, we’ll take a look at Monty, the player’s friend and sidekick who will help the player turn resources found throughout the world into specialized equipment and weapons. 

A major design element for him was to create a character resembling a "space palico" to help you along your journey! The fun and most challenging part of designing the characters was creating grooms for both of them.

Tools Used for Grooming

Sam (our main hero) was relatively easy, as there are many tutorials and resources online to help with designing human hairstyles in XGen. Monty, however, was much more of a challenge. XGen turned out to be too difficult and buggy to make his fur, so we ended up going with a combination of gFur and Ornatrix as our solution. gFur is a plugin anyone can get on Unreal Engine Marketplace and is a fins/shells-based shader. Anyone familiar with Conker’s Bad Fur Day, Ratchet and Clank, or Shadow of the Colossus will be familiar with this style of fur rendering.

Ornatrix is a far more high-end tool that can create some truly amazing hair and fur styles and has an intuitive export feature with Unreal support. I followed a series of tutorials from CharlyTutors, a grooming artist who specializes in using Ornatrix. He documents all of his work and has very thorough guides on how to create various hairstyles and fur grooms for all types of characters.

The Workflow

The very first step starts by selecting a growth mesh and creating a Furball groom on top of it. This will generate a bunch of guides all over the growth mesh with fur interpolated between them sticking straight out. To tone things down a bit, the next step is to adjust the length of the fur guides.

There are many features in Ornatrix that let you tweak how the fur will be displayed. Right now I have the length reduced to resemble something close to short fur. 

The next step is to give the fur some basic direction. And Ornatrix has a very useful tool called Surface Comb which you can add to your modifier stack above the hairFromGuides modifier.

After applying the surface comb it’s as simple as just clicking on the Edit Sinks tool and then clicking and dragging on your growth mesh to start shaping the direction of your groom.

The next step is to create a distribution mask. You’ll want to mask out areas where you don’t want the fur to be generated. Eyes, mouth, nose, etc. To create a mask, select your hairFromGuides modifier and click the paintbrush icon next to the Distribution Multiplier slider. 

This will open up a menu where you can select the resolution of your mask, its starting fill color as well as the path where it will be stored. Your mesh needs to have UVs for this to work.

You’ll now be able to mask out areas by painting either black or white on the mesh to remove or add fur generation. I chose to set the paintbrush to Constant so the distribution of the fur is set to either 0 or 1. There are options for symmetry as well so painting the mask can be done quite quickly. When finished, deselect the tool and the next step involves adding clump modifiers. This is where the groom really starts to take shape.

Adding a clump modifier will place a set amount of clumps all over the mesh. There are setting you can tweak to adjust the amount or clumping at the roots and tips, as well as a distribution multiplier that you can create a mask to remove clumps where they aren’t needed.

To more precisely tweak the clumps, select your clump editing tool and draw a selection around various areas of the mesh you want to adjust. Once you have a selection you can delete the clumps, adjust the clump amount, and then re-add them to the selection.

This will allow you to have finer clumps in some areas of the groom, while also having chunkier clumps in other areas. This only scratches the surface of how complex the clumping modifier can get so I recommend checking out Ephere’s YouTube channel as well as CharlyTutors for more specific walkthroughs to find the solution that works best for you.

The next step involves adding more clump modifiers and a noise modifier to give the groom a lot more realism and life to it. I usually only use 2 or 3 clump modifiers. At this point, it’s also a good idea to ramp up the viewport hair strand count to 50-80% so you have a better idea of how your final groom will look.

The final step involves the more manual and artistic tools, comb, grab, and length.

These grooming tools let you shape the hair guides manually by brushing them in the direction you want. The tools themselves are pretty self-explanatory with the comb and grab brushes moving the hair in the direction of your strokes and the length brush adding or subtracting fur-guide length based on the direction of your stroke.

With just these few simple steps you can create a very competent-looking groom in just a few hours! 

For Monty specifically, I ended up creating 4 different grooms: A long fur section that is used for his cheeks and nape, a short fur section that covers most of his face and ears, an ear tuft section, and a whisker section. With all these grooms combined, we get a very fluffy boy!

To export these grooms to Unreal you just select the top furBallShape object in the Ornatrix modifier list and then File>Export Selection. Choose Ornatrix Alembic as your export file type and make use of the Unreal option.

Once in Unreal Engine, you can import your alembic files into your project and add the groom components to your skeletal mesh of choice and bind your alembics to the mesh. While in Unreal you still have options to adjust the groom so that it looks exactly as you want.

The screenshot below is how Monty looks in UE4:

Glen Yancey, Lead Character Artist

Interview conducted by Arti Burton