Ray tracing in smartphones and PCs
Ray tracing is a method of rendering 3D graphics that calculates the path of light rays: how they bounce, bend and create shadows. Hardware ray tracing means the GPU has dedicated blocks for this.
In plain words
Regular game graphics are like theatre scenery: shadows are painted in advance and reflections are faked. Ray tracing is like real light on a film set: shadows and highlights appear by themselves because the path of every ray is calculated. It looks realistic, but it is very hard to compute.
How it works
- Rays are "cast" into the scene from the player's camera.
- For each ray, the system calculates what it hit and where it bounced.
- This determines the pixel's colour, taking light, shadows and reflections into account.
- Dedicated GPU blocks speed up finding where rays meet objects.
- To keep frame rates up, games often combine ray tracing with regular graphics and AI upscaling.
Where you'll see it
In PC graphics cards and consoles, and in recent years in flagship smartphone and tablet chips. Manufacturers mention "hardware ray tracing" in GPU descriptions. There are still few mobile games that support it.
Does it matter when buying
For most people on a phone, no: there are few ray-traced games, and it heats the device quickly. For a PC gamer, yes - it noticeably improves the image in modern games. I would not pay extra for a smartphone just for ray tracing.
Myths
- Myth: Ray tracing always makes a game better. Reality: It makes lighting more realistic but lowers the frame rate and increases heat.
- Myth: Ray tracing is a recent invention. Reality: The method has been used in film for decades; what is new is doing it in real time.
FAQ
Do iPhone and Android phones have ray tracing?
The latest generations of flagship chips have hardware support.
Can I turn off ray tracing in a game?
Yes, usually in the graphics settings.
What are DLSS and similar technologies?
AI upscaling: the game renders at a lower resolution, and a neural network "fills in" the details.
Related terms
Graphics processor (GPU), Thermal throttling, System on a Chip (SoC)