On Mon, Oct 21, 2013 at 6:08 PM, Kenneth Russell <k...@google.com> wrote:
> > Using ImageBitmap for this has a lot of issues. It requires > synchronizing > > with scripts in the UI thread. > > This isn't difficult, and amounts to a few additional lines of code in > the main thread's onmessage handler. > Synchronization with the UI thread isn't bad because it's difficult. Avoiding synchronization with the main thread has been raised as a desirable goal: http://lists.w3.org/Archives/Public/public-whatwg-archive/2013Oct/0152.html"including that it isn't possible to render from a worker without synchronizing with the main thread." (My previous comments on this are here: http://www.mail-archive.com/whatwg@lists.whatwg.org/msg35959.html) > The ImageBitmap style proposal has another significant advantage in > that it allows a single canvas context to present results in multiple > output regions on the page. > You can do that. You just create a WorkerCanvas for each canvas you want to present to, hand them to the worker, then attachToCanvas in the worker to switch from canvas to canvas. (That's orthogonal to explicitpresent.) > This sort of resource exhaustion is certainly possible, but I view > this downside as smaller than the upside of addressing both of the > above use cases. > I can only find one thing above that you might be referring to as a use case (the one I replied to immediately above). What was the other? -- Glenn Maynard
