On Mon, 13 Feb 2012 14:17:28 -0000, Boris Zbarsky <[email protected]> wrote:
This is a difficult optimization to make. You can only do it for images
that have a height and width specified in the markup, and worse yet it
leads to pretty bad flicker as the user scrolls (because network
roundtrip times are measured in hundreds of milliseconds to seconds). So
doing this by default is not likely to happen. Having a page opt into
it is a different story, though.
Well, UAs would fetch the images to be displayed first first, and then
prefetch images until they have more than a screenful of undisplayed
content loaded. But yes, fast scrolling would break this. Not even knowing
the rough size of images before fetching them makes them hard to lay out
until they have been downloaded.
--
-,Bjartur
