[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


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