Unreal Engine recently unveiled Unreal Engine 5, which includes many great new innovative features, one of which is the lumen.
If you’re familiar with, or even if you’re not, lumen, we’ll answer all of your questions and compare lumen to the industry’s next big thing, Ray Tracing, in short, Lumen vs RTX.
So, if you’re curious about the lumen, what difference it can make, and why we’re comparing it to the RTX, keep reading until the end.
What is Lumen?
By the definition from Unreal Engine, Lumen is Unreal Engine 5’s fully dynamic global illumination and reflection system that is designed for next-generation consoles, and it is the default global illumination and reflections system.
Lumen is the default global illumination and reflections system in Unreal Engine 5. It renders diffuse interreflection with infinite bounces and indirect specular reflections in large, detailed environments at scales ranging from millimeters to kilometers.
What is Ray Tracing?
Ray tracing, which has long been used for non-real-time rendering, provides realistic lighting by simulating the physical behavior of light. Ray tracing calculates the color of pixels by tracing the path that light would take if it were to travel from the eye of the viewer through the virtual 3D scene.
Simply described, ray tracing is a technology used in video games to make light behave how it does in real life. It works by mimicking genuine light beams, using an algorithm to track the path that a beam of light would take in the physical world.
Lumen vs Ray Tracing
Hardware Requirement
Lumen has an advantage in terms of hardware requirements because it does not require the same level of light calculation as ray tracing. This means that lumen can render realistic light but does not require ray tracing.
Winner: Lumen
Visuals
If you want to see the difference between lumen and ray tracing, Anderson Rohr has a wonderful video about lumen vs ray tracing that you should watch.
In terms of visuals, a direct answer is difficult to provide because the lumen has global illumination as well, but without the need for backing into the texture.
And on the other hand, RTX renders light on a realistic system, but that requires a pretty powerful GPU to pull that off.
But GPUs are also becoming much more powerful, so this means RTX does have a long-term future in gaming and lumen has the advantage of being much more smooth and pretty realistic without the need for powerful hardware.
Both lumen rendering and ray tracing can provide visually stunning effects. There are, however, some significant differences between the two approaches.
Ray tracing, on the other hand, generates light by “tracing” imaginary rays from your scene’s objects out into the virtual environment around them (hence the name). This produces more realistic lighting overall, but it also requires a strong GPU to render smoothly because more calculations are required. Finally, it’s up to you to decide which technique you prefer—both offer advantages and disadvantages in terms of visuals.
Winner: Draw
Conclusion
RTX and Lumen are both great technologies. RTX has been used for rendering non-realtime for a long time and, in very recent years, RTX has come to gaming, so there is still a lot of progress to make with RTX in gaming.
The Lumen is also a relatively new light technology, but it has several advantages.
For example, a lumen will be included in the Unreal Engine 5, which means that many future games that use UE 5 will have the option to use a lumen because it does not require a specific GPU to achieve realistic global illumination and, as a result, a lumen is not a resource-hungry illumination system.
But also, RTX is going nowhere here. We will still have many RTX games now, and in the future, but having more than one option for realistic global illumination for video games is a huge thing for gamers and developers.