Merlin in 3D: Face Textures and Rendering

Introduction

Hi, my name is Adrienne Lange, and I’m a self-taught 3D character game artist based in New York City! I’m excited to present a breakdown of my character Merlin, a piece created for the real-time character portion of Artstation’s Legend of King Arthur challenge. I love the format of the Artstation challenges, especially, the requirement to post weekly updates in a challenge thread; this creates a wonderful sense of community and camaraderie, where you can follow other amazing artists’ progress as well as receive feedback and support from a variety of sources. It’s fascinating for me to see the different pipelines and techniques used by artists, especially artists, who are competing in a different discipline. I would recommend the Artstation challenges to anyone looking to push themselves to complete a character, prop, or environment with some constraints and a community to support you along the way; I would especially recommend it to students or self-taught folks, who want to test themselves against peers and pros in the industry.

In the time since I completed Game Art Institute’s Bootcamp and my last character breakdown, I have been hard at work on my portfolio with the goal of eventually finding full-time game studio work as a character artist. I currently work part-time in an unrelated field, so, fortunately, I have ample time to devote to learning new techniques and creating new characters. It’s a tough balance to pick personal projects that will challenge you enough, but do not take too long to create or cause you to burn out. With each new project, I try to pick one aspect of the character to use to learn new software or skills (e.g. anatomy or hair cards). Merlin was the first character where I was not focusing on learning new skills but instead presenting everything that I learned as a whole.

Concept and approach

When I started looking through the possible character concepts for the Legend of King Arthur challenge, I wanted to find a character concept that was a deviation from the typical knight in armor but that would also be a step up from than the types of characters I had done recently, in terms of complexity. I kept coming back to Marco Dotti’s concepts for their silhouettes and their slightly twisted elements; I eventually chose his Merlin concept for its backstory, emotion, and composition. I love his twist on Merlin, who in this case is not the typical storybook bearded wizard that you might expect, but is instead a sickly, crooked, and malicious figure. I saw a lot of potential in the face in particular, which in the concept is contorted and menacing. Marco helpfully gave me the idea that under his eyepatch is a disfiguring scar from a laboratory accident, which I incorporated into my sculpt. Marco also pointed me to use the actor David Bradley, Game of Thrones’ Walder Frey, as a face reference. It’s immensely helpful to have a well-known and well-photographed face reference to work with, not necessarily for the likeness, but as a good starting point for blocking out proportions.

From a learning/growth standpoint, I chose to do this concept because it was more complex than what I had done in the past and I wanted to push myself to tackle more elements and materials than before. I had previously underestimated the importance of visual composition and complexity and decided that it was time to push myself a bit further in that regard.

Head sculpt

The face sculpt was absolutely my favorite part of this process. I particularly enjoy sculpting older faces; there are so many forms and contrasts compared to younger, smoother faces, and I love the emotion that you can capture with the severity of the expression. I was very inspired by the incredible face sculpts from the team working on “A Plague Tale: Innocence”, such as these by Emmanuel Lecouturier, Loic Paulus, and Adonia Urian (among others).

With these sculpts, the artists were able to capture and communicate so much emotion and information instantaneously, and I was aiming for something similar to Merlin’s face sculpt.

In terms of the actual sculpting approach, I wanted to make the face very asymmetrical and extreme without looking cartoony or stylized. I prioritized the eye area (even though you can only see one eye in the final piece) as well as the scar that runs from the lip to the eyelid; I thought these were the most important areas for giving the haunted, sick appearance that I wanted.

I start out in ZBrush with a very simple base mesh (typically one of the pre-loaded ZBrush meshes) and then establish the main forms and creases of the face, using clay buildup on very low intensity (~10), ensuring that the face looks well proportioned from each angle. Then, I start working on the smaller creases, using Dam Standard and adding weight to the bottom sides of the wrinkles using the Standard brush. Those three brushes, plus the Move brush, are the brushes that I use 95% of the time.

I block in eyeballs early on, with a quick Polypainted iris and pupil. I find that having the iris in place helps ground the face and gives a better sense of the final appearance; I formerly did not paint in the iris and would be surprised further down the process when the face looked strange with textured eyeballs in place. It is very important to have these placeholders early on, not just for accurate sculpting, but so that you can have the most realistic representation possible of what the final piece will look like.

It can be hard to keep a realistic look with such an extreme face, which is why photo reference of old peoples’ faces was essential. Asymmetry is especially important for such an exaggerated face; if the deep wrinkles are identical on both sides, it looks more artificial and therefore less effective. I waited until the very end to break symmetry, just to allow iteration for the main shapes of the face. I sculpted the scar on its own layer so that I could return to the original sculpt if it did not work and try out different versions. I add pore and tertiary details in Substance Painter, so I didn’t need to worry about projecting or painting pores in ZBrush. The only alphas I used on the head sculpt were for fine lip detail; I recommend Todor Nikolov’s lip alphas, which are affordable and high quality.

The scar was sculpted, using the Dam Standard brush and extensive scar reference photos. Skin will scar very differently, based on how deep the wound is and the location on the body, so the reference is crucial. I wanted this scar to drastically alter Merlin’s appearance and contribute to the mood of the project; I found it helpful to keep exaggerating the warp of the scar past my point of comfort, and then to step back from the sculpt to get feedback online. It is crucial to get feedback from a variety of objective sources (peers and pros on Discord servers, Artstation challenge threads, Twitter, etc) as they may see things that you may not ‒ and they have not been desensitized to the sculpt as you might be after looking at it for hours.

High poly sculpt

The high poly sculpt was the most difficult part of the project for me. The torso region of the character has a lot going on: lots of belts, several pieces of studded leather padding, an arm pouch, and, then, smaller metal accessories. I decided to block out all of the clothing elements in Marvelous Designer instead of Maya, due to the layering of the pieces. Marvelous Designer’s layering function was extremely useful in blocking out the placement of the many interlaced belts and for quickly getting base meshes to work with in ZBrush. I anticipated doing most of my detailing in ZBrush, so Marvelous was used mainly as a speedy block-out of the general shapes and silhouette. The only pieces that needed to be simulated in Marvelous were the tunic, skirt, and boot covers, and it was essential to have the leather straps in place for the simulation to interact with and achieve the bunching and gathering of fabric around them.

I follow a common workflow for importing Marvelous Meshes to ZBrush: export with the “Thin” and “Unweld” settings turned on in Marvelous, give the cloth thickness using Panel Loops in ZBrush, and then ZRemesh it to get quads. The key with high poly clothing is to spend far more time in ZBrush than in Marvelous, adding detail and volume to the clothing and exaggerating the folds created in Marvelous. In the future, I hope to push my cloth sculpts even further and focus on memory folds and fine detail in ZBrush; I currently rely on Substance for the bulk of my cloth detailing, but fine creases and wrinkles in the high poly sculpt can be immensely effective for pushing your character the extra mile.

After exporting the Marvelous Designer meshes into ZBrush, I modeled the smaller pieces (vials, keys, boots, rings) in Maya and imported them to ZBrush as well in order to get the full block-out. At this point, the whole piece looked very rough and simple, but it’s important to get all the pieces together and have a glimpse of what the composition and silhouette look like. At this early stage, it is easier to make large changes to the silhouette and add more volume to the exported Marvelous meshes. The silhouette of the Merlin concept is very exaggerated, so I did a lot of tweaking of the proportions towards the end in order to match the hunched shoulders and gaunt frame of the concept. I find it very helpful to take lots of progress screenshots from the same angles, typically at the end of each working day, in order to compare and contrast changes.

Texturing

Leather

I did all of the texturing for Merlin in Substance Painter. There aren’t too many different materials going on in this piece, but the material that I wanted mostly to focus on was the leather. Leather, like skin, relies heavily on roughness and chromatic variation to look believable. There are a lot of overlapping leather pieces in the torso area, and I wanted to make sure that they did not blend together or get too messy. I used a lot of photo reference as well as references from other 3D pieces to understand the unique ways, in which leather creases or wears down, and how to portray this. I loved the Artstation art dump from Metro Exodus since there were so many leather jackets and belts to look at and to draw inspiration from. Eugene Gottsnake’s leatherwork from Metro Exodus is a wonderful reference.

The leather for Merlin’s belts studded guards, and the chest piece all have slightly different color tones and levels of wear in order to distinguish them. I did a lot of manual painting on the belts in particular in order to fine-tune the wear at certain points, such as under the buckles and edges. I also do a lot of hand-painted detail layers to avoid getting a result that looks too “procedural”, though it admittedly takes longer than using a smart material by itself. All of my manual painting is on black masks applied to fill layers so that I can easily tweak the fill parameters. The general layer breakdown for each leather component was the following, in ascending order:

• Base material layer (in this case, Substance Source’s Plain Leather material)
• Dirt generator with a dark, contrasting color (such as a deep purple or red)
• Small scratches at wear points, with lighter brown color
• Larger individual scratches with light brown color
• Splatters of mud/blood
• Edgewear generator with a lighter color
• Color variation layers – contrasting color on very low opacity
• Dirt gradient

This leather material stack is the typical layer order for most of my materials; a base, shadow, highlight, and then painted details.

The Hand

I approached the texturing for the prosthetic hand similarly; I wanted to capture the rusted, aged look from the concept and make sure that the material reads clearly from a distance. As with the leather, I tried to use bright colors that seemed almost exaggerated in Substance Painter’s viewport, because they will look very different in Marmoset with proper lighting setup. It’s important to work back and forth between Substance Painter and an engine to understand, how the material presents in both settings.

The hand is composed of a stack of layers of a rust material fill, set to varying colors and roughnesses, on top of a base grey iron material:

Face

I created tertiary and pore detail for Merlin’s face using Texturing XYZ displacement maps projected in Substance Painter. I created a fill layer with height only, add a black mask, and then paint on the black mask over the projection to achieve more detail. After projecting the three TexturingXYZ maps on different layers, I fill in the gaps, using Substance’s pre-loaded skin materials.

It was important that Merlin looks very sickly and haunted, so I did a lot of iterations with his skin tone, trying to achieve a balance of color without the face looking too drained. However, if you look at my layer stack for the face, there aren’t a lot of peachy skin tones; rather there are a lot of bright color layers that are on a low opacity. I added several layers of purple and blue tones under the eyes to emphasize the character’s sickliness. For all of my characters, I tend to stack saturated color tones in order to avoid a waxy, flat look. It may look a bit clownish or extreme in Substance’s viewport, but once subsurface scattering parameters are set up in Marmoset or an engine, the colors settle and look more natural.

The texturing for the face sets a good base, but the shader setup in either Marmoset Toolbag or an engine is crucial for achieving the final effect. As with my Wise Woman character, I closely followed Saurabh Jethani’s skin setup tutorial for Marmoset Toolbag. Getting the subsurface scattering and roughness parameters correct is essential in making the skin truly look like skin. Often you see subsurface scattering cranked all the way up and the skin looks like candle wax, or subsurface scattering is missing altogether and the skin looks like dried orange peel. It’s best to stay with a scatter depth of 1.0 – 1.4 mm for realistic skin; I usually stop the slider when the creases of the face start to soften.

Marmoset setup/lightning

I use Marmoset Toolbag for presentation for several reasons; Marmoset is easy to learn, allows you to set up your maps and shaders quickly and has very high-quality lighting and soft shadows. It doesn’t take very long to set up a solid basic lighting setup and achieve a good result, though it does require fine-tuning. It doesn’t quite line up with the practical functionality of a real-time engine such as Unreal, but it is a good choice for quick lighting setups, renders, and baking.

When it comes to lighting, I think it is important to consider the mood of the character and the concept piece. Since Merlin is a creepy, evil character, I wanted the lighting to match; I used dark green-yellow tones for the background and a yellowish fog to disperse the scene lights.

If you use fog in Marmoset and play around with the “Lights” slider (under Illumination), you can achieve a glowy ethereal effect using moveable lights in your scene. I set the fog color to bright yellow and placed several spotlights behind the character’s head and torso facing away from him to make a quick glow for renders from the front view.

The rest of the lighting setup followed a typical 3-point light setup: a key light, fill light, and backlight. I wanted Merlin’s face to be severely lit, so there are several lights above the head pointing down to get sharp, high-contrast shadows.

For the spark effect, I made a small plane in Maya, painted a yellow-orange blurred circle on a transparent background in Photoshop and placed the planes around the character with varying sizes and orientations. These small touches can make the render more compelling, especially in an important render such as a project thumbnail; if I had more time I could have taken one step further and created a pedestal or a quick environment, but I wasn’t able to do so with the time constraints of the Artstation challenge.

I have only recently started playing around with Marmoset’s Post Effect settings, and I highly recommend it. It is a huge time-saver and instantaneously allows you to change the tone of the renders. My renders for Merlin were primarily high-contrast with a black vignette to emphasize the yellow glow.

Afterword

This character was a fun way to push me, considering the time and technical constraints of the Artstation challenge. I would highly recommend the challenges to anyone who has the time to spend on it and a desire to push their skills a bit further! The community is an amazing resource for artists of all levels, and I look forward to the next one. My greatest thanks to Marco Dotti for permitting me to use his concept, and many congratulations to the challenge winners and competitors!

Adrienne Lange, 3D Artist

Interview conducted by Kirill Tokarev