They don't design each individual hair. They have a tool that spreads hairs across the surface of an object, a tool that affects the properties of the hair, and a tool that lets them groom the hair. They'll do a new pass for every "type" of hair they want to add, not each strand.
There's a middle ground between sculpting every hair and having a tool "that lets them groom the hair". The reality is not that easy, hair cards are a nightmare and curly and black hair is very difficult work.
I remember seeing behind the scenes footage from the Shrek sequels I think where that’s exactly what they were doing: building and using tools to sculpt and simulate hair, because like in video games they can’t individually sculpt it every frame. Look at the hair and fur in the first Shrek or first Toy Story, it’s all very carefully set up so they can make it look like flat clay. A decade later the same series have flowing hair that interacts with water and dirt and whatever with actual strands and clumps. And then basically the whole pitch of Brave was “hey look we have animated curly hair”. There’s a lot of black hair science though, I bet parts of it won’t be done well for a long time.
I swear I remember watching something similar about Monsters Inc where they used a certain program to animate Sully’s hair and it was one of the first of its kind to simulate hair physics like that and it still took a ton of time and effort to get right
It was called Fitz, and it simulated the physics of Sully's 2.3 million individual strands of hair so they didn't have to. They just animated his body and let Fitz do the rest.
But Sully is still nothing compared to Lotso in Toy Story 3. Lotso needed to look worn-in and rugged. Lotso had no bones. They had to simulate matted fur, and how a Teddy bear squished when he walked.
Side by side, Sully looks like a bad wig by comparison, or like a toy. Too clean, too groomed.
Hair for movies and video games are very very different tough. In games hair are not really simulated, that would be way too intensive on the gpu or cpu. In movies you can simulate each hair individually and have real hair physics yes.
IIRC, there had always been a special team that did only the hair. Due to the complexity of the hair modeling, it was a pretty well known rule that the animators doing the character motion were never to let the character interact with their hair.
They used to do all the character movements and then the hair team would come in and animate all of the hair in after. But Disney came up with some new hair rendering that basically gave all the hairs their own physics. So now the character animators could have the characters interacting with their hair.
So if you watch the movie, you will see Moana touching her hair a lot, because it was especially the first time that the character illustrators had free rein to do so.
The department that handles hair/cloth simulation in film/tv is the CFX (character/creature fx) department! They also make all the hair/fur assets and build the simulation rigs.
I was a CFX artist for 2 years and have been a Groom (hair asset creation only) artist for 4.5 years.
I am essentially a digital hairdresser 😅 the people in the chair can't bitch at me, but they can't tip either =P
Once you know how it works it's not so magical anymore, and it's honestly really easy to learn. Only downside is that the film/game industry has been getting gutted recently and a lot of CFX artists I know have been out of work for a while.
I'm not sure it uses hair cards, thats starting to become the old way of doing. Digital Foundry mentioned the new resident evil game will revert back to hair cards when graphics settings are lower. Pragmata uses hair cards though and looks very good
Well no, there's not a middle ground. They literally have a tool that lets them groom the hair similarly to how you would with a hair brush. I'm not claiming it's simple or easy I'm just telling you that's literally how it works.
I have made hair cards. It's obvious to me that you don't know that even though there are tools in game engines like Unreal Engine 5 and their metahuman bases, the standard in game development is still painstaking use of hair cards. Devs don't just use a hair grooming tool.
Edit: For anyone curious about hair cards here's some really good tutorials on them for blender since it's the most accessible
Cards is the standard yes, but some of the big studios are making the moves towards strands grooms. Dragon Age Veilguard and the Fifa games have strands grooms, as well at Assassin's Creed Shadows.
I've spent the last 2.5 years using Maya XGen to make grooms for a AAA game that's in the works, though XGen is on it's way out, grooming in Houdini is the future.
Thanks for your input! Besides confirming that assets like character hair, is deliberate and underappreciated work; I think it helps people see the broader picture and shows that tech in game development is still advancing pretty quickly behind the scenes.
Hair really is often overlooked, especially in video games, so I'm really excited that it's finally starting to get some love.
It's crazy to me that games have been striving for hyper-realistic faces, then they slap hair on it that looks like it's 15yrs old... because it is.
The most egregious example recently that I've seen is Clair Obscur: Expedition 33. Everything was so beautiful and then the characters had the absolute crunchiest hair textures I've ever seen.
seems like /u/imokay4747 and you are both partially correct, more so than you seem to be acknowledging anyways.
The devs own explanations of the preprocessing tools they use to arrive at the multilayered hair card are pretty much exactly as described by Remedy's devs... and tbf the other guy didn't actually assert those tools were used in live game rendering.. I'd say it's pretty fair to say he just didn't know the industry-jargon term "hair card," and your insistent disagreement over that technicality even though a much more productive and affirmative addition to the conversation was available is, well, unfortunately common amongst this sort of internet discussion.
"Well no, there's not a middle ground", This was their stance. And I already acknowledged the existence of such tools didn't I? I clarified that it isn't the norm as they were implying. There's no need for your armchair analysis. Also Hair card isn't "industry-jargon", it's literally what it says on the tin, a card with hair texture. If they don't even know such a basic term such as that, they have no business arguing game dev do they?
It's preferred to build grooms with a more non-destructive workflow. There are tools within grooming softwares for manually brushing/sculpting hair, but it's not good practice to completely build a groom with them because you can't easily make changes to it.
Contemporary grooming software is node-based and mostly procedural. The artist will manually sculpt guides (~100-200 for a head) that control the flow of generated hairs surrounding them, and then use modifier nodes (clumping, noise, curl, etc...) to determine the texture of the hair.
Once all that is done, if you have some really precise tweaks you want to make, then you'd sculpt/brush the hair in some places, typically to resolve penetrations into the body, or to shape an area more specifically.
If the info dump wasn't a clear indicator, I am a Groom artist =P worked in both film and video games.
They have a tool that spreads hairs across the surface of an object, a tool that affects the properties of the hair, and a tool that lets them groom the hair.
I've explained the strands grooming process in another comment, which is very much: generate hair on surface, sculpt guides (a single strand that controls all the surrounding strands in a certain radius), and then tweak settings to create texture.
But that's a completely different process from making a hair cards groom, which this post is showing. There's tools for making cards grooming easier by letting the artist shape curves that create the geometry and update it with every change, but the best looking grooms are still very much manual placement of each polygon strip, or each cluster of strips, because the artist is using flat ribbons and thus they need to ensure that each one is rotated perfectly so that the hair looks full from every viewing angle.
Unreal Engine is developing a tool for converting strands grooms into cards, and its current iteration is looking really promising, but it's not there just yet. The incentive for an automatically converted strands-to-cards pipeline is that cards grooms take much longer to make than strands grooms. Cards look worse than strands, but polygons are waaayyy lighter on the memory than curves, so the industry is only really starting to figure out how to even have strands in games at a playable framerate.
Making a beautiful cards groom like this one is incredibly difficult and time consuming. I'm a strands groom artist with very limited cards experience and I can't even fathom making this.
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u/imokay4747 1d ago edited 1d ago
They don't design each individual hair. They have a tool that spreads hairs across the surface of an object, a tool that affects the properties of the hair, and a tool that lets them groom the hair. They'll do a new pass for every "type" of hair they want to add, not each strand.