What is foveated rendering, and why can it make PSVR 2 streams blurry?

thesixthaxis.com:

Pushing high-end graphics in virtual reality is a demanding endeavour for any VR headset processor, whether it’s a standalone headset, a high-end PC or the PS5 and PSVR 2. It’s made harder still for PSVR 2 by the high-end specs of the headset and the new expectation for high resolution gaming. So, how does the PS5 pull it off, and why doesn’t it always translate to what you can see in YouTube and Twitch streams?

One of the tricks that PSVR 2 leans upon when render virtual reality is called foveated rendering. You’ll see this term used in a lot of bullet point lists when games are being upgraded or ported to PSVR 2, alongside noting support for 4K and HDR. It’s a lot of attention for a rather technical feature to get, but what is it?

To put it simply, foveated rendering is a way to reduce image quality for parts of the screen that are in your peripheral vision. The game can prioritise where it’s spending the most hardware resources to get the best performance and visual effect for the player.

Focusing on the target with my bow, Horizon Call of the Mountain uses foveated rendering to lower the resolution elsewhere, most noticeable on the blurrier barrels and settlement in the top left.

It’s all based on real life. When you focus your vision on a cup on a coffee table, for example, the rest of the room that is outside that central focal point is less clear to your eyes and brain. Foveated rendering simulates that effect in VR, allowing the game engine to reducing detail and resolution in places that you aren’t looking.

This has been used since the very start of the current era of virtual reality gaming in 2016, but was initially done in a more rudimentary fashion by locking the focus point to the direction of the headset. Some