Windows 8 ready for iPad-beating resolutions
Microsoft claims its adapting Windows 8’s graphics to cope with tablet screens with resolutions greater than that of the new iPad.
The third-generation iPad’s “Retina” display boasts an industry-leading resolution of 1,536 x 2,048, giving it a pixel density of 246ppi. But in a post on the Building Windows 8 blog, Microsoft says it’s preparing its new operating system for 11.6in tablets with a resolution of 2,560 x 1,440, or 253dpi.
If all apps were scaled to fit, users wouldn’t be able to see more email messages on their 23in 1,920 x 1,080 screen
The blog post explains how Microsoft will scale graphics in Windows 8 according to screen resolution and size, particularly to avoid the problem of icons becoming to small to prod on high-density screens.
“For those who buy these higher pixel-density screens, we want to ensure that their apps, text, and images will look both beautiful and usable on these devices,” writes Microsoft’s senior program manager, David Washington.
“Early on, we explored continuous scaling to the pixel density, which would maintain the size of an object in inches, but we found that most apps use bitmap images, which could look blurry when scaled up or down to an unpredictable size,” writes Washington of a problem that has become apparent on the new iPad, when running apps designed for previous generation devices. “Instead, Windows 8 uses predictable scale percentages to ensure that Windows will look great on these devices.”
Microsoft says it will use three scale percentages in Windows 8: 100%, 140% for HD tablets and 180% for the so-called quad-XGA tablets running at 2,560 x 1,440.
“Each scale percentage was chosen to ensure that a layout that was designed for 100% 1,366 x 768 tablets has content that is the same physical size and the same layout on 140% HD tablets or 180% quad-XGA tablets,” Washington writes.
Microsoft claims the predefined scales will allow developers to provide images for each percentage, thus avoiding blur or artefacts created by stretching images. Windows 8 also offers native support for vector graphics, so any images provided as SVG or XAML art will automatically scale without blurring.
Microsoft says it will give Metro app developers the choice of using adaptive layouts – where more content is displayed to those on higher resolution screens – or scaling to fit.
“We believe it is important for app developers to be able to choose which layout technique — adaptive or scaled to fit — makes the most sense for them, depending on their content and their workflow,” writes Washington.
“If all apps were adaptive, it would be difficult to build a game-like rendered UI that fills a 23in 1,920 x 1,080 screen without huge empty margins. On the other hand, if all apps were scaled to fit, users wouldn’t be able to see more email messages on their 23in 1,920 x 1,080 screen.
“We believe that our solution strikes the right balance, and provides developers with the choice and tools to optimise their apps for different screens based on the scenarios that are most important for them.”
However, the blog post doesn’t reveal how Microsoft will adapt displays for traditional Windows applications running on the old desktop.