[whatwg] Adding blending to the canvas API

Rik Cabanier cabanier at gmail.com
Sat Apr 14 20:27:09 PDT 2012

ah, yes. You are correct! I didn't see the different blending modes.

Reading the SVG filter spec, it is unclear what ctm the inputs of the
filters should be in.
Chrome and Firefox ignore it (like the spec seems to imply) while opera
keeps it. That should really be fixed...


On Sat, Apr 14, 2012 at 4:41 AM, David Dailey <ddailey at zoominternet.net>wrote:

> Rik wrote:
> >Not having an implementation of BackgroundImage makes blending in SVG very
> difficult.
> >I'm unsure why you think that specifying a magenta color will change the
> color model to subtractive. As far as I know, the renderer is always
> >computing in RGB.
> No I don't think that the color model in the browser changes. Rather the
> Venn diagrams as drawn using mode=screen vs mode=multiply depict (in the
> proper browser) the traditional diagrams of those models.
> http://cs.sru.edu/~ddailey/svg/V9.svg as viewed in Opera corresponds to
> those diagrams usually hand-painted in texts (or broken in to separate
> paths
> in Wikipedia at http://en.wikipedia.org/wiki/Subtractive_color -- hence
> undermining accessibility).
> Cheers
> David

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