Re: [whatwg] High-density canvases

On Wed, Apr 15, 2015 at 1:46 PM, Dean Jackson <dino@apple.com> wrote:
>
> On 16 Apr 2015, at 6:42 am, Elliott Sprehn <esprehn@chromium.org> wrote:
>
> 3. Accessing rendered pixel size is layout-inducing. To avoid layout
>>
>> thrashing, we should consider making this an asynchronous getter (e.g.
>> asyncGetBoundignClientRect). This would also prevent renderedsizechanged
>> events from firing from within the evaluation of the
>> renderedPixelWidth/Height
>> attributes, which is weird.
>
>
> renderedsizechanged feels like it's related to the general per element
> resize event problem. It'd be unfortunate to add an event to the browser
> specifically for canvas instead of solving the general problem. In that case
> authors will start resorting to hacks where they insert canvases into the
> page to listen for resizes (we've seen this with other events like
> overflowchanged).
>
> Perhaps we should add per element resize events and spec that they fire
> after the layout, but before the paint, during normal frame creation. That
> does mean you can cause an infinite loop if your resize handler keeps
> mutating the page, but there's so many other ways to cause that already.
>
>
> +1

If that's a viable option let's do that. It would solve many
longstanding problems.

-Ken

Received on Thursday, 16 April 2015 05:23:09 UTC