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Re: [css-compositing] blending in canvas

From: Rik Cabanier <cabanier@gmail.com>
Date: Thu, 15 Nov 2012 14:36:48 -0800
Message-ID: <CAGN7qDDYqRvHBGZ+e0i-TNgZ2-Tcry7N5QherRpSo2=DFzynuQ@mail.gmail.com>
To: "Tab Atkins Jr." <jackalmage@gmail.com>
Cc: "public-fx@w3.org" <public-fx@w3.org>
Maciej still objects because he feels that this is a substantial difference
between CSS and Canvas.

I think we have a couple of choices:
1. Keep globalCompositeOperator for blending and compositing but collapses the
2 CSS properties into one that takes the same arguments as
globalCompositeOperator
2. Keep the 2 CSS properties but split the Canvas properties into
globalCompositeOperator and globalBlendOperator
3. Don't change anything and live with them being different.
4. Don't change anything but also define a new CSS shorthand that combines
blending and compositing. Canvas is compatible with this shorthand.

I'm unsure what approach we should take.
option 2 has the issue that we can't implement this correctly in the near
term.
option 1 has the issue that transitionable blending will be more confusing
in the future.
option 4 should cover all concerns but introduces yet another keyword.

Any comments?

Rik

On Wed, Nov 14, 2012 at 11:10 AM, Tab Atkins Jr. <jackalmage@gmail.com>wrote:

> On Wed, Nov 14, 2012 at 10:48 AM, Rik Cabanier <cabanier@gmail.com> wrote:
> > Good point!
> >
> > They are just strings, so we can later define it so you can say:
> > mycontext.globalCompositeOperator = "multiply,source-atop"
>
> I'd use a space-separated pair, but otherwise, yes.  ^_^
>
> ~TJ
>
Received on Thursday, 15 November 2012 22:37:16 GMT

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