[whatwg] [canvas] inner shadows

Glenn Maynard glenn at zewt.org
Fri Nov 23 15:47:06 PST 2012

On Fri, Sep 21, 2012 at 7:49 PM, Rik Cabanier <cabanier at gmail.com> wrote:

> With both types of shadow, you take the shape of the element and calculate
> the blur image.
> With an outer shadow, you take the result of the blur and composite it.
> After this, you composite the original shape.
> With an inner shadow, you draw the shape first followed by the blur image.
> Importantly, the blur image also needs to clipped by the shape before it is
> composited.

Also, the blurred image's alpha is inverted.

Glenn Maynard

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