Behind the Scenes of Infinity Nikki: Tracing a Glamorous Turn to an Unreal Open World
August 23, 2024
Weibo Xie is the VP of Technology at Infold Games, overseeing the development of UE-related engines, technical art, and artificial intelligence technologies. He has pioneered multiple innovative technologies implemented in Infinity Nikki. Previously, Weibo Xie served as a Senior Expert Engineer at Tencent, where he contributed to projects like Moonlight Blade and real-time digital character “Siren".
Among the many genres of video games, open-world titles have seen a significant rise in popularity in recent years, evolving from their early days to garner a substantial following worldwide. Nowadays, when discussing open-world games, one might naturally wonder: beyond exploration and adventure, what other unique features can these games offer to provide a different kind of experience?
Fortunately for players, Infold Games has brought us one such distinctive open-world game. When you think of Infold Games, the Nikki series instantly comes to mind. Since the successful launch of the original 2D game Nikki UP2U: A Dressing Story in 2012, the series has expanded with titles like NikkiUp2U: World Traveller in 2013, Love Nikki-Dress UP Queen in 2016, and the 3D version Shining Nikki-Fashion Makeover in 2019. Through these releases, Infold Games has consistently pushed the boundaries of gaming by integrating new technologies and gameplay mechanics, continually enhancing the player experience and overall game quality.
Fortunately for players, Infold Games has brought us one such distinctive open-world game. When you think of Infold Games, the Nikki series instantly comes to mind. Since the successful launch of the original 2D game Nikki UP2U: A Dressing Story in 2012, the series has expanded with titles like NikkiUp2U: World Traveller in 2013, Love Nikki-Dress UP Queen in 2016, and the 3D version Shining Nikki-Fashion Makeover in 2019. Through these releases, Infold Games has consistently pushed the boundaries of gaming by integrating new technologies and gameplay mechanics, continually enhancing the player experience and overall game quality.
Infold Games is a new international business brand launched by Papergames aiming for global expansion. Established in August 2022, Infold Games has achieved remarkable success globally across multiple countries and regions with its latest installment in the Love Series, Love and Deep Space, which was officially released on January 18, 2024.
Fast forward to April 24, 2024: Infold Games launched the official Whim Playtest for their latest Nikki series installment, Infinity Nikki. This announcement was a pleasant surprise, especially since the project is the first for the developer since switching to Unreal Engine from other engines.
The transition enabled them to break away from the confined spaces of previous installments to develop an open-world experience using Unreal Engine 5. Now, Nikki and Momo are set to embark on a brand new fantastical adventure in a vast "Unreal" world. Just reading about it evokes images of sunlight cascading over endless fields of flowers, with Nikki strolling through picturesque towns and castles, dressed in her finest spring attire.
But hold on! Historically, the Nikki series has excelled in capturing and presenting intricate details within small, studio-like settings. The series is renowned for its exquisite lighting and detailed textures that make Nikki's outfits look stunningly beautiful. Transitioning to an open world in Infinity Nikki means adapting to a larger scale of scene production and integrating numerous technical details, necessitating the use of Unreal Engine 5.
Previously, the focus was on "small-yet-refined" environments, which was relatively easier to achieve. This time, striving for "large and comprehensive" is reasonable, but aiming for "large and refined" poses significant challenges.
Can Infinity Nikki maintain the level of detail and high standards of its predecessors in an open-world setting? Can Nikki, stepping out from the studio into the open world, impress the discerning eyes of players? And most importantly, can the game's slogan "It's glam time any time" ensure that casual snapshots of Nikki are equally breathtaking?
The transition enabled them to break away from the confined spaces of previous installments to develop an open-world experience using Unreal Engine 5. Now, Nikki and Momo are set to embark on a brand new fantastical adventure in a vast "Unreal" world. Just reading about it evokes images of sunlight cascading over endless fields of flowers, with Nikki strolling through picturesque towns and castles, dressed in her finest spring attire.
But hold on! Historically, the Nikki series has excelled in capturing and presenting intricate details within small, studio-like settings. The series is renowned for its exquisite lighting and detailed textures that make Nikki's outfits look stunningly beautiful. Transitioning to an open world in Infinity Nikki means adapting to a larger scale of scene production and integrating numerous technical details, necessitating the use of Unreal Engine 5.
Previously, the focus was on "small-yet-refined" environments, which was relatively easier to achieve. This time, striving for "large and comprehensive" is reasonable, but aiming for "large and refined" poses significant challenges.
Can Infinity Nikki maintain the level of detail and high standards of its predecessors in an open-world setting? Can Nikki, stepping out from the studio into the open world, impress the discerning eyes of players? And most importantly, can the game's slogan "It's glam time any time" ensure that casual snapshots of Nikki are equally breathtaking?
The answer lies in the in-game footage showcased above. Infinity Nikki delivers stunning visuals and a uniquely engaging gameplay experience, capturing the essence of what an open-world game should be and quelling many of the previous doubts. However, our curiosity was piqued by the various questions about the project's development and technical aspects that we had, prompting us to reach out to the Infinity Nikki development team for an exclusive behind-the-scenes look at the making of this game.
Why did you decide to make Infinity Nikki an open-world adventure game?
Weibo Xie, VP of Technology at Infold Games:
Throughout the 12-year development of the Nikki series, we have always aimed to push the boundaries of technology and scale, continuously improving the quality of our products while enjoying the challenge of doing the seemingly impossible. Initially, when we started making dress-up games, many people couldn't understand it, thinking such games were too niche to sustain a startup.
However, through several iterations, we proved that there is a significant market for dress-up games. By enhancing our technological capabilities and scale, we pioneered the 3D dress-up game, elevating it from a small-scale product to an industrial-grade 3D game. When we proposed creating a 3D dress-up game with AAA-quality standards, many thought it was impossible, but we found a way to make it.
How did you bring the art style of the Nikki series to an open-world adventure game?
Xie:
We aimed to present players with a warm, beautiful, and fantastical world filled with whimsical ideas.
The art style underwent numerous trials and validations by both the art team and technical artists (TA). The producer wanted to find the right balance between cartoon fantasy and realism. The lighting model in Unreal Engine is derived from Disney's PBR (physically based rendering) model, so despite the high proportion of cartoon elements, our lighting calculations follow PBR standards. This enabled us to give our models unique styles with realistic texture.
Our artists provided various references, and the TA implemented specific effects to closely match these references. We held weekly art benchmark meetings to align ourselves on the style of art and set a unified tone for the overall art direction.
Weibo Xie, VP of Technology at Infold Games:
Throughout the 12-year development of the Nikki series, we have always aimed to push the boundaries of technology and scale, continuously improving the quality of our products while enjoying the challenge of doing the seemingly impossible. Initially, when we started making dress-up games, many people couldn't understand it, thinking such games were too niche to sustain a startup.
However, through several iterations, we proved that there is a significant market for dress-up games. By enhancing our technological capabilities and scale, we pioneered the 3D dress-up game, elevating it from a small-scale product to an industrial-grade 3D game. When we proposed creating a 3D dress-up game with AAA-quality standards, many thought it was impossible, but we found a way to make it.
How did you bring the art style of the Nikki series to an open-world adventure game?
Xie:
We aimed to present players with a warm, beautiful, and fantastical world filled with whimsical ideas.
The art style underwent numerous trials and validations by both the art team and technical artists (TA). The producer wanted to find the right balance between cartoon fantasy and realism. The lighting model in Unreal Engine is derived from Disney's PBR (physically based rendering) model, so despite the high proportion of cartoon elements, our lighting calculations follow PBR standards. This enabled us to give our models unique styles with realistic texture.
Our artists provided various references, and the TA implemented specific effects to closely match these references. We held weekly art benchmark meetings to align ourselves on the style of art and set a unified tone for the overall art direction.
The project initially started development on UE4 but quickly upgraded to UE5. How did that process unfold?
Xie:
The project began with UE4.23 and later upgraded to UE4.25 as we followed the main version updates. When UE5 was first released, we were hesitant to upgrade, considering the move premature as no games had been made and released using UE5 at that time. However, after evaluating it, we unanimously agreed that UE5 offers superior lighting quality. With numerous engine optimizations, it's very artist friendly and has greatly enhanced lighting efficiency. Thus, we planned to give it a try. Coincidentally, two weeks later, Epic announced its new version of Fortnite using UE5, which was a strong endorsement for the engine and solidified our resolve to upgrade to 5.0.
The upgrade was challenging and required extensive modifications to our engine, sparking internal debates about the risks and rewards. Ultimately, the producer made the final decision, convinced that the upgrade was significant, particularly for artistic convenience and performance improvements. Given that we have several other projects using Unreal Engine, this upgrade would benefit them as well. It became a strategic technical decision for the company. The producer emphasized that while using UE4 would still be competitive in May 2023, it would be outdated by the time Infinity Nikki launched. Therefore, upgrading to UE5, despite numerous challenges, was essential to our company. We all believed that we could overcome the upcoming challenges.
While we encountered issues during the upgrade process, we eventually completed the transition. This was just the first step; the second step involved getting feedback from two groups of designers and artists through two rounds of closed evaluations (CE). The tech team provided a rigorous comparison between UE5 and UE4 in the same environment. After evaluating memory, CPU, GPU, package size, and workflow, we all came into an agreement that UE5 was superior in all aspects.
The initial steps were done on a separate branch, avoiding any impact on the master project. The final step was merging with the master branch. In this process, data uploading was not allowed, but the developers could still work. It was quite a smooth transition. I would like to take this opportunity to thank the producer for his trust in us!
Xie:
The project began with UE4.23 and later upgraded to UE4.25 as we followed the main version updates. When UE5 was first released, we were hesitant to upgrade, considering the move premature as no games had been made and released using UE5 at that time. However, after evaluating it, we unanimously agreed that UE5 offers superior lighting quality. With numerous engine optimizations, it's very artist friendly and has greatly enhanced lighting efficiency. Thus, we planned to give it a try. Coincidentally, two weeks later, Epic announced its new version of Fortnite using UE5, which was a strong endorsement for the engine and solidified our resolve to upgrade to 5.0.
The upgrade was challenging and required extensive modifications to our engine, sparking internal debates about the risks and rewards. Ultimately, the producer made the final decision, convinced that the upgrade was significant, particularly for artistic convenience and performance improvements. Given that we have several other projects using Unreal Engine, this upgrade would benefit them as well. It became a strategic technical decision for the company. The producer emphasized that while using UE4 would still be competitive in May 2023, it would be outdated by the time Infinity Nikki launched. Therefore, upgrading to UE5, despite numerous challenges, was essential to our company. We all believed that we could overcome the upcoming challenges.
While we encountered issues during the upgrade process, we eventually completed the transition. This was just the first step; the second step involved getting feedback from two groups of designers and artists through two rounds of closed evaluations (CE). The tech team provided a rigorous comparison between UE5 and UE4 in the same environment. After evaluating memory, CPU, GPU, package size, and workflow, we all came into an agreement that UE5 was superior in all aspects.
The initial steps were done on a separate branch, avoiding any impact on the master project. The final step was merging with the master branch. In this process, data uploading was not allowed, but the developers could still work. It was quite a smooth transition. I would like to take this opportunity to thank the producer for his trust in us!
Dress-up has always been the core of the Nikki series. How is this aspect different in Infinity Nikki compared to previous games?
Xie:
The biggest difference in Infinity Nikki is that we've taken Nikki out of her display window and brought her into a vast, imaginative world, embarking on an adventure to collect lovely wonders. In this new world, every detail of Miraland comes to life, giving players a fresh perspective on the dress-up gameplay.
Overall, in Infinity Nikki, we aim to provide an unprecedented experience where the open world and dress-up gameplay are not only integrated, but also bring Nikki's story to life like never before. Players will delve into the narratives and cultural elements behind the different outfits as they explore and enjoy the game.
1. Integration with world exploration:
Nikki's key abilities in the open world, such as floating, purifying, cleaning, and bug catching, are linked to her outfits. Players will collect materials, craft Ability Outfits, solve puzzles, obtain higher-grade materials, and then create new Ability Outfits. In this way, their journey of exploring this open world is seamlessly integrated with dress-up elements in a continuous cycle.
2. Immersive dress-up experience:
To enhance the immersion of open-world dress-up, we focused extensively on the design of clothing, sound effects, and visual representations. For instance, the Bubbly Voyage floating outfit incorporates bubble elements that mimic the lightness of jellyfish.
In terms of sound design, when Nikki moves or uses her abilities, different outfits, shoes, accessories, and backpacks interact with the environment, producing unique sounds depending on the terrain. For example, high heels and flats will make different footstep sounds on grass, cement, or tiles. We've also added more details in Nikki's actions. When Nikki runs through the open world wearing her dress, she lifts the hem of her skirt. Moreover, the outfits will also display different effects based on the changes in lighting throughout the day and night.
Xie:
The biggest difference in Infinity Nikki is that we've taken Nikki out of her display window and brought her into a vast, imaginative world, embarking on an adventure to collect lovely wonders. In this new world, every detail of Miraland comes to life, giving players a fresh perspective on the dress-up gameplay.
Overall, in Infinity Nikki, we aim to provide an unprecedented experience where the open world and dress-up gameplay are not only integrated, but also bring Nikki's story to life like never before. Players will delve into the narratives and cultural elements behind the different outfits as they explore and enjoy the game.
1. Integration with world exploration:
Nikki's key abilities in the open world, such as floating, purifying, cleaning, and bug catching, are linked to her outfits. Players will collect materials, craft Ability Outfits, solve puzzles, obtain higher-grade materials, and then create new Ability Outfits. In this way, their journey of exploring this open world is seamlessly integrated with dress-up elements in a continuous cycle.
2. Immersive dress-up experience:
To enhance the immersion of open-world dress-up, we focused extensively on the design of clothing, sound effects, and visual representations. For instance, the Bubbly Voyage floating outfit incorporates bubble elements that mimic the lightness of jellyfish.
In terms of sound design, when Nikki moves or uses her abilities, different outfits, shoes, accessories, and backpacks interact with the environment, producing unique sounds depending on the terrain. For example, high heels and flats will make different footstep sounds on grass, cement, or tiles. We've also added more details in Nikki's actions. When Nikki runs through the open world wearing her dress, she lifts the hem of her skirt. Moreover, the outfits will also display different effects based on the changes in lighting throughout the day and night.
Can you explain the technical process for creating cloth and the engine features used? What challenges did you encounter in achieving the static and dynamic effects for different cloth designs and textures?
Xie:
In UE5, the cloth creation workflow is integrated directly within the engine, enabling us to create cloth, paint weights, and adjust properties in real time, significantly improving production efficiency. This is a major upgrade from UE4, where the process involved cumbersome exporting and importing data from DCC software.
In Infinity Nikki, as Nikki steps into an expansive world, we needed higher standards for both aesthetic and material effects, posing significant challenges for both the art and tech teams.
Our primary challenge is developing a versatile master material that could achieve various fabric effects while being easy for artists to use. This material needs to merge multiple fabric textures efficiently, reduce material variants, and perform well across different platforms. To achieve this, the tech team needs to keep optimizing visual effects and performance.
Another challenge is the semi-transparent elements of the outfits. Nikki's outfits feature many semi-transparent elements, like the Fairytale Swan outfit we see in the test composed of various sheer fabrics and silks. To handle transparency sorting issues, the tech team redeveloped Order-Independent Transparency (OIT), which perfectly resolved these challenges.
Xie:
In UE5, the cloth creation workflow is integrated directly within the engine, enabling us to create cloth, paint weights, and adjust properties in real time, significantly improving production efficiency. This is a major upgrade from UE4, where the process involved cumbersome exporting and importing data from DCC software.
In Infinity Nikki, as Nikki steps into an expansive world, we needed higher standards for both aesthetic and material effects, posing significant challenges for both the art and tech teams.
Our primary challenge is developing a versatile master material that could achieve various fabric effects while being easy for artists to use. This material needs to merge multiple fabric textures efficiently, reduce material variants, and perform well across different platforms. To achieve this, the tech team needs to keep optimizing visual effects and performance.
Another challenge is the semi-transparent elements of the outfits. Nikki's outfits feature many semi-transparent elements, like the Fairytale Swan outfit we see in the test composed of various sheer fabrics and silks. To handle transparency sorting issues, the tech team redeveloped Order-Independent Transparency (OIT), which perfectly resolved these challenges.
Creating dynamic and realistic cloth movements for the diverse outfit styles was another major challenge. We categorized cloth textures and applied a combination of skeletal physics and ChaosCloth simulations. For instance, outfits with crinolines, which are less flexible than regular fabrics, still require realistic physical dynamics. This solution balanced the effects with performance and ensured consistency across platforms.
Can you share your experiences or techniques regarding the construction and implementation of open terrains?
Xie:
For constructing and implementing open terrains, we employed several optimization strategies to enhance Virtual Heightfield Mesh (VHM) and Virtual Texturing (VT). Similar to tessellation, VHM allows for highly detailed terrain but can generate an excessive number of triangles. We used finer clustering techniques to cull a significant portion of the terrain triangles, optimizing performance.
As for VT, we utilized the ASTC format on mobile devices, which offers higher quality than ETC2. However, this required the GPU to compress RVT into ASTC at runtime, a challenging task we successfully tackled. The final ASTC VT quality closely matches the uncompressed quality, and we could draw decals and roads onto the VT seamlessly.
Xie:
For constructing and implementing open terrains, we employed several optimization strategies to enhance Virtual Heightfield Mesh (VHM) and Virtual Texturing (VT). Similar to tessellation, VHM allows for highly detailed terrain but can generate an excessive number of triangles. We used finer clustering techniques to cull a significant portion of the terrain triangles, optimizing performance.
As for VT, we utilized the ASTC format on mobile devices, which offers higher quality than ETC2. However, this required the GPU to compress RVT into ASTC at runtime, a challenging task we successfully tackled. The final ASTC VT quality closely matches the uncompressed quality, and we could draw decals and roads onto the VT seamlessly.
Can you explain the lighting implementation for characters and scenes in the game? What challenges did you encounter?
Xie:
We are committed to creating a beautiful world both in terms of characters and scenes, which demands high standards for lighting implementation.
For character lighting, we developed high-quality shadows specifically for characters to achieve detailed self-shadowing. Unique Global Illumination (GI) adjustments were made to enhance the lighting of dark areas on characters, and spotlights were integrated to support shadows for transparent parts of the characters, effectively managing differences and light leakage issues between transparent and opaque sections.
Xie:
We are committed to creating a beautiful world both in terms of characters and scenes, which demands high standards for lighting implementation.
For character lighting, we developed high-quality shadows specifically for characters to achieve detailed self-shadowing. Unique Global Illumination (GI) adjustments were made to enhance the lighting of dark areas on characters, and spotlights were integrated to support shadows for transparent parts of the characters, effectively managing differences and light leakage issues between transparent and opaque sections.
In terms of scene lighting, our technical and art teams collaboratively developed a tone mapping effect to establish the unique artistic style of Nikki's expansive world. GI parameter adjustments and modifications in occlusion and GI tracking were made to maintain the image's integrity while ensuring distinctive GI features, thus achieving the game's unique visual style.
Also, we're very cautious about post-processing and color grading, relying on natural lighting and fog effects to create the scene's atmosphere to leave room for photo filters and subsequent stylized scene effects.
Also, we're very cautious about post-processing and color grading, relying on natural lighting and fog effects to create the scene's atmosphere to leave room for photo filters and subsequent stylized scene effects.
Many of Nikki's gowns feature highly reflective accessories. What techniques did you use to achieve better texture and detail?
Xie:
To showcase the beauty of these accessories, we specifically developed a jewelry material to display high-reflection effects. This material, although opaque, utilizes Cubemap and other algorithms to achieve the unique refraction, reflection, subsurface scattering (3S), and various highlights of jewelry materials. This approach enhances the luster, delicacy, and visual depth of the accessories, making them appear more realistic and glamorous.
Xie:
To showcase the beauty of these accessories, we specifically developed a jewelry material to display high-reflection effects. This material, although opaque, utilizes Cubemap and other algorithms to achieve the unique refraction, reflection, subsurface scattering (3S), and various highlights of jewelry materials. This approach enhances the luster, delicacy, and visual depth of the accessories, making them appear more realistic and glamorous.
How do you ensure that different outfits and materials maintain consistency in a dynamic real-time lighting environment and changing weather conditions in UE5?
Xie:
For scenes with dynamic lighting changes, we adhere to standardized PBR inputs for materials, reducing complications during rendering. Despite this, we faced numerous adjustments due to artistic choices, particularly with semi-transparency under Lumen, which does not render in the same way as opaque materials. By using modified ambient boxes to adjust various scaling parameters, we were able to fine-tune the artistic look and address semi-transparent rendering issues, achieving high visual credibility and consistent style.
Xie:
For scenes with dynamic lighting changes, we adhere to standardized PBR inputs for materials, reducing complications during rendering. Despite this, we faced numerous adjustments due to artistic choices, particularly with semi-transparency under Lumen, which does not render in the same way as opaque materials. By using modified ambient boxes to adjust various scaling parameters, we were able to fine-tune the artistic look and address semi-transparent rendering issues, achieving high visual credibility and consistent style.
Are the numerous magical effects in the game developed using Niagara?
Xie:
Yes, Niagara's particle-by-particle programming capabilities and inter-particle communication make effects more flexible and dynamic compared to the previous effect editor. By leveraging Niagara's programmability, we created numerous modules to optimize performance and enhance visual effects. Additionally, we rebuilt the particle collision system from the ground up.
Using Niagara, we enabled interactions between characters and particles, such as leaves being affected by the airflow from Nikki’s footsteps. We also animated coiled tails on game animals in a lively and flexible manner according to artistic designs, which would have been impossible with traditional particles.
Xie:
Yes, Niagara's particle-by-particle programming capabilities and inter-particle communication make effects more flexible and dynamic compared to the previous effect editor. By leveraging Niagara's programmability, we created numerous modules to optimize performance and enhance visual effects. Additionally, we rebuilt the particle collision system from the ground up.
Using Niagara, we enabled interactions between characters and particles, such as leaves being affected by the airflow from Nikki’s footsteps. We also animated coiled tails on game animals in a lively and flexible manner according to artistic designs, which would have been impossible with traditional particles.
Can you explain the technical applications for physics simulations in the game, such as floating, gravity, and balance effects for paper cranes in the scenes?
Xie:
During the exploration of the open world, we included many interactive objects, such as flags in the wind, bottles by the roadside, and breakable boxes. Simple interactions are implemented using World Position Offset (WPO), while more precision-demanding interactions are calculated using the Chaos system.We stayed within the given budget by optimizing assets and adjusting algorithms. This enabled real-time interactions with objects, providing a gameplay experience that feels very realistic.
Xie:
During the exploration of the open world, we included many interactive objects, such as flags in the wind, bottles by the roadside, and breakable boxes. Simple interactions are implemented using World Position Offset (WPO), while more precision-demanding interactions are calculated using the Chaos system.We stayed within the given budget by optimizing assets and adjusting algorithms. This enabled real-time interactions with objects, providing a gameplay experience that feels very realistic.
Has the team developed additional features to meet specific game requirements?
Xie:
Yes, we have developed several new features to achieve special effects in the game:
Xie:
Yes, we have developed several new features to achieve special effects in the game:
1. Fur technology:
The fur on Nikki's outfits and all animals is created using a proprietary ShellFur-based system developed by our engine team. It is compatible with PC, console, and mobile platforms, enabling artists to edit fur directions in the editor using splines. At runtime, each fur layer is dynamically rendered as instances. The benefit of instance rendering is that we can adjust the number of fur layers in real time based on the object's screen size, and thus optimize performance.
The fur on Nikki's outfits and all animals is created using a proprietary ShellFur-based system developed by our engine team. It is compatible with PC, console, and mobile platforms, enabling artists to edit fur directions in the editor using splines. At runtime, each fur layer is dynamically rendered as instances. The benefit of instance rendering is that we can adjust the number of fur layers in real time based on the object's screen size, and thus optimize performance.
2. GPU-driven technology:
To handle the complex open world and vegetation rendering, we developed a GPU-driven rendering solution suitable for PC, console, and mobile platforms. This system utilizes the GPU's parallel processing capabilities to handle instance culling and level of detail (LOD) calculations. Our original method combines ComputeShader and rasterization culling to accurately occlude each instance, followed by DrawIndirect and MultiDrawIndirect for batch rendering. Additionally, GPU feedback results are sent back to the CPU to further cull draw calls and stream mesh LODs, enabling the rendering of millions of vegetation instances on screen in Infinity Nikki.
To handle the complex open world and vegetation rendering, we developed a GPU-driven rendering solution suitable for PC, console, and mobile platforms. This system utilizes the GPU's parallel processing capabilities to handle instance culling and level of detail (LOD) calculations. Our original method combines ComputeShader and rasterization culling to accurately occlude each instance, followed by DrawIndirect and MultiDrawIndirect for batch rendering. Additionally, GPU feedback results are sent back to the CPU to further cull draw calls and stream mesh LODs, enabling the rendering of millions of vegetation instances on screen in Infinity Nikki.
3. Skeletal chain technology:
Collision handling is a significant challenge in cloth simulation, especially with large movements and high-performance requirements. Our proprietary skeletal chain algorithm and improved cloth algorithms replace time-consuming and unstable traditional collision methods with a stable and controllable constraint algorithm.
For example, during pre-processing, we add flexible and soft driving constraints to prevent severe clipping between cloth and body during large movements. During cloth solving, our rigid collision constraint algorithm strictly prevents clipping, even at high relative speeds. We also implemented multi-layer cloth collisions. These algorithms enable high-quality cloth collision effects during rapid movements while maintaining low computational costs.
Collision handling is a significant challenge in cloth simulation, especially with large movements and high-performance requirements. Our proprietary skeletal chain algorithm and improved cloth algorithms replace time-consuming and unstable traditional collision methods with a stable and controllable constraint algorithm.
For example, during pre-processing, we add flexible and soft driving constraints to prevent severe clipping between cloth and body during large movements. During cloth solving, our rigid collision constraint algorithm strictly prevents clipping, even at high relative speeds. We also implemented multi-layer cloth collisions. These algorithms enable high-quality cloth collision effects during rapid movements while maintaining low computational costs.
4. Real-time clipping technology (dressing room combination):
Combining different outfits often leads to unavoidable model clipping. We developed a proprietary geometric algorithm to address real-time clipping issues. This algorithm detects the interpenetration relationships between all parts of the character's body and deforms or hides the affected areas according to set rules.
We also support custom handling rules, such as rigid body changes and following, mesh smoothing, and area linkage processing. Given the computational intensity of intersection detection, which increases with model complexity, we use a pre-computation system to store time-consuming calculation data, reducing runtime computational load. This ensures smooth performance during outfit changes, solving issues like hair and hat clipping, outerwear and shirt visibility, and waist adjustments for pants and shirts.
Combining different outfits often leads to unavoidable model clipping. We developed a proprietary geometric algorithm to address real-time clipping issues. This algorithm detects the interpenetration relationships between all parts of the character's body and deforms or hides the affected areas according to set rules.
We also support custom handling rules, such as rigid body changes and following, mesh smoothing, and area linkage processing. Given the computational intensity of intersection detection, which increases with model complexity, we use a pre-computation system to store time-consuming calculation data, reducing runtime computational load. This ensures smooth performance during outfit changes, solving issues like hair and hat clipping, outerwear and shirt visibility, and waist adjustments for pants and shirts.
In addition to these technological advancements, we continually strive to enhance the realism and immersion of the open world, ensuring players can enjoy the rich experiences brought by these technical upgrades.
The design and user experience of Momo’s Camera are very interesting. How did you use UE5 to create this camera?
Xie:
During the open-world adventure, players can use Momo's Camera at any time to capture memories of their journey. We aimed to provide players with a comfortable, convenient, and powerful photo system.
For camera controls, we utilized various UE Camera features to simulate real camera behavior. Adjustments like aperture and focus distance enable players to control the depth of field effects. Focal length adjustments let players change the image size and distortion. Rotating the lens gives players the ability to take unconventional photos.
Xie:
During the open-world adventure, players can use Momo's Camera at any time to capture memories of their journey. We aimed to provide players with a comfortable, convenient, and powerful photo system.
For camera controls, we utilized various UE Camera features to simulate real camera behavior. Adjustments like aperture and focus distance enable players to control the depth of field effects. Focal length adjustments let players change the image size and distortion. Rotating the lens gives players the ability to take unconventional photos.
In terms of photo effects, we leveraged UE's native post-processing effects, such as vignetting, to enhance the photo's atmosphere. Various filters were also added during the post-processing stage to add color and flair to the photos.
Additionally, when Momo takes photos of Nikki, players can choose from a variety of poses for Nikki and let her look directly at the camera through detailed options. We used a combination of UE animation features like Aim Offset, Control Rig, and Blend Space, and customized some nodes to enhance the fluidity and expressiveness of Nikki's poses.
Additionally, when Momo takes photos of Nikki, players can choose from a variety of poses for Nikki and let her look directly at the camera through detailed options. We used a combination of UE animation features like Aim Offset, Control Rig, and Blend Space, and customized some nodes to enhance the fluidity and expressiveness of Nikki's poses.
Thank you for the interview—we’re very excited about this game. Can you recommend official channels to stay updated with the latest news?
Xie:
We are grateful to be interviewed as well!
Please visit our official website and YouTube channel to learn more about Infinity Nikki.
Xie:
We are grateful to be interviewed as well!
Please visit our official website and YouTube channel to learn more about Infinity Nikki.
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