Wild guess discussion on Apple GPU ray tracing

[Danny82]

let's talk Apple silicon with ray tracing

Ray tracing has been the hype of RTX range, AMD and new console will focus on. As much as I dream Apple GPU will be around RTX 2060 super desktop class raw performance, has been kick out of my dream in my other realistic expectation thread..

Would love to hear u guys discuss on Apple silicon with ray tracing like is it even possible if Apple GPU has only raw performance of gtx 1650 or even 1660 to be able to also produce good amount of ray tracing..? I don't know the technical aspect of a GPU but is ray tracing a separate formula towards raw GPU performance or it has to go hand in hand..?

And if u do think Apple silicon will one day implement ray tracing into their GPU, which generation Apple Silicon would be your guess (guessing just for fun)..? My discuss will be 2nd gen Apple silicon as seeing Apple licenced Imagination.. I know everyone is saying Apple GPU is totally different from Imagination GPU and they just licence maybe for patent purpose.. but seeing that they are able to licence it, I believe they would also know Imagination formula to put Ray Tracing into their GPU for mobile.. and seeing that Imagination claim that they next series of GPU (maybe B series) to be completed end of this year with hardware base ray tracing, I guess Apple could use their formula and work their magic towards bringing it to us.

Just so to be clear, am talking about Apple GPU for macbook to have ray tracing

Happy discussion everyone.

 

[NotTooLate]

Its already there since last year , they even expand on it this year.
https://developer.apple.com/videos/play/wwdc2020/10012/

 

[psingh01]

Ray tracing is not a new invention, but it’s always been very slow. Something you would spend a long time in rendering each frame of a movie, but once that is done you can just play the movie and see the results.

The video above talks about the API to do ray tracing. Meaning the programmer can use that rather than work out all the algorithms themselves. Parts of it are accelerated by the GPU, but at least from the demo shown it was not real time (what you need for games). Nvidia is supposed to have specialized hardware within the gpu just for ray tracing which speeds things up fast enough for games. Now it’s possible that the scene they chose was overly complex so it rendered slowly, but I have to imagine if they could do something good in real-time then they would have shown that off.

I wouldn’t expect Apple to be able to compete with nvidia in this arena just yet. However, when their hardware gets to that level, people using these APIs will see the benefits.

 

[jinnyman]

Ray tracing at high resolution requires a lot of raw power.
Unless Apple can show us any concrete roadmap in high performance(I mean those that requires 250w power) gpu development, I doubt what Apple can offer can match nVidia.
Unlike Intel, nVidia is the king in that sector.

For low performing, I think what's in A12z is more than enough. Considering optimum scalability starting from A12z gpu and what would be A14 graphic, I think it's ok to assume up to 2060 super performance level. After that, SoC combined with shared bandwidth memory structure pretty much limit going above that.

As of now, i don't see Apple can achieve 2080ti level, or upcoming 3080ti, 3090 level of performance utilizing SoC with shared memory. That nVidia card alone consumes tons of power. As much as I admire Apple's ability in chip development, they are not magicians. 5nm SoC delivering nVidia 7~8nm(7nm TSMC vs 8nm Samsung) standalone gpu performance? no way.

 

[leman]

As mentioned previously, Apple already has ray tracing support in Metal and this year they have radically improved it. From a quick glance I’d say that they now have feature parity with DX12 or might be even a bit ahead of it (Apple offers dynamic linking for custom intersection functions which I don’t think DX1w has).

Currently all this seems to runs in “software” on the GPU and the performance is “meh”. Apple tech demos are so far geared towards pro apps that want to do content creation via ray tracing. It can be used in games for other purposes however, like path finding etc.

Anyway, from the shape of the API, Apple certainly left a path forward to have hardware accelerated RT. I think we will see it some time soon. I tend to agree with @jinnyman that they are unlikely to outperform Nvidia here - Apple GPUs are inherently much more efficient than big GPUs due to how they draw stuff, but this doesn’t really carry over to RT. I can imagine them doing some tricks though, like overlaying RT hardware with the ML accelerators.