Airborn: Creating Characters for a Stylized 3D Animation

Introduction

Steffen: Hey guys! My name is Steffen Unger and I am a 3D Character Artist and one of the founders of Airborn Studios, located in Berlin, Germany. I have been working in this industry for a good 20 years now and contributed to many games, including but not limited to Overwatch, Fortnite, Ori and the Blind Forest, and the Halo series.

Johannes: Hi, I am Johannes Figlhuber and I'm an Art Director at Airborn Studios. In the past, I was involved in games like Ori and the Blind Forest (Lead Artist), Spyro: Reignited Trilogy, and Crash Bandicoot 4 (Environment Concept Lead at Airborn). On the Airborn Showcase, I shared art direction duties with Simon Kopp and did concept work.

Tim: Hello, my name is Tim Moreels, and I'm a Lead 3D Character Artist at Airborn Studios! In the past six years, I've been working on many cool titles such as Overwatch and now Overwatch 2, Crash Bandicoot 4, Fortnite, and a handful more! And with the Airborn Showcase project, I've had the wonderful opportunity to work on the 3D model for the protagonist as well as setting up the character production alongside Steffen.

Victor: Bonjour! I am Victor Pancrazi, and I am a Character Artist at Airborn Studios. I've been working there for more than three years now. I also worked on projects such as Fortnite and Valorant. I was also responsible for the creature modeling on the Airborn Showcase, which was an awesome opportunity for me!

Airborn Showcase

Steffen: As already mentioned in the earlier article, the basic idea for the project has been floating around for more than 15 years now. It started as a little side project by me around the ending days of the first (and last) company I have been employed by.

Some of the biggest inspirations were Laputa – Castle in the Sky, Porco Rosso, and Studio Ghibli's movies in general. Other influences were movies like Steamboy and Tailspin, the Keepers of the Maser comic books, and games like The Legend of Zelda: The Windwaker and Crimson Skies. Over the years the project got more people hooked who contributed their art to various disciplines.

The project got quite a lot of attention at the time and even won awards. It also kickstarted many of our careers. It became the base for the founding of Airborn Studios as a game art production company and also made its way into many reference boards on way bigger productions than anticipated.

Fast forward a few years and we started wondering what if we spent some time with Airborn again, explored new places and characters, and used new technologies and a new engine to bring it to life. The result of these musings is what you see in the Airborn Showcase. A huge part of what we wanted to do with this project was to develop new workflows and learn new things which will come in handy (and by now already did) in later client productions.

Style Development

Johannes: We collected a bunch of references from various artists in a Miro board and went through the pros and cons of said pieces to define the general direction for the character art direction. Figuring out what Airborn is supposed to be and what it is not supposed to be.

Early ideation on the character style:

Concept development for the Mechanic character:

Early sculpt blockout by Tim Moreels:

Final 3D asset in Unreal Engine:

3D Execution

Tim: The basic 3D execution was mostly straightforward to us. This is our day-to-day business, this is what we know and can do. The biggest thing here probably was finding ways to stylize surfaces that are not in the vein of our usual stylized productions such as Overwatch, Fortnite, or Crash Bandicoot. We wanted to go into a more movie-like direction with thick cloth surfaces, smooth wrinkles, and chunky yet organic feeling shapes.

We didn’t record too many makings-of but we have a few showing our typical workflow from blockout in 3D modeling software to sculpting and detailing inside ZBrush.

Modeling inside 3ds Max, Blender, or Maya, depending on artists' preferences.

Sculpting inside ZBrush.

Steffen: Besides these points, the hair was certainly a big learning for us. We didn’t want to go for the usually used sculpted hair in stylized productions and thought about two routes to go. Going with haircards, which wasn’t completely unknown territory for us, or going after the groom to Unreal Engine's hair system route.

We just saw previews of a few productions we are working on and wanted to understand this better to be able to work in this field in the future. It will certainly come, but it's still some time until this is part of most productions. Mostly due to performance constraints, I would say. At the time when we started to work on the grooms, there was little to no documentation on how to do hair for Unreal. 

Thankfully there was a YouTube channel that showed a bunch of things in various tools and kept nagging Epic Games for more information on all fronts.

And from my personal perspective, I can recommend Michael Cauchi's Intro to XGen tutorial series, published by Flipped Normals.

We also dabbled around a fair bit with how to break up the silhouettes of the characters without creating too much manual labor. In the end, we came up with a solution that spawned particles on the mesh, grabbed its normals, roughness, base color, and other values, and applied those to the particles. 

In the end, we applied three different alphas for the cutout and used pixel depth offset to fade the particles into the body without super harsh transitions.

Final main characters inside Unreal Engine 5:

Texturing

On the texturing side of things, we experimented a lot with how we could stylize the surface finish of various materials. While we knew we would want a painterly appeal to the materials, we knew if we handpainted it all, the chances are that Roughness, Metalness, Ambient Occlusion, Diffuse Map, and so on will not align very well with each other. Despite its name, Substance 3D Painter is not really a great painting engine and the amount of work for the detail level we wanted was high. So we decided to figure out a way to do the groundwork quickly and reliably.

We wanted a few things we have control over:

• Brushstroke Size
• Brushstroke Length
• Brushstroke Flow
• Density of Brushstrokes

We tested various approaches in Substance 3D Designer and while some looked promising we never quite got to the point where we were happy with the output. We could create fine brushy looks with the tile sampler, but they wouldn’t really flow nicely, we had some solid starting points using other methods but it never quite worked out.

So we looked into how other games did it, and one of the most successful approaches we found was done by Street Fighter V. While we do not like their shading for looking too on the nose and very plasticky.

We wondered how they got the normals so nice and brushy while maintaining a nice and readable flow to the surfaces. Luckily they explained their approach in a GDC talk:

So, we played with the Snap Art 4 Filter, which instantly gave pleasing results. Had a really good take on following the flow of the model and was easy to use. The principle is very simple. Take the world space or object space normal map, run the filter over it, fix some seams and convert that into a tangent space normal map which will be used as an input inside Substance 3D Painter.

We created 3 different filter settings for broad, medium, and small brush strokes and applied those to the maps, masking the amount we wanted for the various materials. The skin was more subtle and fine than man-made materials. Glossier materials will have more impact than rough ones, details will not be overruled by big strokes, etc.

We start with the clean bake from Marmoset Toolbag. Then we run the filter over to create broad, medium, and small stroke patterns, which we then combine and smudge over to break up clean surfaces here and there.

The good thing about doing this in the texturing stage is that we are completely non-destructive and can adjust these later on without having to rebake and rebuild all the dependencies from the ground up.

The combined result without diffuse metal or roughness applied:

From there we create a gradient map that will function as a base for base color, roughness, metalness, and so on.

Side Characters

Besides the main cast, we had to fill the background with life. We went for a more low poly direction here and used this task to train two interns on our project's overarching pipeline and project-specific workflows.

Manuel: Our goal was to populate the beautiful settlement scene with a diverse cast of village folks. In order to speed up the process of getting these characters to move and work around the scene, we decided to build them around variations of the standard UE Mannequin rig, which we animated with various animation packs from the Unreal Engine Marketplace.

While sculpting these characters, the focus was on readability, as the locations these villagers inhabit were quite far away from the camera. So creating strong, distinct silhouettes, combined with big motioned animations was the key to livening up the scene.

Lennart: Similar to the main cast, our seven characters share a morphed low poly head. On top of that, we also reused existing meshes and textures where possible to speed up the workflow. To help with the rigging, we created them from the ground up with facial expressions. This would save time on posing them later on while giving the townspeople a bit of character. The great variety of concepts we could choose from really lead to a fun task that would stay fun and exciting.

Creatures

Victor: For the creatures, we tried to have a mix between organic and stylized sculpt. Creature and Concept Artists worked together to obtain the best result. The sculpting workflow was pretty straightforward: defining the shapes and proportions for the blockout and adding more and more details for the final look. We used a lot of references, from whales to prehistoric creatures.

As for the textures, the workflow was the same as the human characters: a combination of stylized normal maps and various brushstrokes to give this painted aspect.

Conclusion

In conclusion, working on something of our own, while a lot of fun, was very challenging alongside our day-to-day business. But it was great to venture into new workflows, trying out and scrapping ideas. We would love to work more on this to figure out how to do all this in Substance 3D Painter, Blender, or maybe even Houdini without the need to process through the filter a few times and mix the results, to gain more control over the brush strokes and flow, etc.

A custom lighting model would be interesting to play with, for sure. It would be great to one day achieve visuals similar to Arcane with dynamic lighting, controlling the painterly feel on the artist's level but maintaining the ability for dynamic specular highlights and reflections.

If you guys have any questions regarding the work on the showcase, feel free to reach out to us. We have an active, very old, thread on Polycount you could use to get in touch.

The Airborn Studios Team