Creating Realistic Hi-Fi RUSH's Chai in ZBrush & Substance 3D

Introduction

Hello, my name is Seunghoon Roh. I have nearly 20 years of experience in the gaming industry and have worked in various fields, such as PC online games, mobile games, and console games. My journey as a 3D Artist began with a passion for gaming. I have always loved playing games, which sparked my desire to be directly involved in creating them. I developed the necessary skills as a 3D Artist mostly through self-studying. YouTube tutorials and other online resources played a major role in my learning process.

Inspiration & References

I decided to create fan art of Chai, a character from Hi-Fi RUSH, because I was deeply moved by the game and found it incredibly fun. When creating the fan art, the most important thing I focused on was how to redesign the character without ruining the original image. I decided to keep as much of the original character's appearance (such as the facial features and outfit) as possible while adding my own design to the mechanical parts.

By taking this approach, I was able to maintain respect for the original work while adding a unique interpretation to my fan art. I believe this balance is key to creating fan art that reflects a deep affection for the original game. The effort to stay true to the source material while offering something new is a testament to the passion of a fan.

Face

The face and basic body were initially created using Epic Games' MetaHuman Creator. First, I adjusted the large shapes to create the base face in MetaHuman Creator and then exported it to Autodesk Maya.

After exporting from Maya, I modified the face in ZBrush. The main task was to reshape the facial expression, and as you know, Chai's face is that of a young person, so I didn't add extra wrinkles or work on fine details in ZBrush.

I exported the work done in ZBrush and used the MetaHuman facial rigging plugin (Meta Pipe) in Maya to set up the face to create facial expressions.

Hair

For the hair workflow, I first analyzed the character's hair and created a rough dummy in ZBrush to get a sense of the overall look and feel.

Reference image:

Next, I modeled the hair according to the hair dummy guide and created an IMM Brush to place each strand individually, making adjustments as I went along.

By placing and adjusting each strand individually, I achieved the final result. I chose not to use the hair card method for this project because I wanted to blend realism with a stylized graphic look. Therefore, I opted to work with a stylized approach for the hair.

Body

I used the default MetaHuman body as the base. Since the character in this project has mechanical parts attached to one arm and the chest, I first created a mechanical dummy for those areas in 3ds Max, aligning the joints with the default MetaHuman body.

After completing the dummy work, I proceeded with detailed high poly modeling using both 3ds Max and ZBrush. For the arm, I used kitbash meshes while simultaneously doing hard surface modeling in 3ds Max. When using the kitbash meshes, I ensured they stayed within the dummy's shape, carefully selecting and placing pieces to maintain the original design as much as possible.

Clothes

I chose to recreate the original outfit, aiming to blend a stylized look with a touch of realism. First, I used Marvelous Designer to create the basic shapes of the clothing.

Reference image:

Next, I imported the data from Marvelous Designer into ZBrush to work on the finer details. I added texture and stitching details, and for areas that were difficult to create in Marvelous Designer, I used ZBrush or 3ds Max for additional modeling and sculpting to complete the outfit. The shoes were created using ZBrush with the IMM Brush.

Cat & The Weapon

For the cat, I made slight design changes from the original image. I wanted to add a touch of realism to the stylized design, so I incorporated some minor mechanical elements while keeping the rest of the design true to the original.

The original weapon is very complex and has a highly stylized design. I didn't want to stray from the original look, so I modeled it in 3ds Max using the original blueprint as a reference. I decided not to use a high poly model, as I wanted to convey the details through texturing, which I will explain later.

Retopology & UV

After completing all the high poly work, I needed to perform retopology to create in-game assets. While various programs are available for this, I used ZBrush's topology features for the task.

After completing the retopology, I moved on to the UV mapping. Since this is a personal portfolio project, I didn't pack everything into a single UV map. Instead, I separated them into individual maps for the head, body, hair, eyes, top clothing, pants, arm, accessories, cat, and weapon.

Texturing

I started the texturing work in Substance 3D Painter. Before beginning the texturing, I first performed the baking process. Then, I moved on to the body and hair. For the head and body, I began with the default textures from MetaHuman. Since the base textures already have excellent detail, I used them as a foundation and added additional skin tone and details to enhance the look.

The clothing texturing process was the most challenging part. I wanted the material to have a realistic feel while still maintaining a stylized look. Additionally, I aimed to create clothing that would blend well with high saturation, which made the process even more difficult. One solution I came up with was to use realistic materials but emphasize higher saturation for both the shadows and the clothing. I specifically chose to increase the saturation even in the shadowed areas of the outfit.

As for texturing the cat, the high level of material detail initially made the design look cluttered, and the cute feel was lost. To fix this, I simplified the color representation and mainly focused on the roughness maps. However, I worked on the material detailing for the metal parts on both sides to create a strong contrast.

The arm mechanics were made in the following way. Apart from the red parts, the arm is divided into simple two-tone colors. This two-tone color scheme helps simplify the detailed mechanical structure. Unlike the clothing, I chose not to add shadow effects to the diffuse texture. Since combining metallic effects with shadows would make the dark areas appear even darker, I decided to leave out the shadows for this part.

I used the PBR method for the metallic parts of the weapon, while the painted sections were worked on by adding shadows and highlights to create distinction. Lastly, I added outlines to give the weapon a more stylized look. For the outlines, I used the Edges Strong function in Substance 3D Painter's masking tools to achieve the desired effect.

Rendering & Lighting

I always start by rendering in Marmoset Toolbag 4, and then I do additional rendering in Unreal Engine 5. I've only worked in Marmoset Toolbag 4 for now, so I'll explain how I set it up there. First, I set up the camera, as shown in the image:

As for the lighting setup, I used a total of four lights:
•  1 Key Light
•  2 Rim Lights
•  1 Fill Light
•  1 Skylight.

When setting up the lights, it's important to start from a completely black screen, with no lights at all. First, I place the key light and check if it works well, then I deactivate it. Next, I place the rim lights, check their effect, and deactivate them as well.

This process is repeated until the lighting setup feels right. The reason for this approach is to ensure that each light – whether key, rim, or fill – has the appropriate position, intensity, and color. After that, I activate all the lights to review the final result.

Reference images:

Conclusion

This project took me about a month to complete. Since I worked on it during my personal time after company hours, it took a bit longer to finish.

When creating a portfolio, I usually focus on fan art or personal designs. I try to emphasize elements that differ from the original. If you're making fan art, simply recreating the original design can lack appeal. I believe it's important to incorporate my own design into the portfolio as much as possible. This not only makes the work more interesting for me but also, if a hiring manager sees it, they are likely to be more intrigued by the unique design elements I've added.

Personally, I believe that maintaining a mindset of continuous effort is essential. Technology evolves rapidly, and there are many highly skilled professionals in the field. To keep up, it's important to stay responsive to new techniques and dedicate ample time to improving and growing as an artist. I also think it's crucial to learn from others' outstanding artwork, drawing inspiration from them to further develop your own skills.

Thank you!

Seunghoon Roh, 3D Artist

Interview conducted by Gloria Levine