Alcifer Comments

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  • Digital Foundry vs Forza Motorsport 6

  • Alcifer 17/09/2015

    @Milouse refraction from screenspace water droplets and heathaze isn't new, it's surprisingly simple to implement. They do look nice though.

    There are plenty of games on PS3/360 that use it.
    Reply +8
  • Ashes of the Singularity: the first DX12 gaming benchmark tested

  • Alcifer 18/08/2015

    @mdeneuve, the cost of state management might be to do with the GPU being a pipeline with multiple stages and always trying to maintain maximum occupancy of every stage. As one batch filters through you want another to start with a minimal gap in between so the drivers have to work out exactly when and how to change state to achieve that.

    Low level APIs on consoles, like GCM on PS3, allow developers to manually build and maintain command lists but also exposed a lot of the quirks of the hardware that are key to performance. With the high level APIs these are handled by the driver invisibly but not necessarily efficiently, changing states in the wrong order or using specific calls could hammer performance.

    With DX12 and Vulkan on PC there seems to be a sort of middle ground where we still have a certain amount of hardware abstraction for many different architectures, so programmers won't necessarily have access to all the little hardware features that aren't standard. That might be what's going on with this benchmark and the Nvidia cards, they're issuing state calls in an order or frequency that the architecture isn't designed to expect (perhaps to do with resource binding where GCN has an advantage).

    DX12 and Vulkan offer some really interesting opportunities for graphics programming, not necessarily just on PC. I don't think they'll replace high level APIs like DX11 and OpenGL though, more likely co-existing with them as an alternative.
    Reply +2
  • Alcifer 17/08/2015

    @mdeneuve, the main reason for batching draw calls is that changes to GPU state have traditionally had quite a high overhead on the driver side. The GPU runs linearly through a command buffer effectively configuring itself for every draw call before executing it, this buffer requiresvarious checks to ensure it doesn't break things. So the ideal rendering method was to render thousands of triangles at a time with the same state.

    Low level rendering APIs potentially reduce the overhead of state management, allowing the developer to change state more often with less cost and so have many smaller batches. In theory that lets a game use many more materials or lights per object.

    Multi-threaded support for command buffer creation was already available in DX11 but was poorly implemented, the main thread needed to perform all the additional checking once the worker threads submitted their command buffers. On DX12 this will become the responsibility of the developer who has to manually handle synchronisation and ensure command buffers are dealt with in order (most GPUs will still only have a single thread of command execution).

    As this benchmark seems to indicate though, it potentially moves the state change bottleneck from the driver to the hardware. Different hardware will have different costs associated with setting up draw calls. Something the DX11 drivers could account for during the command buffer translation/validation phase.
    Reply +11
  • Less than two months from launch, Tony Hawk's Pro Skater 5 changes art style

  • Alcifer 06/08/2015

    That must have taken a graphics programmer all of 30 minutes to implement. Reply +9
  • The re-engineering of Ethan Carter

  • Alcifer 22/07/2015

    @frunk the linked Gamasutra article puts that sentence into a little more context.

    In UE4, lightmaps are meant to contain indirect (bounced) lighting only; setting light source mobility to "static" causes lightmaps affected by it to also include direct lighting, but it is an exceptional situation, not the default. Such lights are not even considered for dynamic lighting. This means that they don't have specular highlights. None at all. You can probably imagine how flat and uninteresting the game looked because of that.
    In UE3 the engine obviously still considered baked light sources as dynamic and calculated the specular term in real time (based on light and viewer position) before adding it to the baked direct and indirect diffuse terms.

    My understanding is that to fix this he created a separate forward lighting pass which calculated the specular highlight and added it over the top as an emissive layer (light given off by the material itself). Effectively recreating the model used in UE3.

    This addition of the specular term would break the energy conservation principle at the heart of PBR (light reflected from a material should never exceed light received).
    Reply +5
  • Sony sets up North West Studio to make Project Morpheus games

  • Alcifer 19/05/2015

    I remember submitting a pitch document for a concept before Move was released, that would work pretty well with Morpheus. The two devices seem to compliment one another really well. Oh well... Reply 0
  • PlayStation 4 lifetime sales pass 22.3m worldwide

  • Alcifer 30/04/2015

    Does this make Microsoft Sauron? And Phil Spencer the Witch King?
    Reply +39
  • Microsoft demos Windows 10 hologram support

  • Alcifer 30/04/2015

    That's one way to make monitor/TV/Phone manufacturers slightly nervous.

    Given a sufficiently high resolution and unobtrusive AR display there really is no need for the plethora of screens we currently use.
    Reply +13
  • Digital Foundry: Hands-On with Project Cars

  • Alcifer 21/04/2015

    @Dantonir Goodbye. Reply +2
  • A Command & Conquer: Generals mod these many years later?

  • Alcifer 26/03/2015

    Generals was easily my favourite C&C title. So many hours put into multiplayer and co-op against the AI :D

    The Humvee of doom (3 rocket launcher troops and 2 snipers in a Humvee, all fully upgraded) was stupidly powerful if you micromanaged it.
    Reply +9
  • PlayStation Plus' free November offerings revealed

  • Alcifer 29/10/2014

    @dadrester, I think I've been looking forward to playing it for about 4-5 years :) Reply +2
  • Alcifer 29/10/2014

    @dadrester :D Reply +4
  • Aliens versus Predator retrospective

  • Alcifer 05/10/2014

    But to do so would be dishonest to the 12-year-old me who first played AVP in 1999
    Now I feel old.

    I remember playing this at uni on the first PC I bought with my own money. The marine campaign was terrifying at 4am (further heightened by a couple of litres of Asda own brand Red Bull substitute).

    Sadly what AvP2 gained in polish it lost in atmosphere and character. I'm pretty sure I finished it but it never had the same feeling of isolation and threat.
    Reply +14
  • Digital Foundry: Hands-on with DriveClub

  • Alcifer 06/09/2014

    I'm amazed he made it through a whole interview on real time lighting without once saying "It's mathematically correct." :D

    Looks really stunning, it really shows how much a good lighting model can bring in terms of atmosphere. Still, it would have been interesting to know if they could have hit 60fps at 720p or using Guerrilla's interlaced 960x1080 method.
    Reply +2
  • First footage of From Software's Project Beast

  • Alcifer 30/05/2014

    @marcofdeath except Hynix weren't producing HBM in 2013, they're only supposed to start ramping up production in the second half of this year, so it doesn't look like either console is using it.

    Besides, Chipworks have done a teardownn of the XB1.
    Apparently it's using H5TQ4G63AFR DDR3 SDRAM.

    In that light, I'm really looking forward to Nintendo's next console :D
    Reply +3
  • Hardware Test: PlayStation 4

  • Alcifer 13/11/2013

    Looks like the PS4 has AMD's TrueAudio tech, the same as the new Radeon cards. Reply +6
  • Digital Foundry vs. Dead Rising 3

  • Alcifer 12/11/2013

    holy bedjezus... that looks like a boring game... where's the tension?
    In the dramatic pauses between frames ;)
    Reply +8
  • Eurogamer's guide to system swansongs

  • Alcifer 10/11/2013

    @dogmanstaruk, you usually see the system's preowned section in Game getting clogged up with 3-4 iterations of Fifa as the system dies. Like some terminal degenerative disease. Not really what I'd call a swansong. Reply +27
  • Face-Off Preview: Battlefield 4 next-gen vs. PC

  • Alcifer 30/10/2013

    COD confirmed to be 720p XB1 and 1080p on PS4.

    There may be a pattern appearing here...
    Reply +4
  • Alcifer 29/10/2013

    @Suarez07, there's a tweet about the XBone AO on the NeoGAF thread.

    You can actually see it in the last comparison shot quite well in the DF article. Look at the guy on the left's gun and you'll see it shadow the elevator doors on the PS4 and PC images. Also this comparison shows it pretty well here.
    Reply 0
  • Alcifer 29/10/2013

    @Suarez07, DICE have already commented that the XB1 version is not final anyway, it doesn't have AO enabled.

    For a proper comparison of the game I'd wait for DF to compare final builds anyway. Enabling AO, and possibly AA, will most likely reduce the framerate further. With any luck DF will get better captures to work with when they don't have limited access, I interpreted the article as them capturing each platform on separate days.

    As it stands the comparison confirms what most people have been saying for a while, that the PS4 is more powerful and the XB1 versions of games are lagging behind in development.
    Reply +4
  • Editor's blog: Battlefield 4 Face-off Preview Q&A

  • Alcifer 29/10/2013

    The big question is - if ambient occlusion affects light as it hits a surface based on the surface itself and adds a softening effect similar to ambient light, does this combined with the limited RGB of the XB1, mean that when AO is added to the X1 version, we'll see similar softening as is appearing in the PS4 version?
    While it is true that AO tends to give a smooth shading effect it should not impact the clarity of texture detail in the final image, just darken areas of the image.

    It's more likely that the PS4 version is applying an additional shader based AA or motion blur pass that blurs the image. In the case of character faces in particular this could be part of the sub-surface scattering applied to skin.

    Fixing the RGB output of the XB1 will certainly reduce the contrast in the images, the DF captures make many textures appear "sharper" than those in the PC exemplar.
    Reply +4
  • Watch Epic explain Unreal Engine 4's fancy pants visual effects

  • Alcifer 24/10/2013

    @dogmanstaruk, it's pretty ironic considering all the "PS4 can't do 1080p 60" comments after the initial XBox reveal.

    I'm beginning to suspect they designed a system that could render 360 games at 1080p and didn't expect developers to do anything beyond that.
    Reply +1
  • Introducing Games of the Generation

  • Alcifer 21/10/2013

    I think the current gen still has a year or two in it, at least on some platforms. Will certainly be keeping an eye on these lists to see if there is anything really awesome that I've missed though.

    Not sure what my top 5 would be but I think Nier, Uncharted and Assassin's Creed 2 are definitely up there.
    Reply 0
  • Kingdom Hearts 3 PS4, Xbox One gameplay video

  • Alcifer 15/10/2013

    @Rogueywon, the cutscenes for Re:Coded and 356/2 Days are included in the HD remakes on PS3, so there's at least an option to avoid playing those two.

    No idea what they're planning to do with 3D regarding the HD remakes. Maybe a digital Final Mix closer to KH3 release...
    Reply 0
  • Jedi Knight 2: Jedi Outcast retrospective

  • Alcifer 13/10/2013

    I put a ridiculous amount of time into this game, and Jedi Academy, mostly just reloading checkpoints to replay fights over and over again, it never got dull. I think only Bushido Blade came anywhere near these games for visceral melee combat.

    That Lucas Arts could make such a mess of the Force Unleashed when these games existed is probably proof enough that they had no idea what they were doing. For all its gritty and dark atmosphere, watching Starkiller try to beat a storm trooper to death with his Fisher Price Padawan's first lightsabre was just sad.
    Reply +5
  • Assassin's Creed 4 director wants to take the series to ancient Egypt

  • Alcifer 12/10/2013

    I'm no historian, but could someone enlighten me on this "recent evidence"?
    I'm no historian either, but I think he might be referring to the discovery of towns built to house the workers who built the pyramids. These apparently show that the pyramids were built by gangs of seasonal labourers, rather than slaves as previously thought.

    I don't think this is evidence that slaves weren't used in ancient Egypt, just that the pyramids weren't built by armies of slaves but instead large numbers of normal Egyptians.
    Reply 0
  • Drakengard 3 will be a digital-only title on PS3 next year

  • Alcifer 10/10/2013

    Looks like it will be available at retail in the US. Will be importing this one then.
    Reply 0
  • Digital Foundry: the complete Xbox One architects interview

  • Alcifer 08/10/2013

    @khanthony, the main issue is that newer techniques may not be picked up by third parties who will want their games to be playable on all major platforms.

    In the previous generation full deferred shading was largely limited to Sony first party titles because it was not suitable on the 360 which would not support a G-Buffer larger than 10MB.
    Reply +2
  • Alcifer 08/10/2013

    @Kretenn, there is a difference between making a subjective comparison of Forza 5's graphics to other next gen titles and looking critically at the techniques they're using. Aside from an increase in resolution and quality, they don't appear to be doing a great deal that they didn't already have implemented in some form on Forza 4. The results look good, but they don't say anything about the graphics capabilities of the XB1.

    I would take Goossen's figures regarding ROPs with a pinch of salt. There is only a direct relationship between bandwidth and fillrate if none of the pixels are being rejected (depth/alpha testing). 16 ROPs will be suitable for scenes with little overdraw, like those in Forza 5 or Ryse, which to the best of my knowledge, is running at 900p 30fps. The fact that the game with the highest rate of overdraw, Dead Rising 3, is using dynamic resolution suggests that they are already having problems with fillrate or shading.

    Considering for the latter part of the current generation PC graphics have been largely crippled by the capabilities of both consoles, it would be a shame if PC and PS4 are held back by the limitations of the XB1 due to its GPU and RAM set up.

    Even the architects sound like they were disappointed with some of the compromises they had to make, rejecting GDDR5 and then a potentially much larger eDRAM pool. They certainly made the best system they could within the constraints they had, but they were pretty unlucky in what they had available to work with.
    Reply +1
  • Alcifer 07/10/2013

    @Ninja_skill, the cloudlight examples are really interesting and the latency figures might suggest the calculations could also be done locally across multiple frames.

    I'm not sure I'd expect games to be using the cloud for these sort purposes any time soon though. It would require GPU based servers, like NVidia's GRID and probably consumes hundreds of times more computing power than Titanfall uses for its servers. Even at a reduced rate and sharing data across multiple users that doesn't sound viable.
    Reply +1
  • Alcifer 06/10/2013

    @khanthony, not to downplay Azure, which is a very interesting resource, but I do think Sony also has a strength in their online offering.

    At least for the present, PSN is a much more open platform than Live, allowing developers to use their own servers and allow cross platform play, which is why games like FF:XIV, Timesplitters and War Thunder are being released on PS4 but not XB1.

    As with the hardware architectures, these are two very different approaches so it should be interesting see how things pan out.
    Reply 0
  • Alcifer 06/10/2013

    @SF1, we've heard about hardware for encoding and decoding audio and video on PS4. So it does certainly have some fixed function hardware. Though most of what is confirmed has come from interviews early on after the reveal. There are also some nice details about their hUMA setup but they're pretty technical.

    I agree it would be very nice to have Sony publish an overview of the system architecture as a whole to be able to make more direct comparisons.
    Reply +4
  • Alcifer 06/10/2013

    @CMcK, the distinction I'd make between the Cell on the PS3 and the GPU on the PS4 is that there is nowhere near as much requirement to use it for any particular purpose.

    The Cell chip effectively gave the PS3 only 33% of the CPU of the 360, the rest of it being made up of SPUs which required very specific program architecture. In the case of the PS4 (based on current clockspeed and accounting for SHAPE) it has maybe 80% of the CPU power of the XBox as well as having 50% additional GPU compute.

    To balance the comparison of the two next gen consoles: I'd probably say that if the PS4 uses brute force, it also has more flexibility in how those resources are applied. The XB1 is perhaps more efficient in the resources it has, but it is much more rigid in how those can be used.

    A good comparison of these from launch titles would be Forza 5 and KZ:SF. Forza 5 makes excellent use of the XBox system capabilities, but it could probably be implemented with only minor changes on the PS4. KZ:SF pushes heavy graphics workloads for its lighting and rendering, making use of a huge G-buffer (5 floating point buffers), which could not be replicated on the XBox.
    Reply +3
  • Alcifer 06/10/2013

    Ultimately this generation of consoles are very similar and it will be fascinating to see which approach works well most consistently. The brute force approach Sony have taken or the efficient approach Microsoft have chosen.
    Not picking on you in particular, but why do people think the XBox is more efficient than the PS4, or that the PS4 approach is brute force?

    You could equally say, overclocking the whole system and tacking on multiple fixed function processors is brute force, and adding extra CUs and ACEs with flexible memory access is a more elegant/efficient solution.

    These are clearly two very different solutions to enhancing what is effectively the same base hardware, it just seems odd that they're characterised in this way.
    Reply +7
  • Alcifer 06/10/2013

    @Ninja_skill, I think you're right, virtual memory on the GPU goes far beyond just more efficient use of texture memory, although that is a big improvement.

    Sony have already presented an example of sparse voxel cone tracing for lighting using PRT in their GDC presentation on PSSL. It should be interesting to see what developers are going to do with this stuff and hUMA.
    Reply 0
  • Alcifer 05/10/2013

    @khanthony, the article you posted a link to earlier suggests that GNMX, the high level API, is actually closer to D3D11 than OpenGL. Along with PSSL being very similar to HLSL, but with lower level access to hardware, helps developers port games from PC to PS4.

    "Most people start with the GNMX API which wraps around GNM and manages the more esoteric GPU details in a way that's a lot more familiar if you're used to platforms like D3D11.
    - Reflections' expert programmer Simon O'Connor
    Reply +2
  • Alcifer 05/10/2013

    Sony already went out and said it uses custom OpenGL
    Do you have a source for this?
    Reply +1
  • Alcifer 05/10/2013

    @OrbitScant, Interesting. The first slide about different heaps and buses puts me in mind of the interview with The Crew developers.

    There's a lot more detail here:
    Reply +2
  • Alcifer 05/10/2013

    @deesmith, I think a lot of misconceptions arise from people automatically assuming OpenGL is the only alternative to D3D. Although Sony did implement OpenGL ES as a high level alternative to GCM on PS3.

    The DirectX on PS4 comes from DirectX versions being used to describe GPU feature sets. Both consoles use the same Sea Islands architecture and both support the DX11.2+ feature set, only the XBox supports the actual D3D11.2 API with the PS4 accessing the same features through GNM and GNMX (although GNMX could be a clone of the D3D11.2 interface with their own implementation).
    Reply +6
  • Alcifer 05/10/2013

    Sony's reliance on OPENGL actually may limit optimization on some levels because they do not own the OpenGL codebase which by its nature cannot cater to any specific hardware. This may be why they have less actual AAA games at launch for exclusives - just a guess.
    There isn't actually any one OpenGL code base. It's an open interface standard that platform holders have to implement themselves in order to support it.

    This is pretty moot as the PS4 doesn't support OpenGL. The developers of The Crew have stated that Sony are using their own low level graphics API called GNM (possibly similar to mantle) and a high level API wrapper with source code called GNMX (possibly similar to D3D11).
    Reply +7
  • Alcifer 05/10/2013

    The more I read about the lengths to which Microsoft went to build multimedia functions into the XBox the more it sounds like a big gamble. They're betting on the strength of their gaming brand to get these features into homes and then try to expand that market.

    However, a lot of this stuff sounds like it would be better built into a TV than a console (snap, Kinect, etc.). There are already multiple HDMI inputs, it's the main device used for all these features so it's the first to be turned on.

    They might have been better partnering with TV manufacturers to push Windows OS, Kinect and smart glass functionality than creating a hybrid set top box/console.
    Reply +2
  • Alcifer 05/10/2013

    It's interesting that MSoft always talk about cache coherent memory bandwidth and never mention the fact that PS4 can bypass the L1 & L2 caches completely.
    Indeed, Cerny was also very specific about adding extra flags to allocations so they could selectively flush GPU cache lines to maintain coherence. Without this the GPU would stall completely each time coherence needed to be enforced, flushing all cache data regardless of whether it was GPGPU or graphics related.

    I assume Microsoft would have the same problem but they don't go into that much detail.
    Reply +4
  • Alcifer 05/10/2013

    My take on it is that when you buy a graphics card, do you go by the specs or do you actually run some benchmarks?
    Does he mean two AMD Radeon cards in the same family?

    If so, it's more of a price/performance trade off than a question of which is more powerful, I wouldn't expect a 7850 to outperform a 7870 but I would expect it to cost less...
    Reply +16
  • Alcifer 05/10/2013

    Reading the interview in full was much better than the articles it spawned, I appreciate seeing the points put across in order and their full context. Though I can understand that so much text is daunting.

    I get the feeling that Microsoft have been very insular, developing the console based solely on their own internal goals and experiences where Sony have made a point about reaching out to third parties.

    There's a lot of emphasis on multi-tasking behind the earliest decisions (8GB DDR3, virtualisation) clearly looking to expand their market and feature set beyond gaming.
    Their gaming related choices seem to be informed largely by the design of the 360 (eSRAM, CPU, fixed function offload, Kinect) and its strong market position and ignoring some of its inherent weaknesses (difficulty with deferred shading).

    When they talk about tweaking their setup (overclocks and CU numbers) with regards to existing titles, they seem to be doing so with exclusives, software that has already been balanced to run on their architecture. Obviously if a game has little emphasis on shader processing (is not pushing the limits of 12CUs) then an increase in the number of CUs will have virtually no impact on performance.

    The performance of multi-platform titles will say an awful lot about how well Microsoft's own priorities and balance fit with the industry at large, and by extension how well Sony have delivered too.
    Reply +26
  • Assassin's Creed Heritage Collection bundles five Assassin's Creed games

  • Alcifer 04/10/2013

    @dogmanstaruk, totally agree, Ezio really made the AC series for me, especially with the mess they made of Desmond's part. They should have included Embers with this. Although I'm sure people can find it on Youtube if they want. Reply +1
  • Microsoft to unlock more GPU power for Xbox One developers

  • Alcifer 04/10/2013

    I'm a fairly technically minded person but I can't figure out whether or not this is true.
    It's a fairly laboured example designed to prove a point about balance.

    It predicts that developers would enable depth testing without having it reject any pixels (no overdraw), which defeats the point of depth testing.

    If any pixels were rejected, by their own calculations, they'd be ROP bound with only 16 ROPs. If they turned off depth testing they'd still be eSRAM bandwidth limited because they'd hit the 109GB/s limit for writes (even if they had more than 16 ROPs).

    Also as RL points out they're completely ROP bound when rendering 8 Bytes per pixel (4 read, 4 write), such as when rendering shadows or Z-pre-pass.

    Edit: As Goossen says:
    parts of the frame can be fill-rate bound, other can be ALU bound, others can be fetch bound, others can be memory bound, others can be wave occupancy bound, others can be draw-setup bound, others can be state change bound, etc. To complicate matters further, the GPU bottlenecks can change within the course of a single draw call!
    The bigger the number, the less likely a part of the GPU will be the bottleneck. Hence bigger numbers, better performance for those parts of the pipeline.
    Reply +2
  • Alcifer 03/10/2013

    Just like our friends we're based on the Sea Islands family.
    In the last article Goossen confirmed both consoles were using the same GPU architecture.
    Reply +3
  • Alcifer 02/10/2013

    @DopeBoy3010, yes, apparently the ps4 has a similar chip for scaling and compositing, although only for two layers rather than three.
    Reply +2
  • Could AMD's Mantle revolutionise PC gaming?

  • Alcifer 26/09/2013

    @_tangent, the fully programmable graphics pipeline was a future direction, I don't think there will be much information available.

    At the moment graphics pipelines are split up into various stages, some of which are fully programmable through shaders and others which offer limited fixed functionality (like blending, raster operations, etc.). I think what AMD were talking about is writing C++ like code that compiles for the GPU and actually writing libraries to implement the whole rendering process in software.

    It sounds like a future that Intel and Sony et al were reaching for with Larrabee and Cell.
    Reply +2