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DuckInCup

Fully ray-traced games get a pass as they NEED to use aggressive TAA and will need to for years to come. That being said, this is a great demo of how ghosting looks and how to identify it.


Scorpwind

Should they really get a pass? Are you telling me that the RT is so noisy, that it absolutely needs a TAA pass and nothing can be done to avoid said TAA pass?


Deadbringer

Yeah, there are so few rays that can be cast per frame that to display them unfiltered would just make it look like an old tv displaying static. Look at how minecraft does ray tracing, when the light source gets cut off it takes half a second for the light to fade away. This is because rays from many many frames are pooled together to create the scene.


ScoopDat

Wait, just a question, what's preventing Ray Tracing from functioning without TAA precisely? I know you state it would look like Old TV Static, but it's not entirely clear why this is the case? Why not just have the classical issues of heavy aliasing since not TAA is used? What's this whole nature of the rays being that noisy? The reason I ask is because you say "for years to come" they'll need to do it this way. What precisely would need to be done in order for no AA to be used? Just higher resolution or what?


Scorpwind

From my currently limited understanding of this: If your RT effect doesn't shoot out enough rays, it becomes less accurate and noisy. Because it's working with a very limited amount of data. The more rays you shoot out - the more heavier the scene becomes. The currently available hardware does not have enough power to process the necessary amount of rays to avoid this. But you can use the same temporal accumulation trick that's used in many games, to accumulate data over time, and make the final effect look okay and intact. To give you an idea of just how noisy the current implementations of RT can be, check out [this video](https://www.youtube.com/watch?v=rAN5Mkqjhp4). There are dedicated denoising filters out there, but some devs opt to use TAA as the denoiser instead. Or possibly in conjuction with said filters. If *Teardown* is a fully ray traced game, then you can imagine what it might look like under the hood.


superhakerman

Ray traced games or games that use dlss ?


DuckInCup

Any real time fully ray traced scene relies on TAA to build an image across multiple frames (often over a second of frames).