Deus Ex Human Revolution Character Artist Sébastien Legrain talks about the creation of the hugely anticipated prequel to one of the most loved action rpgs of all time.

As we’re putting the final touches on this interview, Deus Ex: Human Revolution is about to hit store shelves worldwide. By the time the interview goes live, it’ll be here and many of you will have already begun your exploration of its rich environments and storyline. Developed by Eidos-Montreal, the hugely anticipated game was released on August 23, 2011.

For those not familiar with the franchise, Human Revolution marks the third title in the first-person RPG series. While it is the most recent title, it is actually a prequel and set 25 years before the original title.

Today we are pleased to bring you an interview with character artist Sébastien Legrain – best known on ZBC as sebcesoir. A long-standing advocate of ZBrush, he has never been shy about sharing his techniques with the community and that is reflected in this interview. We hope that you enjoy it!

Eidos-Montreal is quite a new studio in the city. It’s been crazy, exciting and challenging! We started with an empty concrete office space and maybe 5-6 people. They had to build a friendly environment and hire a complete development team able to produce AAA games almost from scratch.

That’s quite tricky since Montreal is getting competitive. All the more so when people haven’t worked together before and the game is being built with a technology that is different from common engines, like Unreal. But Eidos-Montreal has grown a great deal since its conception and I think Deus Ex: Human Revolution proves its success!

Having originally planned to work in the film industry, I moved with regret to video games because of a lack of opportunities. That turned out to be a lucky break, actually! Since the arrival of next generation consoles like Xbox 360 and Playstation 3 the gaming industry has gotten very similar to film. Both use similar techniques with high poly modeling, sculpting and increasingly complex lighting.

I was in Australia, wanting to come back to Montreal when David Anfossi gave me the opportunity to join the Deus Ex team, and be part of the studio’s adventure. I then accepted leadership of the team to structure the different areas: main character/NPC production, pipeline, as well as working with the outsourcing team).

Yeah, I’ve always been fascinated by reproducing humans in CG in the most realistic way possible. What has now become rather common since the arrival of ZBrush and advanced rendering using subdivision surfaces was considered like a Holy Grail a few years ago. But even now I still love to make simple but accurate and elegant, realistic faces.

Sure, the size of the team changed during the production to five people (including myself):

• Arman Akopian, who was a colleague at Ubisoft and is now specializing in concept art.

• Laura Gallagher, a talented artist fresh from school who rapidly evolved to work on a lot of the main characters and complex mechanical elements.

• Tony Yang, who collaborated with Arman in the past, worked on some main characters and NPCs.

• Steven Shmuely, who worked at Ubisoft on games like Prince of Persia. He’s now a character modeler on Thief.

There were two major targets for this project. The first was to respect as closely as possible the art direction from the franchise’s history. We had very accurate concept art I wanted to respect, as well as the visual of the released game. We decided not to go in a photorealistic direction, but more stylized. At the beginning we went for something very stylized, getting close to cartoon-like but it didn’t work well in 3D. Especially in real-time! So we had to turn it down a bit. It’s somewhat similar to Burne Hogarth drawings in that it’s accurate anatomically but some edges of the facial structure are accentuated and sharper.

The second goal was technical. We had very hard technical constraints. We have quite expansive city streets where we can talk to any character. So we had to be able to display a lot of characters, which meant they should be optimised to the maximum amount possible.

We had two major types of characters: main characters (dialogue/story characters, bosses) and general NPC’s (non-player characters).

Main characters are rarely seen together in the game and usually in closed environments. This allowed us more freedom in terms of memory. They can be much more complex and unique.

For the NPC’s, you are able to see many characters plus enemies of different classes, all in big environments with long distance display. That meant very high memory restrictions to get everything in the scene.

In order to be efficient, we decided to make multiple faces reusing the same base textures (diffuse/normal). Variations were made in the shape, the hair and in the shader. This allowed skin tone variations, decal variations (like the possibility to add scars) and different types of eyebrows including adjustments in their position.

For the body, outfits were made of kits. With only one 512 normal map, you must be able to produce a huge diversity of outfits. This texture contained a base model -- let’s say a jacket -- and a small collection of pouches, straps, collars, etc. So when you make a model, you can add different pouches, change the length of the sleeves etc.

In addition, we have very powerful shaders. We use tiny textures that tile to add fabric patterns and normal map details.

This technique has a few disadvantages. It’s a bit tricky to handle. Faces look more generic; you have less freedom than when you make a custom unique head. And for the clothing, since we often cut and combine normal map parts, it makes sharp edges around those details.

But despite that, the advantages are huge. It’s extremely memory efficient. It also allows almost infinite diversity and once you’ve made the base normal map kit it’s much faster to produce new outfits. Also the use of detail maps allows having micro details on characters when you see them from close up.

I used mostly masking in 3D. I’d either paint the mask by hand or drag a custom alpha. I then use a brush with large size or TransPose to move portions of the model, leaving the geometric shaped carved in.

Everything else is done in PM. I enable Double Sided and Normalized with the Single Layer brush to draw assembly lines that will slice the whole model with a constant depth. One thing I love in this mode is that after you’ve drawn a stroke you can move it, scale it or adjust its depth. Another cool technique is to use ZSpheres. This way you can quickly paint tubing and interesting wires.

The major advantage of PolyPaint is to be able able to texture without thinking about the UV’s. You can also convert a texture into PolyPaint, change your model’s UV mapping and then transfer the texture back.

We used PolyPaint heavily to project our concept art directly on the model’s face to quickly get a good base, adjust the shape or as feedback to the concept artist. You advance quickly this way.

The primary use of MatCaps is of course for rendering. That sounds obvious, but when it comes to validation time you would be surprised how a good render can make a difference.

Being able to render advanced shaders simulating flesh or more complex materials like reflecting metal, bronze etc. in real-time and also with real-time shadows is a big plus.

In terms of pipeline, it’s really great to be able to use cavity as masking. You can either sculpt this way or convert it to a texture (such as a specular map for wrinkles).

Also, even if it’s not 100% accurate you can bake MatCaps into a texture. I made a small tutorial a long time ago about this technique, using displacement maps, but you can also use ZAppLink for this. I actually use this technique a lot to quickly make textures.

We often also use the NormalMap shader to quickly make geometric elements like bolts and seam lines which we then integrate in Photoshop to our already existing texture.

TransPose is really a major addition to ZBrush. First, it’s great to adjust character proportions in real-time. This becomes essential when you want to validate characters’ proportions. Most times when you see a character in a “T” pose, something is wrong and you can’t put your finger on it. It’s often because this pose is the least natural possible. Putting a body in a more organic pose with asymmetry and bit of attitude makes a world of difference!

Even just a bust: Take a rigid symmetrical bust for the shoulder, turn the neck of your character and make him look from an angle and it will instantly bring him to life.

I’ve been using ZBrush for maybe 6-7 years now. It was the first sculpting program able to handle millions of polygons on regular PC. Today it’s still the most advanced of its kind and the 2.5D technology makes it unique. Sculpting is the most appropriate and intuitive way to create organic shapes – much better than moving vertices. Being able to create complex and detailed models in a short time makes ZBrush essential in video game production.

A typical day starts around 9:00 (or 8:00 if you want to leave early). When we arrive, it’s cafe time. We discuss recent news, what gadget we just bought, what film we’ve seen or game we’ve played.

It’s been more than 5 years now. I still love Montreal. It’s a very relaxing city. People are easygoing and there’s great night life, good food, markets etc. There really are a lot of activities to do, even during the long winters.

It’s great to have a lot of studios here. There’s less pressure on people to leave or lose their job. It somehow helps to build a videogame/artistic culture here, which benefits everyone -- both employees and companies.

From the beginning the aim of the studio was to grow, but to keep it a human size and to try to maintain a certain “family spirit”. Of course we are here to work and the aim is to make high quality games that sell well, but we stay small enough to know most people and be able to organise activities like soccer, etc.

At each studio meeting, Stephane D’astous (our GM) takes the time to introduce any new employees. It’s nice, even if it takes a while when people are impatient to get the traditional Friday beer!