Digital Foundry Article Technical Discussion Archive [2014]

[Shortbread]

Digital Foundry: Hands on with the Destiny PS4 beta

It remains a sight to behold for all the right reasons; the 1080p resolve on PS4 is intact of course, as backed by the FXAA post-processing seen in the alpha. For the sake of presenting Bungie's gorgeous skybox designs, plus the vast acreage of Old Russia as seen from the highest points, this pixel count does the game a great service. Detail is rendered from a great distance while outside - with little pop-in aside from small rocks and rubble fading into view while boosting with a Sparrow.

Its strong visual assault aside, Bungie's alpha experiment wasn't all smooth sailing. In fact, we noticed at the time a locked 30fps read-out from our tools, with the average frame-rate showing little threat of dipping to the nether. That said, in practice the game clearly feels less smooth than it ought to, and this is where the principle of frame-pacing comes in.

Unfortunately, the beta version of Destiny continues to show signs of an uneven spread of frames, which while averaging out at the promised 30fps, produces a judder sensation to lateral camera movement. As a shooter played largely from the first-person view, the camera pivots more aggressively than most games, making this issue easier to pick out. It's very much playable, but we feel Bungie is doing itself a disservice given its in-house engine is clearly capable of pushing out a rock-solid frame-rate.

 

[zed]

I had a look at the DF site

http://images.eurogamer.net/2013/articles//a/1/6/9/4/0/2/2/1.bmp.jpg
personally it doesnt look that good, regardless.
but why on earth did DF think to convert from bmp -> jpg you just rename that .bmp file as .jpg to reduce the filesize (its 2.4mb) [smile]

 

[djskribbles]

I noticed the juddery framerate in the alpha and was hoping Bungie would fix that for the beta, but I still noticed it. Hopefully DF can reach out to Bungie and they can fix it.

 

[HTupolev]

I noticed the juddery framerate in the alpha and was hoping Bungie would fix that for the beta, but I still noticed it. Hopefully DF can reach out to Bungie and they can fix it.

Bungie is at least aware of it. Urk responded on the first page of the gaf thread for this article, saying they might even fix it during the beta.

 

[djskribbles]

Thanks. Great news.

It's not horrible, but it's not as smooth as it should be.

 

[London Geezer]

I do wonder why a lot of games on PS4 (don't know about X1) seem to be released with this very strange frame ordering bug, or whatever they call it, which creates the judder even though the game is running at a stable framerate. So very odd.

 

[AlNom]

It's been an issue for Bungie games for a long while now, actually - engine issue. Same thing happened with NFS at launch, but it was fixed.

 

[Globalisateur]

I wonder if it's not a way to hide framerate drops: instead of a regular framerate drop (or screen tearing on a double buffer) they do this instead because on the video this frame pacing issue is not constant or even periodic, it's apparently mainly occuring during the most action packed scenes.

 

[Shortbread]

I wonder if it's not a way to hide framerate drops: instead of a regular framerate drop (or screen tearing on a double buffer) they do this instead because on the video this frame pacing issue is not constant or even periodic, it's apparently mainly occuring during the most action packed scenes.

AMD GPU's always (well not always, but you get my drift), had/has some type of weird frame pacing issues. Not saying it's completely hardware related dealing with Destiny, but the driver/API could be effecting Destiny engine slightly. Just a guess...

 

[London Geezer]

AMD GPU's always (well not always, but you get my drift), had/has some type of weird frame pacing issues. Not saying it's completely hardware related dealing with Destiny, but the driver/API could be effecting Destiny engine slightly. Just a guess...

If that's true, that's teally not ideal. How can that happen, if it's a known issue?

 

[Shortbread]

If that's true, that's teally not ideal. How can that happen, if it's a known issue?

Hopefully I'm wrong about the situation, it's just a guess. AMD's multi-GPU setups tend to exhibit the issue more than anything… however, its single GPU’s aren’t totally without frame pacing issues as well. There's a sh** load of articles about AMD’s situation… but it has gotten better over time.

http://www.anandtech.com/show/7195/amd-frame-pacing-explorer-cat138

In an off year that hasn’t seen too many new product releases thus far, this has been anything but a dull time. For the better part of a year now the technology journalist community – spearheaded by The Tech Report’s Scott Wasson – has been investigating the matter of frame pacing and frame timing on GPUs. In applying new techniques and new levels of rigor, Scott found that frames were not being rendered as consistently as we had always assumed they were, and that cards that were equal in performance as measured by frame rates were not necessarily equal in in performance as measured by frame intervals. It was AMD in particular who was battered by all of this work, with the discovery that both their single-GPU and multi-GPU products were experiencing poor frame pacing at times. AMD could meet (and beat) NVIDIA on frame rates, only to lose out on smoothness as a result of poor frame pacing.

 

[3dilettante]

The pacing concerns in that article are related to the PC driver and DX runtime model.
The console versions should leave more discretion--and blame--to the software.

 

[imaxx]

The pacing concerns in that article are related to the PC driver and DX runtime model.

yeah, I dont really understand wtf the GPU has to do with these software issues.
Sony has its own GPU driver - the gnc(x) or such, dont remember atm- which is much thinner than AMD counterpart for windows - likely MB thinner.

 

[Shortbread]

The pacing concerns in that article are related to the PC driver and DX runtime model.

True.

And excuse my ignorance on the subject… but, doesn’t AMD still provide technical support (drivers/updates) dealing with its GPU’s within the XB1/PS4? I’m not talking in the framework model of the PC… but more so any improvements that directly addresses any broad issue(s) specifically affecting their IPs.

Edit: Not that I'm saying its hardware related, could be strictly software related.

 

[3dilettante]

Various stories about driver updates and SDK changes seem to put the console makers in the driver seat for much of it, although AMD could still be involved.

 

[imaxx]

True.

And excuse my ignorance on the subject… but, doesn’t AMD still provide technical support (drivers/updates) dealing with its GPU’s within the XB1/PS4?

Why? Both has custom drivers. AMD is not involved it those. Updates are likely to refer to the AMD portion's of code they might still use, which is likely to be limited.
For sure, it's not a driver, given each of them has its own custom driver model.

 

[ERP]

Various stories about driver updates and SDK changes seem to put the console makers in the driver seat for much of it, although AMD could still be involved.

The ICE team wrote the "driver" on PS4, ATI was not involved. I'd imagine the same was true on the MS side of things.

 

[Pixel]

The ICE team wrote the "driver" on PS4, ATI was not involved. I'd imagine the same was true on the MS side of things.

An Anandtech article writes that AMD author the drivers for these consoles.

?

As the supplier of the APUs in both the Xbox One and PS4, AMD is in a very interesting place. Both of these upcoming consoles are based on their GCN technology, and as such AMD owns a great deal of responsibility in developing both of these consoles. This goes not only for their hardware but also portions of their software stack, as it’s AMD that needs to write the drivers and AMD that needs to help develop the APIs these consoles will use, so that the full features of the hardware are made available to developers.

http://www.anandtech.com/show/7371/understanding-amds-mantle-a-lowlevel-graphics-api-for-gcn

 

[ERP]

Then anandtech is incorrect.
Though I believe the shader compiler is based on AMD code, libgcm etc. were written by the ICE team.
Obviously AMD provided technical support.

 

[Brad Grenz]

I thought the whole "mono driver" thing implied MS was adapting the Xbox One's driver from the existing AMD GPU DX11 driver code-base. According to them the whole point of the mono driver was that it had been stripped of all the support for other products and configurations.