Update: DX12 coming to PC soon --> (Old post: DX12 is NOT coming to PC on July 27. Xbox Will Get DX12 First, Then PC Later)

Yes indeed, stability is above everything. P3Dv5 until today has been like roller coaster because of DX12 and we don’t want MSFS to be like that

I don’t know how many users out there use fs2020 with a gpu not supporting dx12u in the same version Xbox does. I’m no expert at this topic. But they would be cut off.

And indeed DX12 allows for a totally different approach to supporting multi-threaded rendering like it is explained in this article:

Understanding DirectX* Multithreaded Rendering Performance by...

This is something I’m also wondering from an engineering perspective: in order to get the most of this multi-threaded rendering you might be forced to also review the entire rendering pipeline asset management, task-scheduler, sync points, draw call batching, etc… For example during the XP11.50 beta, the Vulkan API was only one part of the entire solution, but the other and non negligible part was also to entirely refactor huge chunks of the rendering pipeline architecture in order to suit the new paradigm better.

In other words, to what extent optimizing the renderer for DX11 API paradigm is preventing you from fully using DX12 potential and vice versa is a question, and I can’t wait to see this in action by the 27th.

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I believe you have a point here, and you are right the main reason could be as simple as this!

But if this is the case, this means there will be 2 rendering engines: DX12 Xbox with the game code optimized for DX12 multi-threading, and DX11 PC with the game code optimized for DX11 (looking at the intel article there is a clear advantage to using different approaches depending on the API). Maybe this is why Seb was saying we shouldn’t expect a lot more performance with DX12, rather more visual effects or similar things, although today’s Q&A is really convincing they are doing a great job (and if you pay attention to this, look also to the VRAM and SYSRAM figures between SU4 and SU5!!!)

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I am no expert on rendering but has some familiarity this topic

My understanding is that currently MSFS (SU4) is heavily handicapped by Draw Calls (and throughputs) in dense areas which put a lot of stress on CPU cycles. There are at least two ways to mitigate the problem

  1. Reducing number of draw calls by building the render pipeline more efficiently. I believe this is what they did for SU5 on DX11
  2. Increasing draw call throughputs per CPU cycle which I believe is what DX12 would bring to the table through better/more customized parallelization and batch

So I think it’s a win-win considering 1 & 2 are not mutually exclusive and as a matter of fact, if they did 2 first then they may not have the motivation to do 1 later. Now, they did 1 and will do 2 eventually, which makes me think the great visual potential from MSFS has yet to come

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These are very good points too, but considering they would have done both 1) and 2) just for the sake of the Xbox version, what is therefore the remaining road block for DX12 on PC… :slight_smile:

PS: this is just an engineering related question which I’m curious about when thinking about this.

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Haha yeah.

I am more worried about you actually - your wonderful performance guides (both flat screen and VR) may need a huge update after SU5 :laughing:

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Thank you for your kind words! I’ve indeed delayed updating these for months because of the upcoming SU5 and DX12. No point in changing them before :slight_smile:

Now the true metric of performance for me will be when I’ll be able to run the Reality XP GTN and GNS V2 update and rendering loop as fast in FS2020 than in XP11!*

*the upcoming RXP XP11 updates are about twice as fast:
on the same system the GTN/GNS update+render loop was around 150us, it is now 75us (micro seconds)… and the GNS for example rendering both in a popup window and the virtual cockpit at the same time is totaling about 100us (update + 2x renders) :slight_smile:

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Oh they probably have to downgrade more in the pc version to get it ready for their messed up Direct X 12 release for PC.

Now it will be interesting if the PC version gets left behind as the Xbox version gets more popular. I thought that all versions had to be the same!?!?! Apparently this isn’t the case anymore. So we beta test this mess for them at great expense of our own, and then they give all the candy to the console kids. Wow!

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There is no such thing as a free lunch. I hope that the performance updates don’t come at a cost, e.g. decreased visuals.

From what I’ve read though, it does sound very promising, though I’m really quite happy with what I’m getting at the moment TBH. Yeah, I get the odd stutter, but these seem a lot fewer and more far between than they were a couple of months back.

Looking forward to the forthcoming enhancements and hoping there will be no bugs.

watch today’s Q&A. The sims will be the same, this was stressed multiple times.

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you’re just begging for an argument… lol

And as mentioned prior to your comment, they stressed in today’s Q&A that neither platform is preferred and both will remain practically identical.

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It’s also worth noting – Xbox Series S will be locked at 30. Xbox Series X will ONLY get 60 if your HDTV has VRR, which the majority of TVs in the US do not unless purchased recently. So this is where PC will always win, in my opinion.

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That’s not what I got from it. Series S is locked at 1080p render resolution. Didn’t hear it was locked at 30 fps (depends on the TV you plug it into).

I swore that’s what Seb said – happy to clarify if I’m wrong. I do know he said 60 will only happen on VRR TVs.

Here. Microsoft Flight Simulator runs at 30fps on Xbox Series X|S (trueachievements.com)

yeh, but that goes for both afaik (and that article seems to reflect that as well), and both should be able to reach higher on variable refresh rate displays.

I could be wrong too of course :slight_smile:

true. Who knows! It will still look amazing on the next-gen xbox. No doubts.

I was so excited to see the draw calls drop from 3500 to 1500. Very simply draw calls are calls to the graphics card to draw some stuff on the screen and they impact both CPU and GPU performance. The more draw calls a game has the longer it takes to render a frame so to see the number drop by more than 50% is a huge improvement. This means that everyone is going to get a big performance improvement regardless of whether our PC’s were GPU or CPU bottlenecked before.

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