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[whatwg] createImageData -> new ImageData() ?

From: Robert O'Callahan <robert@ocallahan.org>
Date: Mon, 11 Feb 2008 11:35:16 +1300
Message-ID: <11e306600802101435u6a96ce39t9bbc2cd6e6d1616e@mail.gmail.com>
On Feb 10, 2008 11:14 PM, Anne van Kesteren <annevk at opera.com> wrote:

> That would mean that passing ImageData around between two <canvas>
> elements doesn't always work as expected. I think that's highly
> undesirable. Is there any implementation where we know this will the case?
>

Not yet, but in Gecko when we get around to implementing variable-resolution
canvas backing stores, I expect it would happen because different documents
--- even different documents that can reference each other --- can be zoomed
different amounts, which affects the device-pixels-per-CSS-pixel ratio we
use internally.

It's actually worse than that, because we respond to dynamic DPI changes
(due to zooming or changes in preferences; I'm not sure if we actually
support detection of hardware DPI changes, e.g. due to screen mode
switching, but we easily could). So we might want to dynamically rescale the
canvas backing store.

Rob
-- 
"He was pierced for our transgressions, he was crushed for our iniquities;
the punishment that brought us peace was upon him, and by his wounds we are
healed. We all, like sheep, have gone astray, each of us has turned to his
own way; and the LORD has laid on him the iniquity of us all." [Isaiah
53:5-6]
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