Look How V from BTS Was Recreated Using UE5, ZBrush & Substance 3D Painter

Introduction

Hello everyone! My name is Helena Shin, a Senior Character Artist from South Korea. I have experience working as a Character Artist in the game, VFX, and animation industries from 2006 to the present. I'd say that I have a different career path than other artists.

From 2018 to the present, I have given several webinars at Adobe Korea and Autodesk Korea, lectured at universities, appeared as a special guest on YouTube CG channels, and published the world's first texturing XYZ book in February 2019. I think it was really amazing, wasn't it? This wonderful life I have lived is my pride.

The first time I started doing 3D art was when I was relearning the 3D subjects I had failed in the university at a local CG academy in 2004. There I learned basic modeling, as well as CG techniques, such as texturing, rigging, key animation, lighting, and pre-rendering.

Recently, I have participated in digital human projects at a game studio. Also, I plan to work on real-time projects related to Unreal Engine 5 in the future.

The Story Behind Kim "V" Tae-hyung's Portrait

Now is the era of real-time content. That's why I decided to use Unreal Engine 5 to create a real-time character for my career in the future. Especially for this work, I wanted to create a male character rather than a female one. The reason is that many artists create young female characters using pre-rendering, but I decided to differentiate myself from them. Then, while looking for a good model with my inspiration, I chose V, a member of the world-renowned boy band BTS.

Above all, V is handsome and has the image of a cross between a boy and an adult man. Therefore, I thought it was an opportunity to create work with a different atmosphere from other artists, and I started working on it.

As for the concept, the subtitle of this work is "BTS'V x Thom Browne". As you know, in this work, V is wearing clothes from the world-famous brand Thom Browne. It seems that many artists tend to leave out the design elements of costumes and just make them well. However, whenever I create a work, I think the character's costume design is important, so I always pay attention to it. Then, I remembered that BTS had been photographed wearing Thom Browne before. So, in this artwork, I focused on a clear concept of V as Thom Browne's ambassador.

Modeling

The modeling pipeline was similar to other artists. However, this time I created it a little differently. This is because I used the metahuman mesh. First, a head and body were sculpted based on the scanned mesh, and then these were retopologized using the Mesh to MetaHuman tool in Unreal Engine. Later, I did detailed sculpting in ZBrush on these meshes.

Also, the hairstyle was created using a hair card, not a hair groom. This is because it is still too heavy when the character moves in Unreal Engine to be used as a groom. So, a hair card was used to control this in software more lightly.

In order to approach likeness, I collected reference photos of V, which seemed to have been taken with many cameras with a focal length of 85mm, and worked on the head based on those. Here, since the shape of the face appears slightly differently depending on the photo, standards, and settings for the camera focal length of the photo are necessary. To do this, it's good to set a standard focal length and then gather reference photos and work accordingly.

As for reference work, photos of many boy bands mostly have clean skin that has been retouched using Photoshop filters and tools. In fact, their skin is very realistic. But if I make their skin look really realistic, a lot of fans would really hate it. So the only reference I had was mostly pictures of him with clear skin. As you know, CG, on the other hand, needs to be expressed realistically to be well-made. So, I worked on it using a mix of references and my texturing skills. I approached the skin detail work a little cautiously. The reason is that Kim V's skin is softer than that of an average adult man and a little rougher than that of an adult woman. So, I did not express it too roughly when expressing the skin's detail.

To create eyes, I used metahuman eyes. In my previous work, I designed and created the eye mesh and texture from scratch. However, this time, I chose a simpler and more efficient approach. The decision was mainly influenced by the remarkable quality of the textures and materials available for metahumans.

Above all, a lot of effort was put into the clothes in this work. Basic modeling was done in Marvelous Designer, followed by detailed sculpting in ZBrush, and finally, the model was retopologized in Maya. Lastly, the clothes were modeled with medium-quality mesh. 

Retopologizing and Unwrapping

Both the body and head meshes were retopologized using the Mesh to Metahuman tool in Unreal Engine 5. The good thing is that you can later download the automatically rigged body, head mesh, and rig data from Metahuman Creator as a Maya file via the Mesh to Metahuman tool.

I am also particularly fond of the convenience provided by the automatic metahuman facial rigging system, as it empowers character artists to effortlessly generate a wide range of facial expressions without requiring advanced rigging skills. Therefore, I believe that the facial rigging capabilities of metahumans are their greatest advantage and standout feature.

Also, the clothes were retopologized and unwrapped in Maya. I always use these tasks only with Maya because its retopology tool is easy and convenient, and allows for various tasks and continuous modification within it. Additionally, the biggest feature of Maya is the UVs unwrap, particularly, the unfold and straighten tool in UV Editor is really powerful. So, whenever I do this work, I always use Maya.

Texturing

To achieve the desired skin texture, I utilized the Albedo and DisMulti (Displacement) textures provided by VFace. These textures were then transferred onto the retopologized head mesh using the wrap 3D technique.

The wrapped DisMulti texture was added as a layer in ZBrush and applied to the Displacement Map to create detailed skin.

Detailed skins applied in ZBrush were exported to high-resolution and low meshes to bake normal, cavity, and ambient occlusion textures in Marmoset Toolbag 4.

I chose to utilize Marmoset Toolbag for baking these textures due to its speed, cleanliness, and clarity, which surpasses other software options. After baking the ambient occlusion texture, I imported it into Substance 3D Painter and applied a multiply layer to introduce shading effects onto the skin. Additionally, the baked cavity texture was incorporated into Unreal Engine's metahuman head material to control the specular reflections within the skin's pores. This can be easily accomplished by applying the texture directly to the cavity tab displayed in the material settings. The process is incredibly straightforward.

Then, detailed basic color texturing was done in Substance 3D Painter. No special skin brushes were used for this head, just the built-in default brushes because this software's brushes are really great.

Following that, I implemented the basecolor, normal, and cavity textures into the metahuman head material. The eyes were not worked on separately, and the metahuman's mesh, textures, and materials were utilized as they were.

The hair was made with hair cards. I created several hair samples using XGen in Maya, then baked AO, depth, flow, normal, and root textures with Arnold. The Diffuse Map was not baked because the hair color was set by selecting a solid color from Unreal Engine's hair material. This is because Kim V's hair color is black to dark brown, so a solid color looks more natural. Regarding the flow and normal textures that were baked, they were exclusively employed within Unreal Engine as flow textures. This decision was made due to the fact that the flow texture serves as a Vector Normal Map.

For the texture of the clothes, I did base texturing using Substance 3D Painter's basic fabric material, and then did the rest of the detail texturing myself. For texturing, I used Mari until a few years ago. But these days, I am only texturing in Substance 3D Painter. This is because it can produce decent output just by using basic materials. Above all, this is because the Substance 3D Painter's official site provides users with decent materials. I also use the default brushes built into this software to work on skin textures.

Realistic texturing is possible just by using this, so it's really convenient because I don't have to use a special brush.
This is why I only use Substance 3D Painter for texturing.

Rendering

I captured images from the camera scene in Unreal Engine using the screenshot capture function. It's important to note that these images depict a cinematic real-time view, and they are not rendered using path tracing within the software.

In terms of lighting, I incorporated two types: HDRI and spot lights. The intention behind this choice was to maintain a simpler approach.

Additionally, I did not make any adjustments to post-production settings. Everything remains exactly as it was originally configured within the engine. That concludes the process.

The trick with rendering realistic characters is that it's not just about texturing and modeling. Depending on the lighting, the character's face may look different, and the skin's texture may appear or disappear.

That's why lookdev, which includes lighting, holds significant importance in rendering. Additionally, tone mapping plays a crucial role within the lookdev process. The reason for this is that the character's quality and atmosphere can vary depending on how the tone mapping is implemented. It is my belief that, in order for character artists to progress and improve, it is essential to dedicate ample time to studying Lookdev.

Reflecting on this, it becomes apparent that there are numerous areas a character artist must delve into and study in order to excel in their field.

Final Words and Pieces of Advice

It took about a year to finish everything. The reason for the extended timeline was primarily due to my first-time usage of Unreal Engine and the fact that I worked on it at home during my free time after work. Speaking of the challenges encountered, the main difficulty in this project was mastering Unreal Engine. In order to overcome this obstacle, another challenge was resisting the temptation to utilize Marmoset Toolbag and Arnold for path-tracing renders within Unreal Engine. However, with patience and perseverance, I successfully completed the real-time character using Unreal Engine. This endeavor was both demanding and significant for me, and I find solace in the fact that I was able to overcome it successfully.

My advice for aspiring character artists is: "Just do it!" This is what I want to say to artists at all levels. I sometimes saw people running away or doing nothing because they were afraid of failing before they even started anything. But the failure I think is doing nothing. Please just do it. It doesn't have to be fancy or grand. Above all, don't compare yourself to famous artists because they were nothing at first, too. So don't be afraid and start with the little one. Of course, your work may fail, but over time, it can be a turning point in your life or a secret weapon at a critical moment in your career. I have experienced this myself from 2006 to the present. Don't worry, just do it. Always believe in your own greatness and strive to progress further. You can do it. And eventually, everything will be fine. I promise you.

Helena Shin, Senior Character Artist

Interview conducted by Theodore McKenzie