Oct 21 / Ozymandias

Clarifying Thoughts on High Definition Game Rendering

game-hardware, game-industry, playstation-3, xbox-360

I was talking to Bruce Dawson, one of our senior software design engineers here, about some questions I had around 1080i and 1080p. Frankly, I was particularly curious about why Sony has continued harping on 1080p as being “TrueHD”, especially since the 360 has enabled 1080p output as well (coming soon to homes near you!) I was trying to figure out if I was just missing something, and his emailed answer was particularly clear and helpful to me, and since there’s nothing confidential here I thought I’d share it with you.

The really interesting statistic that popped for me is how much less time a game console has to render a 1920×1080 scene versus a 1280×720 scene. (Remember this is on the same console, whichever one you like. This is not a comparison of different console’s rendering capabilities to each other.) Simply put, for a 1080i/p game the console has 55% less time per pixel to render any special effects, anti-aliasing, illumination, etc. than for a 720p game. Yes, even Resistance has fallen off the bandwagon and admitted they can’t hit 1080i/p as previously claimed. (It also helps explain why Gran Turismo HD is so underwhelming.)

Anyway, Bruce’s text is below. Hope it helps clarify a few things for you!

Many developers, gamers, and journalists are confused by 1080p. They think that 1080p is somehow more challenging for game developers than 1080i, and they forget that 1080 (i or p) requires significant tradeoffs compared to 720p. Some facts to remember:

2.25x: that’s how many more pixels there are in 1920×1080 compared to 1280×720

55.5%: that’s how much less time you have to spend on each pixel when rendering 1920×1080 compared to 1280×720—the point being that at higher resolutions you have more pixels, but they necessarily can’t look as good

1.0x: that’s how much harder it is for a game engine to render a game in 1080p as compared to 1080i—the number of pixels is identical so the cost is identical
There is no such thing as a 1080p frame buffer. The frame buffer is 1080 pixels tall (and presumably 1920 wide) regardless of whether it is ultimately sent to the TV as an interlaced or as a progressive signal.

1280×720 with 4x AA will generally look better than 1920×1080 with no anti-aliasing (there are more total samples).

A few elaborations:

Any game could be made to run at 1920×1080. However, it is a tradeoff. It means that you can show more detail (although you need larger textures and models to really get this benefit) but it means that you have much less time to run complex pixel shaders. Most games can’t justify running at higher than 1280×720—it would actually make them look worse because of the compromises they will have to make in other areas.

1080p is a higher bandwidth connection from the frame buffer to the TV than 1080i. However the frame buffer itself is identical. 1080p will look better than 1080i—interlaced flicker is not a good thing—but it makes precisely zero difference to the game developer. Just as most Xbox 1 games let users choose 480i or 480p, because it was no extra work, 1080p versus 1080i is no extra work. It’s just different settings on the display chip.

Inevitably somebody will ask about field rendering. Since interlaced formats display the even lines on one refresh pass and then the odd lines on the next refresh pass, can’t games just render half of the lines each time? Probably not, and even if you could you wouldn’t want to. You probably can’t do field rendering because it requires that you maintain a rock solid 60 fps. If you ever miss a frame it will look horrible, as the odd lines are displayed in place of the even, or vice-versa. This is a significant challenge when rendering extremely complex worlds with over 1 million pixels per field (2 million pixels per frame) and is probably not worth it. And, even if you can, you shouldn’t. The biggest problem with interlaced is flicker, and field rendering makes it worse, because it disables the ‘flicker fixer’ hardware that intelligently blends adjacent lines. Field rendering has been done in the past, but it was always a compromise solution.

Ed

Wouldn’t 1080p more difficult than 1080i if you were pushing more than 30 frames per second?

1080i is always 60 half frames per second.. 1080p can be up to 60 full frames per second.

Presumably something like Hexic or Lumines would look better at 1080p/60 than at 1080i, just because of the higher framerate.

I think the news that Resistance is going back to 720p is a sign that the 720/1080 tradeoff exists and is huge. I have a 1080p TV, that takes 1080p over vga, and the VGA cable. But I’d still rather have games render natively at 720p with lots of eye candy than at 1080p without it, so I’m glad Resistance is 720p and I’m glad Saints Row is 720p.

But I do think simple XBLA games could easily be 1080p without any loss in goodies, and I bet games like Table Tennis could also have been 1080p.

I suppose it could, in theory, be a simple patch to enable the 360 to render natively at 1080p for some games. I might be looking forward to that patch.
http://www.satori.org madsax

You’re assuming here that the graphics chip is not capable of field rendering – and that is not necessarily a valid assumption. There have been previous graphics chips which had knowledge of interlacing and so, for example, a 480i screen was actually rendered into the frame buffer with half the number of rows in order to save memory. It’s true!

I’m not saying the PS3 does this. I’m just saying.
THE MAC GOD

These are things I’ve been wondering for a while… but no one has answered them well enough:

So, I have a Toshiba HDTV (it has HDMI, but not vga…), and it only has two resolutions: 540p and 1080i (the same resolution, just p or i).

Now, from what I’m reading above, it looks like I could be getting better framerates if I lower my 360 to 720p.

The only question is, what would I set my TV to? I would assume 1080i… the console could output 720p and the tv could upconvert it…

Any ideas?

Thanks!
James

The Xbox 360 renders at 720p regardless of what you set it to. If you have a 1080i/p TV then it’s simply a matter of whether you want the Xbox 360 or your TV to upscale (excluding the few 1080p games that might be made).
Andrej

James — that’s not correct. The 1080p support announced on the 360 means that it supports a 1920×1080 buffer, outputting to 1080p if your set supports it. Games can be designed to use this or they can upscale from 720p. For 720p games, you’re right–then it’s a decision of which device you want to hande the upscaling (the 360 or your TV).
Adrian

Last time I checked, there was only 1 tv on the market capable of accepting a 1080p input. Your expensive sony 1080p tv? don’t accept the input, it takes a 720p input and upscales it to 1080p making it look worse(has to guess what’s between the lines). The only TV that accepted 1080p input was the mitsubishi DLp and only through a computer connection then.
Rob

Adrian, several manufacturers make 1080p, Westinghouse makes a whole line of 1080p plasmas, for example.
Ed

Sharp, LG, JVC, Samsung, Mitsubishi, Sony, Westinghouse, Fujitsu, HP, Panasonic, Pioneer and Sceptre all make 1080p displays/projectors.
Ed

Oh, and all of the above can accept a 1080p source over at least one connection.
Anonymous

This entire article assumes that games today are being rendered at 1920×1080, and then interlaced. However, systems like the Xbox 360 actually render a "squished" image at 1920×540, and then double it to get a 1080i signal. The PS3 does the same thing. It doesn’t alternate fields when doing this. It just doubles the vertical resolution to make the image not squished, but it means that each line is doubled. It’s not that noticeable at that screen res, but it’s there.

This is also why GT4 on the Playstation 2 could handle a 1080i output. The only game on the system to do so, I believe. But it couldn’t do 720p, even though the system could theoretically put that out over component, because presumably that would actually require more power than 1080i would.
As my grandfather always

There’s a sucker born every minute.
ZyronEnder

The problem with HD technology is if the "last time I checked…" was more than 6 months ago, your information is out of date.

Today, there are many sets available right now at retail outlets such as Best Buy, etc. that accept and fully display the 1920x1080i/p signal without scaling. Sony XBR2 sets, Samsung 4×96 series, Westinghouse has a couple, as does the Sharp Aquos line, in plasma there is the Pioneer FHD1. There are others, and they are all new within the last 6 months (refer to http://www.avsforums.com).

xbox games list on the back the native resolutions that the game was designed for. Oblivion is one that was has the higher 1080i resolution capability. A game that does not list 1080i on the back will be upscaling to display on a 1080 supporting HDTV.
Carl

Seeing as I just bought a new Sony SXRD, it’s true LAST YEAR’s (05) XBR could NOT accept 1080p input, even though it was a 1080p native screen. However, the new a2000′s and XBR2′s both accept 1080p via HDMI, however not VGA. I’ve got my PC setup to it at 1920×1080 on DVI->HDMI, and its great. However, 360′s 1080p capabilities completely uninterest me until it can output it via HDMI. Becuase of all the TV’s that support 1080p input, most have HDMI, many have VGA(mine doesnt…damn), and almost NONE support it through component… So at the moment I’m just letting my 360 upscale to 1080i, and the tv deinterlace to 1080p.
ZyronEnder

The comment about rendering a "squished 1920×540" image is incorrect.

Please re-read the article, it explicitly states that the 360 doesn’t do this but it has been a technique used in past systems.

One thing to keep in mind is that even if the console outputs 1080i correctly, a very large proportion of HDTVs available today do not correctly de-interlace the image, resulting in a similar "doubling" type problem. Here’s a link to http://www.hometheatermag.com that discusses the issue and shows test results of recent TVs:

http://www.hometheatermag.com/hookmeup//1106hook/
Pjotr

First fix the framerate and screen tearing problems at 720p before crapping on other consoles.

Thank you.
Drew

The new Splinter Cell supports 1080p on the Xbox 360. Once it’s out, we’ll all be able to judge for ouselves the difference between 720p and 1080p/i.
jothaxe

The only thing clear to me from reading this is that the author doesn’t fully understand the difference between 1080i and 1080p.

Rendering 1080i means you render exactly 1/2 of the full frame pixels each time (alternating between odd and even rows.) This means 1080i requires calculating exactly 50% of the pixels for 1080p.

For digital applications interpolation is often done on the interlaced frames so that a buffer has the full number of pixels but interpolation is never the same as true data.
The Evan

Huh, I never considered that all 1080 sources would have to be rendered and then interlaced, so there’s no cost trade-off between interlaced and progressive. For some reason I was just assuming a field-rendering setup (iirc this is how SLI setups work).
NEMESiS X27

I’m not too concerned with 1080p for gaming, I would much rather have a better looking more detailed/processed image than one with less detail and possibly at a slower framerate.

All I can see myself using 1080p for, will be with HD-DVD player and future Marketplace content that will eventually turn up in 1080p (although this hasn’t been confirmed).
somone said

ive only got a black and white tv so it dont make much difference to me!
bluescrn

Just about every 360 game I’ve seen had a *** framerate and tearing problems.

Forget 1080p. And consider going lower than 720p if it’s killing framerate and therefore hurting *gameplay*!

It’s shocking that on ‘next-gen’ consoles, 30fps is about the best you can expect even for *racing games*!

Current HD gaming truly sucks.
deboqi

PS3 is capable of rendering at native 1080p which is an impossible mission for xbox360.

That’s why Sony has continued harping on 1080p as being "TrueHD".
Hash

Bruce Dawson I have a simple question if you could ask bruce. if 1080p reduces the visual clarity of the game compared to the 720p version, Why then does the 1080p version of Playstation 3 NBA 2k6 look slightly better than the 720p Xbox 360 version of NBA 2k6 even though the looks are not about resolution, they are the extra effects added into the game.

Secondly why arent developers utilizing unified shaders properly? I have heard a major API update is coming to developers, is this true?
Graphics Geek

> Wouldn’t 1080p more difficult than 1080i if you were pushing more than 30 frames per second?

Either way you are rendering 1920×1080, so it’s the same.

> But I do think simple XBLA games could easily be 1080p without any loss in goodies

Yep, they don’t need to spend a lot of time per pixel, so they could run at 1920×1080.

> You’re assuming here that the graphics chip is not capable of field rendering

No, the article doesn’t assume it isn’t possible. It specifically says that it isn’t desirable. The display chips on any reasonable console will do some very careful averaging of even and odd lines (different fields) in order to reduce the interlaced flicker. Field rendering makes this impossible, and therefore field rendering is not desireable.

> Now, from what I’m reading above, it looks like I could be getting better framerates if I lower my 360 to 720p.

No, because the game can render at one resolution and then it is converted to your requested output resolution. Most Xbox 360 games render at 720p, so changing your Xbox 360 to 720p will probably make no difference, to performance or image quality.

> James — that’s not correct. The 1080p support announced on the 360 means

> that it supports a 1920×1080 buffer, outputting to 1080p if your set supports it.

No, the game decides on the frame buffer size. Then the console outputs that frame buffer at the resolution you have requested (480i, 720p, 1080i, or 1080p). Adding 1080p support to the display settings doesn’t not affect the frame buffer size.

> This entire article assumes that games today are being rendered at 1920×1080

Yep, because otherwise you get excessive flicker and other undesirable artifacts.

> The only thing clear to me from reading this is that the author doesn’t fully

> understand the difference between 1080i and 1080p.

> Rendering 1080i means you render exactly 1/2 of the full frame pixels each time

I thought the article addressed this. It’s called field rendering and it causes problems, like increased flicker. It also requires a rock solid 60 fps, which is difficult on modern games because of their complexity. Yes, games could do field rendering. Yes, it helps the performance problems of 1080 resolutions. But, since it makes games look worse (flicker really *sucks*) I really doubt it is a good idea.

> PS3 is capable of rendering at native 1080p which is an impossible mission for xbox360.

Given that PS3 has about the same graphical horsepower of the Xbox 360 (less, say some sources) this is a rather hopeful claim. Do you have any reason to believe that PS3 can handle 1920×1080 better than Xbox 360, or is this just based on Sony’s unsubtantiated bragging.
Chris

"> PS3 is capable of rendering at native 1080p which is an impossible mission for xbox360."

What kinda idiotic remark was that

THATS WHAT THE DASHBOARD UPGRADE IS ENABLING full native 1080p … so if a developer wants to use it they can…..

1080p is not some mythical magical resolution, most high end computers handle it stop being lame.

….

Now i hate to be an ass here but if the 360 cant handle the visuals the ps3 can… why does cod3 look better on the 360… why is the ai better on the exact same looking version of assassin’s creed on the 360… so stop pertending that the ps3 is some masterful machine…. cell is not the holy grail so stop acting as if it is. plain and simple

…

games normally render at 720p but a few chose to render native 1080i but very few because they can get better visuals in 720p than in the 1080… its a developers choice of balance, between resolution and visual effects… simple as that
calderracrusade

Wow. Incredibly interesting! I always thought 1080p was massively tougher than 1080i from what most so-called "geeks" say, but now that I read this, everything makes so much more sense.

I love reading the responses, because now it’s so obvious how people are tripped up on this issue. Example:

"Rendering 1080i means you render exactly 1/2 of the full frame pixels each time (alternating between odd and even rows.) This means 1080i requires calculating exactly 50% of the pixels for 1080p."

^^^…but the problem is those even and odd lines. You DO render half the pixels… but you have to do it twice. Seems so astoundingly simple now.

The real issue that I feel comes up is still framerates versus the human eye, though. Unless this is also mistaken, I believe the chief difference in the "feel" of interlaced versus progressive is the classic debate about TV screens versus PC monitors. A TV screen, with interlacing, can show an incredibly fluid (if less clear) image at maybe 24 frames per second. But a computer monitor could run at 60+ and seem relatively jerky, even with superior picture, because monitors tend to draw in progressive (again, maybe I’m off- this debate leaves me challenging my basic notions on everything here).

Doesn’t this still mean that 1080p has to render higher framerates for smooth action compared to similar effect at 1080i? (yes, I realize there’s more to TV and film smoothness than just interlacing alone, but I thought the effect was still non-negligible).
Olrac

GTHD is underwhelming? Cop yourself on. Sony must be doing a good job marketing this point if you’re STILL posting about this. Last time you came off looking pretty bad, and I doubt this will work out much better.
Pjotr

"Given that PS3 has about the same graphical horsepower of the Xbox 360 (less, say some sources) this is a rather hopeful claim. Do you have any reason to believe that PS3 can handle 1920×1080 better than Xbox 360, or is this just based on Sony’s unsubtantiated bragging."

Again, most games on Xbox 360 seem to struggle to reach a stable 30fps at 720p. And this is a year after the release.

The fact that devs are letting run games succesfully at 1080p on an unreleased console gives the impression that there is a difference. Wether it is the raw power, ease of use of the hardware or even the quality of the dev, I don’t know.
∞

Games and systems already are out that support 1080-and-up resolutions (hmmm, playing Quake 4 on a Mac Pro with a 30" Cinema Display…).
Nitz

haha, MS and it’s yes-men are pathetic, scrambling to fling mud at sony in the midst of their Xbox 360 meltdown (litterally and fiquartively, what’s the defect rate on those things, 25%?).
Manya47

I’m still wondering why my SD plasma can display 1080i better than 480p. If you were to see it, you would understand. The picture is much clearer. 720p doesn’t look as good though.
wonderboy

yeah…lets talk about the ps3 instead of the xbox3…….60

microsoft sucks
Olrac

"Given that PS3 has about the same graphical horsepower of the Xbox 360 (less, say some sources) this is a rather hopeful claim. Do you have any reason to believe that PS3 can handle 1920×1080 better than Xbox 360, or is this just based on Sony’s unsubtantiated bragging."

Tiling is going to absolutely suck for higher resolutions aka 1080p. Some devs have been having enough trouble hitting 720p thanks to its quirks! I even recall Xenos’s designer admitting that ATi’s contemporary non-eDram based PC GPUs would likely have the edge over Xenos for high resolutions like 1600×1200 (which is the same number of pixels as 1080p, funnily enough). That comment didn’t seem signifcant at the time, but it takes on whole new relevancy now given how things are turning out.

I think you definitely will see good looking 1080p native games on 360, but I wonder if you’ll see them as frequently as you will on PS3.
TCampbell66

Many doctors and those not caught up in the hype of misleading information on this subject have stated the human eye can only visually intake 30 frames per second, rendering the whole hype of forcing 1080p in games pointless. The point of this article is 720p is a neutral zone for game developers right now if they want the least bit of overall quality downgrading. By raising it to 1080p you risk lots of other graphical problems arising just over the trade off of making a car or game character itself look better against the overall degraded quality game. 1080p is hype, 60fps is hype… all hype for those with disposable income to get suckered into because in their mindset more or a higher count must mean better, in the case of games right now it is not. Any company forcing this groundless 1080p spec to unknowledgable brand loyalists are only instilling inaccurate fuel for blind fanboys to use against their competition. Like the guy said above earlier, there is a sucker born every minute.
eawil2000

For me being a tekkie I’ve bee missing a lot of key pieces of information out of the PS3 / Xbox 360 1080p "debate". From what I can gather all 360 games are rendered internally on the 360 in 720p. Apparently developers can render in 1080i if they so choose, but for the most part they’re at 720. The 360 then scales the 720p image to whatever the user wants.

There has been speculation that the 360 when outputing 1080i is actually scaling DOWN the 720p image to a 540p image. The speculation is based upon the resolutions that the VGA adapter allows you to output. The argument is that if the video card translated 720p to 1080i then there should be some sort of 1080p (even if it isn’t 60Hz) available for output via VGA.

So when I heard Peter Moore announce that the 360 was going to be able to do native 1080p, this was good news. Now, after reading this article, I am a little confused. The 1080p output won’t be doing anything different? If so, why doesn’t the VGA output allow for 1080p as it stands right now?

There is certainly a trade off between 1080p and 720p in terms of graphical fidelity. You have only so much power you can use. But what many tekkies like myself have been happy about, is that from the start Sony has been very forthcoming with the information (and really the only part of the console that has had clarity) that the PS3 renders internally at 1080p and doesn’t do 540p tricks, or upscales 720p, or whatever (although if a developer renders its games at 720p the PS3 will upconvert to 1080p).

I think that this is the area that this is the point many people are still trying to get clarification on.
eawil2000

TCampbell66, I don’t know if I would go so far as to say 1080p and 60 fps is "hype". If you can get 1920×1080 @ 60Hz to have the same graphical fidelity as 1280×720 @ 60Hz then that’s not hype. The point made, which I agree with, is that to get the increase in pixels you have to take away from something else since you only have a fixed amount of power available to use.

As far as why 60Hz is better than 30Hz, it is more based upon perception. Life moves at a rate much, much grater than 60Hz. That’s why movement in life seems, well… lifelike; even though our brain can only really process the visual signal from our eyes at 30Hz. The same thing happens for computer systems and TV’s. The system internally calculates a faster than 30Hz motion in order to give the system a more fluid motion. You don’t actually see the missing frames, but it looks less jerky and more fluid.

Similarly 1080i is not the same as 1080p all other things being equal. In a 1080i signal you can get tear effects when you move the camera too quickly (one part of the image is looking at the new camera position, and the other part of the image is looking at the old camera position). A 1080p image doesn’t get tear effects.
bob saget

the ps3 fanboys are going bonkers lolers
Olrac

"Many doctors and those not caught up in the hype of misleading information on this subject have stated the human eye can only visually intake 30 frames per second, rendering the whole hype of forcing 1080p in games pointless."

I’m not sure what resolution has to do with frames per second, but that’s nonsense. The human eye can, depending on conditions, differentiate between framerates well beyond 30fps.

The point you seem to miss in the rest of your post is that not every game is using all the power of the system, and thus can afford to go to 1080p without compromise. We’re seeing that in games like Virtua Tennis 3 and Ridge Racer 7, which are 1080p/60 and look better than their 720p equivalents on 360. Where’s the sacrifice there, hmm? There is none, because these games fall so comfortably under the systems capability than 1080p is not a problem. If it were a problem, I’m sure the developers would not use the resolution, and would stick to 720p – IT IS AN OPTION. This might be worth debating if Sony was forcing developers to use 1080p, but they’re not. This is as pointless as debating the merits of any other optional choice a developer could make in the development of a game – for example, trading off CPU power for one area versus another in a game. The only reason Ozymandias and MS keep trying to cast a negative pall over this particular one is because they’re lagging their competition here.

Don’t you see? They’re trying to stir ‘technical debate’ purely to serve a marketing agenda, and they’re using us as pawns in that. It’s crazy.
TCampbell66

eawil2000 – Being a game developer myself my experienced perception is that everything you stated were contradictory oxy morons in your explanation. Which is surprising to see from a "trekkie", but then that line of logic would render you enjoying those god aweful special editions they are making with the original Star Trek series right now. lol No one specific resolution over the other causes tearing unless the developer allows it as a part of the resolution trade off – it’s hype and your speech reveals you’ve bought into it. :)
TCampbell66

Olrac – You mostly stated the same thing I did but in a different way. I agree this is all a marketing spin to the gullible. I mean some of them are posting here.
byron miller

I have 2 lcd – 720p displays (native) and a projector that i run at 720p and sometimes 1080i.

On my LCD’s which are all 32" – i would never want to run 1080p if the focus of the game was to show more detail because of viewing distance and comfort. It wouldn’t be pleasing to the eye. Its not like computers where your sitting 3 feet away at most, i’m at least 8 feet away from my tv’s and i’m even further from my projector! I like fluid colors, smooth textures and smooth graphics – not necessarily super fine resolution of immediate images that would look more detailed. I think working on drawing distance, pop in, tearing is more important than trying to push the detail of a game at a higher resolution as the whole point of 1080i/1080p is moot since to most people is 1920×1080 vs 1280×720 no If ands or P’s.

On my projector with a 105" screen i can afford the resolution because i’m blowing it up and sitting further back.. so its no value to mee adn if i wanted pixel perfect resolution on an 105" screen we are talking resolutions MUCH higher than 1080p!

so yeah, if your PS3 or Xbox is connected to a computer monitor then 1080p may make a difference if your looking for the detail and resolution afforded, otherwise if your console is its home in front of your tv, what difference will this actually make? I’m not looking for that level of detail when i’m sitting in my couch.

Resolution matters – but used in the right way. HD/720 looks sharp because its the perfect mix of "resolution" and "clarity" that 1080p COULD do – but would the resolution actually lead to better games or just eye strain of trying to appear better for something that isn’t designed for 2-3 foot viewing distance?

believe me, i like my WXGA resolution on my laptop (and larger) but for many people its too small even on a 21.5 inch matched monitor.
hg

Ok, so 720p is better than 1080p…

But, following your logic, wouldn’t you have to conclude that 480p is even better than 720p, because you can show more detail and run more complex pixel shaders, and 640×480 with 4x AA will generally look better than 1280×720 with no anti-aliasing (there are more total samples).

Am I right?
Casey

720p@60fps provides more video data than 1080i@60fps, and even more than 1080p@30fps. However any computer gamer will tell you higher resolutions give a better (sharper) image. Now, this notion that 1080p reduces graphically fidelity… well thats only true if you dont have the horsepower to properly render at 1080p. With a good graphics subsystem you can do FSAA@1080p no prob, and anything else you can do at 720p. I think what were being told here, in a roundabout way, is that the ATI card in our 360s doesn’t have the power. Well, ok, whatever… but dont tell us you HAVE to give up fidelity at 1080p. You may HAVE to with the 360, but not with a powerful enough system. Not that the PS3 will be any more powerful, an nvidia 7800 part (PS3 card of choice) is no more powerful than the 360s ATI chip (maybe even less so, since its sans unified shaders). And now I’ll throw it out there: Doesn’t the ati chip have 10mb of superfast edram to offload the work of AA? And it can’t muster AA@1080p? wtf?
http://www.gizmodo.com/gadgets/home-entertainment/1080p-gaming-not-what-it-seems-209311.php Gizmodo

RE: Clarifying Thoughts on High Definition Game Rendering

There is no doubt that 1080p is the holy grail of high definition, which is exactly why Sony has pursued that benchmark with such enthusiasm. But exactly how hard is 1080p to render for video game consoles? Here are some…
Sulphuric Acid

To clarify, the game developer chooses the size of the buffer be it 720 or 1080 – IT DOES NOT deal with interlacing.

Then, the display chip in the Xbox 360 takes this image and converts it to whatever resolution and interlacing you have picked in the dashboard.
Defender of 087

So all in all 720P>1080P for Gaming better performance, Effects, some what better Visuals at 720P. I think most PC gamers already knew this! But thoes fanboys got to lern the hardway thats life for ya.
eawil2000

TCampbell66, being an aerospace engineer by trade I am not a "trekkie", I’m a tekkie (what I originally put down). ;-)

I don’t see how my post is an "oxy moron", your original post was based on two foundations: 1) 1080p doesn’t look better due to system power constraints, and 2) a 60 Hz signal doesn’t look any different than a 30Hz signal.

I agree with point #1.. up to a point. *IF* the developer is using all the system resources to its full potential at 720p, then, yes 1080p will look worse because you have to get rid of effects to get the higher resolution. But, as I was pointing out, *IF* you have the same fidelity of graphics availble at 1080p as you do at 720p then the 1080p will look better.

I disagree with your second argument. Frame-rate matters; as a developer I’m surprised you don’t agree. A 30 fps signal stutters a lot more than a 60 fps signal. The fact that you’re actually transmitting 60 fps is all the better.

I also take to task your implied statement that at 30 Hz 1080p is fine. 30Hz at 1080p is *essentially* 1080i. The interlacing causes tear effects which are quite noticable whe playing a fast paced game, or watching a fast paced movie.

Those were the bases of my argument. I personally fail to see how those are oxymorons.
eawil2000

To play devil’s advocate: if it is true that 720p>1080p due to system power, then 480p>720p…. That’s Nintendo’s argument.
jothaxe

"I thought the article addressed this. It’s called field rendering and it causes problems, like increased flicker. It also requires a rock solid 60 fps, which is difficult on modern games because of their complexity. Yes, games could do field rendering. Yes, it helps the performance problems of 1080 resolutions. But, since it makes games look worse (flicker really *sucks*) I really doubt it is a good idea."

Yes I saw this in the article. I agree that flicker sucks. It is always bad to have less pixels and 1080i can cut the pixel (render) count in half. This is good for speed and bad for quality. Whether or not the trade-off is worth is it simply going to depend on the application. My point is that its unfair to say that 1080p rendering is 1.0x times as hard as 1080i. It can be done with 1/2 the rendering as the expense of quality.
Transfix

Taken from one of my HT sites. Plain and simple

"Is 720p vs 1080i worth being concerned about? Yes and no. If you’re a consumer looking for a new TV, you can happily ignore the 720p vs 1080i debate because every TV which is described as HDTV or HDTV Ready is required to support both formats.

NOTE: You should be aware though that lots of TVs which support 1080i have fewer than 1080 lines and so scale the 1080 signal down. That’s not a huge issue as even scaled down 1080i is far ahead of a regular NTSC signal. It is worth bearing in mind that more expensive HDTVs tend to have better scalers than cheaper ones, and this may be an issue.

However, for broadcasters it’s a live issue. Should they broadcast 1080 lines of interlaced video or 720 lines of progressive scan? They could just broadcast two signals, one in each format, but that would use up a huge chunk of bandwidth and be hugely expensive for very little gain.

To answer the question, it’s important to understand the difference between 720p vs 1080i. A 720p signal is made up of 720 horizontal lines. Each frame is displayed in its entirety on-screen for 1/30th of a second. This is know as progressive scan (hence the ‘p’)The quality is like watching 30 photographic images a second on TV. A 1080i signal comprises 1080 horizontal lines but all the lines are not displayed on-screen simultaneously. Instead, they are interlaced (hence the ‘i’), ie every other lines is displayed for 1/60th of a second and then the alternate lines are displayed for 1/60th of a second. So, the frame rate is still 30 frames per second, but each frame is split into two fields, which your brain then puts together subconsciously.

Most of the time interlacing works fine, but for fast moving images, such as sports like baseball and hockey it can cause problems which manifest themselves as a ‘stepping’ effect on-screen. Progressive scan signals don’t have this problem and so are better suited to sports.

ESPN puts it like this: ‘Progressive scan technology produces better images for the fast moving orientation of sports television. Simply put, with 104 mph fastballs in baseball and 120 mph shots on goal in hockey, the line-by-line basis of progressive scan technology better captures the inherent fast action of sports. For ESPN, progressive scan technology makes perfect sense.’

Clarifying Thoughts on High Definition Game Rendering

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