On Wed, 9 Jan 2013, James Robinson wrote: > On Wed, Jan 9, 2013 at 11:59 AM, Ian Hickson <i...@hixie.ch> wrote: > > On Wed, 9 Jan 2013, Stephen White wrote: > > > > > > > > Right now by 2d canvases are effectively single buffered. At the > > > > appropriate time a copy of the canvas is made and passed to the > > > > compositor. This copy is slow, especially on mobile. > > > > > > Currently, to lower the VRAM footprint and improve performance, we > > > don't do a copy in 2d canvas. We temporarily transfer ownership of > > > the texture to the compositor at commit time, and block the renderer > > > until the composite is complete. That may change, however. > > > > Good to know, thanks. Should this change, or should there be a desire > > for a mode where it looks like after the commit the buffer is cleared, > > please do let me know. > > We (chromium) would really appreciate a way for the author to express > clear-after-commit. I think this would match up with what authors > frequently want, since many canvas pages clear the canvas at the start > of the next frame anyway, but allow for more flexibility and > optimizations in our implementation.
Noted: http://wiki.whatwg.org/wiki/New_Features_Awaiting_Implementation_Interest -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'