https://bugs.webkit.org/show_bug.cgi?id=90375#c80
In the above link, Hin-Chung shows how to determine whether an image is actually painted. 2012/8/13 Maciej Stachowiak <m...@apple.com>: > I that case, starting async decoding at layout time makes sense if and only > if at layout to e you can predict what you will paint. I don't know enough > about our rendering to know of that is the case. > > - Maciej > > > > On Aug 12, 2012, at 5:34 PM, Peter Kasting <pkast...@chromium.org> wrote: > > On Sun, Aug 12, 2012 at 1:24 PM, Maciej Stachowiak <m...@apple.com> wrote: >> >> Why not start asynchronous decoding immediately as the image is loading, >> and synchronize at paint time? What is the benefit of waiting until layout >> time to start decoding the image data? > > > Uninformed guess (since I haven't touched the decoders in a while), but > currently we don't decode unless the image is actually painted, which helps > a ton on pages that are an enormous long string of images (common cases: > Boston Big Picture blog, various porn sites), since most of the images can > be decoded after initial layout, or not at all (if the user never scrolls > down enough). If we started decoding as images loaded I'd imagine we'd do > (possibly a lot of) extra work compared to today. > > PK > > > _______________________________________________ > webkit-dev mailing list > webkit-dev@lists.webkit.org > http://lists.webkit.org/mailman/listinfo/webkit-dev > _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org http://lists.webkit.org/mailman/listinfo/webkit-dev
