What Does 1080p Mean For Game Developers?

[dafloppyone]

Microsoft's game dev blog Ozymandias has some thoughts and stats on High Definition Game Rendering:

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 1920x1080 compared to 1280x720
• 55.5%: that's how much less time you have to spend on each pixel when rendering 1920x1080 compared to 1280x720-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.
• 1280x720 with 4x AA will generally look better than 1920x1080 with no anti-aliasing (there are more total samples).

Any game could be made to run at 1920x1080. 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 1280x720-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. ​