Working With Epic to Debut The Witcher 4 Unreal Engine 5 Tech Demo at Unreal Fest

We’ve been creating games for more than 20 years but have never done anything like this, making it an exciting and challenging time for us. But we wanted to share the tech we’ve been creating with Epic Games — and how we’re using each tool to create the most immersive Witcher game to date.

These aren’t just for show either — each of the five highlighted during the tech demo will be available to all Unreal Engine 5 developers. We hope that, with other creators incorporating these tools into their games, the entire industry will be pushed forward and a new class of open-world games created.

“We're collaborating with Epic Games to develop The Witcher 4 using Unreal Engine 5 because we want to push open-world game design further, not just for our benefit but for the entire industry,” said Sebastian Kalemba, Game Director of The Witcher 4.

“By creating and sharing innovative technologies like FastGeo Streaming and Nanite Foliage, we're working to build more immersive and realistic game worlds. We love contributing to the broader game development community and aim to set new standards that inspire and benefit other developers.”

These tools mentioned by Kalemba — FastGeo Streaming and Nanite Foliage — are two of the five we showcased in the tech demo, alongside Mass System, ML Deformer, and Unreal Animation Framework, and each one contributes to us creating the most immersive Witcher game to date.

FastGeo Streaming, for example, allows everything in Kovir — a never-before-seen region debuted in the tech demo and confirmed for The Witcher 4 — to seamlessly load without visual hiccups or performance compromises. Dense forests, snowy mountains, and bustling trading hubs like Valdrest are all loaded quickly using a lightweight method that lets players breathe it in without immersion being broken.

We’re focusing on the small-scale too, of course, evidenced by the likes of Nanite Foliage. Essentially throwing out past industry standards, this new technology allows us to create dense and detailed environments like the forests around Valdrest without performance taking a hit. We’re truly paying attention to every detail, from the world at large to individual leaves on lush plants.

“Our goal with The Witcher 4 is have art and tech come together to raise the bar of what an open-world game can be,” said Jan Hermanowicz, our Engineering Production Manager. “I'm super happy that we found a partner that shares this ambition. Working to advance Unreal Engine 5 with Epic is giving our developers the tools they need to bring their ambitious artistic visions to life.”

Just to keep us on our toes, we also threw in the extra layer of playing The Witcher 4 Unreal Engine 5 Tech Demo live on stage in front of more than 2,500 people in person and more than one million more watching online. This was definitely the riskier approach, compared to sharing a pre-recorded clip, for example, but we felt confident in the tech demo and, above that, super excited to share it!

“We played the demo live on stage because we wanted to show that we’re creating real technology with Epic,” said Kajetan Kapuściński, our Cinematic Director and also the RED who went on stage with a controller in hand.

“What we’re creating is ambitious and complex but it’s also real technology that works right now on current generation hardware. We chose to show it without smoke and mirrors because we didn’t need them. As a CD PROJEKT RED employee who believes wholeheartedly in this tech demo, I felt very confident. But I also felt a lot of pressure to show off the amazing work my colleagues had been working on! It was a tense but ultimately incredible experience.”

Though our tech demo wasn’t gameplay of The Witcher 4 itself — but instead a showcase of some of the technology being used to create it — we were so happy to share it with the video game community at Unreal Fest alongside a series of talks going deep into the tech involved.

Our Engineer, Animation, Adrianna Bielak, who led a segment called Bringing Kovir to Life with UAF as part of a larger talk on Unreal Animation Framework, said the chance to discuss the tech demo at Unreal Fest was a highlight of her career. “I felt I was part of something groundbreaking, not only for the company but for the industry as a whole,” she said.

Though this could have added pressure to Adrianna’s talk, which she gave a day after the tech demo’s reveal, she said it only added more motivation. “I was keen to ensure that the way I presented the tech demo content in my talk was of an equally high standard and provided the audience with both inspiration and an understanding of that part of the project,” Adrianna said. “The interest and curiosity of the attendees grew by the hour, which I felt through the questions we were asked between sessions and the congratulations we received.”

Other REDs led talks at Unreal Fest too: Expert Engineer, Core Jarosław Rudzki on Streaming Improvements for Dense Worlds and Road to 60FPS in The Witcher 4 Unreal Engine 5 Tech Demo, Senior Technical Animator - Coordinator Julius Girbig on Locomotion and Interactions for Hundreds of Characters, and Senior Cinematic Designer - Coordinator Rafał Kruk on Cinematic Transitions and Scalable Timelines.

The entire event was incredible, headlined by the reveal of The Witcher 4 Unreal Engine 5 Tech Demo, and we’re so proud of all the REDs involved in making it happen! But for now we’re locking back in and getting back to work on making The Witcher 4 the most immersive Witcher game to date.