[whatwg] Adding blending to the canvas API

[David Dailey]

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