[whatwg] Enabling LCD Text and antialiasing in canvas

[Robert O'Callahan]

On Tue, Feb 19, 2013 at 12:01 PM, Stephen White <senorblanco at chromium.org>wrote:

> On Sat, Feb 16, 2013 at 4:09 AM, Robert O'Callahan <robert at ocallahan.org>wrote:
>
>> Not really true, you can just give up on the complex cases and draw
>> grayscale whenever you feel like it.
>>
>
> And leave the behaviour unspecified, I'm guessing?  Doesn't that least to
> inconsistent behaviour between browsers?  Even within one implementation,
> if you had content whose command stream varied over the maximum buffer
> length threshold, it'd toggle between subpixel and grayscale AA. Not sure
> if this is a case worth worrying about, but it does feel like it's exposing
> more of the implementation that one would like.
>

You could avoid toggling by disabling subpixel AA permanently if you're
forced over the buffer threshold.

I don't think we should try to specify exactly when subpixel AA happens.
There's huge variation across platforms and UAs already and it very rarely
matters for interop; when subpixel AA fails the site still works. I think
we should treat this as a quality-of-implementation issue, possibly
assisted by author hints.

Rob
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