Re: [css-compositing] blending in canvas

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
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
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?


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

> On Wed, Nov 14, 2012 at 10:48 AM, Rik Cabanier <> 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 UTC