Working hand-in-hand with Microsoft's performance aspirations for IE 9 is a surprising browser capability: GPU-backed hardware acceleration. "This is the coolest but least understood aspect of IE 9 we announced," Hachamovitch said. "We've moved the IE rendering engine from GDI to DirectX."
There are two benefits to this approach. First, the web doesn't have to be rewritten to take advantage of this functionality, as it's just provided by using IE 9. And second, web developers can now seamlessly take advantage of all of the benefits associated with PC hardware advancements that have happened over the past few years. The GPU is no longer just used for games, 3D user interfaces, and other graphics-intensive applications.
The confusion here relates to expectations about hardware-accelerated graphics. When some people hear such a thing, they automatically think about gaming. But IE 9's hardware acceleration has nothing to do with gaming. Instead, it's all about performance and fidelity. The browser just performs better, of course. But it also makes everything--especially text--look better.
The performance stuff is pretty obvious: Navigating around a Bing map, for example, you can readily see that IE 9 renders far more quickly--and with much less CPU overhead--when GPU acceleration is enabled. But the overall fidelity improvements were, to me at least, unexpected. Text rendered through the GPU with Direct2D exhibits none of the jaggies you see with standard, GDI-rendered text. And the effect is especially impressive when you zoom in and out of textual displays. It's like the difference between ClearType- and non-ClearType-based text, except this time, sub-pixel rendering is just the starting point.
"Direct2D finds more pixels on the edges and smoothes out jaggies," Hachamovitch told me. "It provides smoother animations as well. The performance is amazing. Web sites get better in IE on Windows."
Some have also confused this functionality with WebGL or other standards-based rendering schemes. These people are missing the point, Hachamovitch said. "It's just a subsystem. This means that whatever others do on top of the browser will have better performance and clarity as well."
Hachamovitch also noted that other browser makers have only done some minimal, edgy work around hardware acceleration. The reason is simple: Its hard work. "Games utilize this technology, of course, but let's face it, games don't print. We have to make sure IE works as before with hardware accelerated rendering. You want your boarding pass to just print. You want ActiveX controls and Flash video to just work. That's what we're working on."
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