[whatwg] [canvas] request for {create, get, put}ImageDataHD and ctx.backingStorePixelRatio
Darin Fisher
darin at chromium.org
Mon Apr 23 10:33:01 PDT 2012
On Tue, Apr 17, 2012 at 9:12 PM, Boris Zbarsky <bzbarsky at mit.edu> wrote:
> On 4/17/12 6:32 PM, Darin Fisher wrote:
>
>> In Chrome at least, getImageData() doesn't actually block to fetch pixels.
>> The thread is only blocked when the first dereference of the pixel buffer
>> occurs.
>>
>
> How does that interact with paints that happen after the getImageData
> call? Or is the point that you send off an async request for a pixel
> snapshot but don't block on it returning until someone tries to reach into
> the pixel buffer?
>
>
To answer your second question: Yes.
I think the implication for the first question is that you would get back a
snapshot of what the pixel data should have been when you called
getImageData.
-Darin
More information about the whatwg
mailing list