The power of ray tracing
It’s not yet another Madonna comeback; these rays of light impress
PS5 promises to bring the realistic light show of cinema CG to next-gen games with the inclusion of hardware-based ray tracing. We’ve heard a lot about this visual wizardry over the past 18 months, and even recently experienced it in a limited way with Crysis Remastered’s software-based approach.
But what is it, and why should you care? Put simply, ray tracing is a method of simulating realistic light in real time. It maps the path of light particles as they interact and bounce off and pass through objects in a scene. This means the light has a volume and exists in a space, ensuring reflections and shadows are all accurate.
In current-gen games light is fixed. It acts as a rigid block that can be made to look realistic in the hands of talented developers, particularly in fixed and controllable spaces like those you find in games such as The Last Of Us Part II, but it’s not real. A ray of light shining through trees on Ellie’s journey through Seattle is pre-set and predictable; using a technique known as rasterization it mimics how light can affect an object.
In a PS5 game such as Marvel’s Spider-Man: Miles Morales, where light is ‘traced’, it fills the space, the world, and reacts realistically to characters entering a scene. Light is now a dynamic, interactive ‘shape’ that alters naturally. A beam of light is no longer a direct single source but is bouncing all over the scene.
Ray tracing’s usually used in pre-rendered film CG; PS5’s use of it is edging games closer to their computer-generated big-screen counterparts. As such it can sap power from the console, so we may see ray-traced enabled games settling on 30fps or using ray tracing in specific moments or levels to heighten an experience, such as boss fights.
The race for polygons is over and in its place we have a chase for a new way to simulate light. It’s something you need to see in action. It gives game spaces depth and subtlety. In the remastered Marvel’s Spider-Man we see our web-head reflected in the gleaming windows of skyscrapers and the car doors as he swings through New York at street level. The world feels as if it’s a reactive, living space; there’s a warmth to the glow from Times Square’s billboards.
As the PS4 era winds down we’ve been spoilt for beautiful looking games: TLOU2, God Of War, Days Gone, Call Of Duty, and Control have all pushed this PlayStation generation to new visual heights. Ray tracing will ensure future games on PS5 not only look real, they real.