A three-year journey transforms CORYS’s 3D rendering capabilities and positions the company at the forefront of digital twin technology.
When CORYS made its first foray into the world of photorealistic computer-generated images in 2021, the stakes were high. The company had pioneered 3D computer-generated images, but its legacy 3D engine, discontinued in 2014, was no longer supported and relied on CORYS’s in-house maintenance efforts to keep it in operating condition.
“We went into the project with a technical debt related to our decades-old legacy solutions,” said CORYS VP Transportation Renaud Perez. “We were at risk of falling behind, and we needed a new direction.”
That new direction came in the form of Epic Games’ MegaGrants program. CORYS submitted its pitch and secured not just funding, but a technical and commercial partnership that would prove invaluable.
“Epic’s support was a decisive factor,” said Renaud. “Their source code is available on GitHub for anyone to use, but their solutions architects provided us with critical input that allowed us to make the right technology choices. In business terms, Epic Games is a much larger company than CORYS, and the opportunity to be promoted at their events and on their website was another clear benefit.”
CORYS’s position as a pioneer in high-fidelity 3D environment creation won over Epic Games’ judges. The company had spent years developing an innovative approach to 3D asset generation, using photogrammetry and scanning technology to capture real-world environments — including buildings, terrain, tracks, signs and signals — then extracting the data and using AI to populate highly detailed 3D spaces at ultra-high resolution.
“We can now reach down to 3 centimetres accuracy for all object positioning within the 3D database,” said Renaud.
New technology transforms CORYS’s organization and team
The project reinvigorated CORYS’s team, as well. A dedicated 30-person R&D department now combines veteran CORYS 3D technology specialists with young talent recruited specifically for this transition.
“Working on cutting-edge technology with a partner like Epic Games allows us to attract young talent,” said Renaud. “In addition to more traditional software engineers, we have had to hire new profiles like 3D technical artists and 3D level artists, many recruited from specialized schools in France and Canada.”
The new and improved R&D team at CORYS has exceeded expectations. Unreal Engine Solution Architect Director Alban Bergeret has been particularly impressed with CORYS’s ability to run with the new technology.
“There has been some fantastic work! CORYS is at the top of simulation developers working with Unreal Engine. The modelling tools and production pipeline they’ve developed are outstanding!”, he said.
Nicolas Bertea Senior Software Engineer in R&D (Unreal engine tools & AI Gameply Specialist).
“When we first started exploring Unreal Engine, I was both excited and sceptical about whether we could truly bring our ambitious ideas to life. But Unreal Engine completely transformed the way we work.”
Romain Larousse, Computer graphic designer, production tools designer, Lead Tech Art
“I am very proud of the work already accomplished by the development team. I believe this tool will likely be the most powerful for efficiently creating railway lines with a very high level of immersion.”
First major project milestones reached in 2025
The partnership hit two milestones in 2025. The first was at Epic Games’ UnrealFest in Orlando in June, where CORYS presented as a keynote speaker at the world’s largest 3D event. Nikola Jancovicova, Senior Business Development Manager at Epic Games, returned the favour with a presentation of Unreal Engine at SimTech in October. The second milestone was the first commercial deployment of CORYS simulators with Unreal environments in July 2025 at DB Cargo Netherlands. Jurgen Knops of DB Cargo NL praised the photorealistic environments in his presentation of the groundbreaking project at SimTech.
Renaud concluded, “Our goal is to bring a new level of realism in simulating the real world for the benefit of the transportation industry, working on main pillars: high resolution, photorealism, and our Production Pipeline & Edition tools for cost-effective simulation. The results we are getting working with Unreal Engine are amazing, and we are all very excited with the release of this new technology.”
From real-time 3D rendering to digital twins
CORYS’s vision extends far beyond driver training. The foundation created by the partnership with Epic Games and the real-time rendering capabilities of Unreal Engine have opened a path toward true digital twins — integrating high-fidelity simulation with asset management, incident analysis using downloaded train data, and validation of autonomous systems using synthetic sensor data. Currently in R&D at CORYS, these new solutions will be deployed next year, with the goal of providing comprehensive digital twins and engineering platforms.
“Training AI on synthetic data allows us to explore scenarios that would be difficult in real life,” said Renaud.
This positions CORYS at the intersection of enhanced driver training, route learning, and the engineering validation needed for autonomous railway systems.
In just three years of R&D, CORYS has transformed its technology and its organization and is now able to deliver next-generation simulation to its transport and mobility customers, expanding the possibilities of advanced simulation.
Link to the CORYS Unreal Fest keynote in Orlando
Link to the Unreal Engine blog
