Jan. 12, 2021, by Alena Dubrovina and Koen Van Mierlo
Bringing Life to Legends: Character Art in Baldur’s Gate 3
Larian Studios discusses PBR, custom shaders, and the creation of awesome character art for Baldur's Gate 3!
Compile a list of ‘best CRPGs ever made’, and the Baldur’s Gate series will probably appear on there. Baldur’s Gate II: Shadows of Amn might look a little turn-of-the-millennium these days, but it still demonstrates everything an RPG should have – expansive locations, intriguing NPCs, and diverse character development. Yet the series has largely been on hiatus for the last two decades. Continuing such a well-loved franchise would surely require a studio with some serious development chops.
Enter Larian Studios. Larian has gradually been establishing its credentials as a maker of outstanding CRPGs, notably with the release of 2017’s Divinity: Original Sin 2 – another game that appears on many ‘best of’ lists. Larian therefore seemed an ideal choice to partner with Dungeons & Dragons IP holder Wizards of the Coast, to take on the next entry in the Baldur’s Gate franchise.
In October 2020 Larian released Baldur’s Gate 3 in Early Access. Alena Dubrovina and Koen Van Mierlo, respectively Lead Character Artist and Technical Art Director at Larian Studios, recently took the time to detail their ongoing work on Baldur’s Gate 3, and how Larian uses the Substance toolset in its pipeline.
Artwork courtesy of Larian Studios
Relativity of color: this line has one value (50% gray), but it looks like a gradient.
In this photograph, the blue sheet and the pink bin stand out. But if we only look at the values , the blue sheet has the same value as the wood it’s lying on. The pink bucket has a darker value than the wooden frame next to it.
When artists make beauty shots, they usually select a really dark background, with a spotlight, in order to improve the overall look of the asset. But this doesn’t always help you to clearly define the proper PBR values. And, actually, trying to convey these concepts to artists is a full-time responsibility,
I think it’s really important that people understand the concept of PBR. If they don’t understand it, they won’t be able to get their art moving forward. They’ll stick to only trusting their eyes, and that’s something you shouldn’t do, especially with PBR, because your assets can look completely different in different lighting conditions. If, for instance, you have snow, that should look like snow whether you’re observing it in the evening, or in full daylight, or in a dungeon.
The easiest way to check your values is to use a histogram, and compare them to values you already know. Sébastien Lagarde’s chart is a really good starting point:
Artwork by Sébastien Lagarde, and courtesy of DONTNOD Entertainment
This color chart is not meant as the de facto colors we need to use. Instead, it should be used as a frame of reference to help artists define correct values for their assets, the darkest substance being coal and the brightest being fresh white snow.
Artwork courtesy of Larian Studios
I added the DONTNOD color chart in the engine. The value shift from dark to bright is clearly visible in the grayscale version.
In Substance Painter the value and levels look like this:
Notice the big difference between snow (243sRGB) and 222sRGB, both in the value slider and in the levels tab, even though, numerically, these values are quite close to one another.
Alena: In addition, when you have a lot people working on one project, it’s hard to keep things consistent. With cloth, for instance, you can have a wide range of PBR colors, but if one person always makes them really dark, and another one keeps them bright, when you preview them in the engine they won’t match. And this is true of clothing, armor, vegetation, environments, and so on – if all your artists are doing their own thing, and making their textures the way that they personally think they should look, then there are no rules and the final result won’t come together. We struggled with this in DOS2, and I think we can still improve on this; it’s ongoing work. So you need to establish visual rules – and PBR is an easy, existing guide; you don’t have to come up with rules about how your whites or your blacks should look, because that’s already defined by PBR rules.
Artwork courtesy of Larian Studios
With characters this is more challenging. Eyes, for example, are never going to be PBR. If you’re making a shader for eyes, with a base color map, a normal map, and a roughness map, they aren’t going to look right. With eyes we had to come up with tricks to ‘cheat’ the characters’ eyes into looking better in a PBR environment. We use a custom shader for that, and it’s technically still a PBR environment – but there’s a bit of a fantasy aspect in there, too.
Koen: Yes, eyes are indeed the best example of that. We faked the little highlights in the characters’ eyes. Because if they aren’t there, those eyes just look dead. So we needed those highlights. When you’re filming a scene, you can tailor your light depending on what you want to achieve; that’s basically what we’re doing with the shaders for the eyes. We essentially follow PBR rules, but bend them – not too much; just a bit – to make the eyes look better.
Another example would be silk. Silk has a colored specular. You actually need to make it look slightly metallic; your metallic map needs to be gray for it to look like silk. If I say that to a programmer, it’s completely wrong, it’s against the rules. But it’s the only way to make this material authentically look like silk.
Sometimes it’s quite a balancing act between precisely following the rules, and deviating from the rules just enough to make things look better.
Note that further information on physically based rendering can be found in The PBR Guide, on Substance Academy.
Alena: We did a lot of research for Baldur’s Gate 3 – we didn’t just jump in and assume we’d get everything right. We carried out an analysis of other games on the market, the kind of things they were making, how they approached texturing, and so on. We even looked at what sort of information they’d include in their base map, things like that. And we also looked at what we’d done previously in DOS2, and asked ourselves how we could bring this up to another level.
The challenge here is to realize that you need to tailor your tools, whether that’s Substance Painter or another tool, to meet your needs. You shouldn’t just look for something that’s already figured out. Also, you can look at things like tutorials that will explain how to do skin textures – but this sort of information is rarely applicable for commercial projects, because you’re always going to find yourself in a unique scenario at some point. Instead, you should focus on how you want something to look for your project, and break down the steps necessary to achieve that.
It can be hard to figure out exactly where to start at the beginning of a project. If you’re working with Substance Painter, for instance, you’re never going to start by building a complex shader for future color customization when you don’t have any context. The content and the design needs of your project should always come first. Analyze your designs to build the proper customization systems that will not only maximize the content, but that will be well-integrated into gameplay systems, so that they can contribute not only to the visual look but also to the player experience.
Even though we already had well-established pipelines in DOS2 we realized that they wouldn’t be sufficient for BG3. We had to carefully plan a new roadmap of features and revamp most of our character pipelines in order to be able to keep up with the industry standards.
Overall, I believe that planning, prototyping, and innovation are the main pillars of success for any personal or commercial project.
With this approach, instead of having one base color map we ended up with four maps: hemoglobin, melanin, vein, and yellowing maps.
Below are examples of the properties of the map being changed in the material, which gives us a lot of flexibility for varied textures using the same maps. An example from Substance Painter:
Meet Koen Van Mierlo
Koen Van Mierlo is Technical Art Director at Larian Studios. He joined Larian in 2005, and has worked on a range of games including Divinity II: Ego Draconis, and Divinity: Dragon Commander, as well as on more recent titles such as Divinity: Original Sin 2 – Definitive Edition and Baldur’s Gate 3.