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Bungie Explains Halo 3's Resolution
For some folks artisitic merit or financial success of Halo 3 isn't what's really important: it's about how many pixels are on the screen. After there were some complaints about the 'truth' of the game's HD nature Bungie posted a missive on their site clarifying the output process for Halo 3's visuals. "Halo 3 uses not one, but two frame buffers - both of which render at 1152x640 pixels. The reason we chose this slightly unorthodox resolution and this very complex use of two buffers is simple enough to see - lighting. We wanted to preserve as much dynamic range as possible - so we use one for the high dynamic range and one for the low dynamic range values. Both are combined to create the finished on screen image. This ability to display a full range of HDR ... gives our scenes ... a steady and smooth frame rate, which in the end was far more important to us than the ability to display a few extra pixels."
I was expecting an article about how the game ends, and was prepared to make an epic post about a bunch of dots...
The article stole my joke!
Those who care about this can wait for the PC version which I'm sure will allow you to pump the resolution to 1600x1200 (or possibly more by editing the .ini files) and zip along in glorious DirectX 10 goodness with their $500 video cards. Of course, by the time it comes out for the PC it will look dated (like Halo 2) and the people with the high-end rigs will be playing something else.
But if you really want it, it's coming.
All the complaints about Halo 3's resolution reminds me of all the "pixel peeping" that goes on when it comes to digital cameras. Everyone gets hung up on tech specs to the point that they stop looking at the image in question.
Halo 3 looks nice, and plays great. That's all that matters to me. I'm certainly willing to forgo some extra pixels in favor of a smoother experience.
Er... less ignorance, more knowledge plz. These frame buffers are on TOP of the double (or maybe even triple) buffering that is already done from frame-swapping. The whole idea is that 32-bit screen buffers do not have enough range to properly account for HDR lighting (i.e. that nice effect where your eyes take time to adjust after coming out of a dark tunnel, and also the real way to do light blooms). So in essence what they're doing is two 32-bit buffers to simulate a very large 64-bit buffer, where each pixel has 64 bits of range. In total they would need to have at least 4 of these to account for the double buffering.
In an ideal world I should just be able to tell the machine to give me 64-bit color, but our hardware isn't quite there yet (almost).
The Xbox 360 will display every game at whatever output you choose. On your cousin's elite, he's apparently set it to 1080p. That doesn't mean that games change how they render. It just means that when the framebuffer passes through the on-board scaler chip prior to heading out the the TV, the image is upscaled to 1080p rather than 720p or whatever else you may choose. The two games you mentioned, Gears and Bioshock, actually render internally at 720p (or more precisely, 1280x720, since designations like "720p" don't make sense until the output is heading to a TV). Bungie made the decision to render at 1152x640 using a two-pass method (actually a two-buffer method) to render low-dynamic range and high-dynamic range lighting. The two buffers are then merged for the final picture. There's actually a Powerpoint on Bungie's HDR lighting method floating around the internets somewhere, if you feel like investigating why they did this. Anyway, the end result is mostly the same -- the 360's hardware scaler chip is quite good, and only the OCD pixel counters will ever notice that the game is natively rendered at 640p rather than 720p or 1080p.
History lesson: The graphics engine from Halo 1 was not re-used for Halo 2. It was re-used for Stubbs the Zombie (a game built by an ex-Bungie guy who which licensed the Halo 1 engine). The Halo 2 engine was all new. I haven't heard specifically whether or not the Halo 3 engine was again a new engine or if it was based on the Halo 2 engine, so for now I'll assume the latter.
As for not being able to handle double-buffered 1920x1080 resolutions, there are currently exactly two games on the Xbox 360 that render in 1080p -- Virtua Tennis 3 and some basketball game (NBA Street Homecourt, I think). It's also good to keep in mind that Microsoft has all but said that 720p is the sweet spot for Xbox 360 (HD movies and trailers on the marketplace are all encoded at 720p rather than 1080p, for example). The hardware scaler is capable enough to convert the image to your TV's native resolution without compromising image quality. Obviously an upscaled 1080p image will not be quite as good as a natively-rendered 1080p image, but if you're playing the game rather than counting pixels you're never going to notice.
How many enemies and physics-affected items are on-screen at one time in Gears or Bioshock? How large are the areas? Now compare that to Halo 3, where you can have 30+ enemies on-screen at one time, with hundreds of items strewn about being affected by physics, on maps with draw distances measured in kilometers. Making a game is all about trade-offs. If you're going for small-scale battles in confined areas (think Doom 3), you can optimize for graphics because you'll have more free GPU and CPU time. If you're going for large-scale battles in wide-open areas, you're probably going to sacrifice some visual quality in order to get the gameplay right. You can't do it all, and if you can then it means you weren't ambitious enough.
I'll see your three buffers and raise you an aloe strip!