Re: [css3-background] blending on 'box-shadow' and 'text-shadow'

On Apr 11, 2012, at 9:10 AM, Rik Cabanier wrote:

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> On Wed, Apr 11, 2012 at 8:50 AM, Brad Kemper <brad.kemper@gmail.com> wrote:
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> On Apr 10, 2012, at 5:51 PM, Lea Verou <leaverou@gmail.com> wrote:
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> > I think this problem should be solved more generically, rather than adding keywords to random properties. For example, the `difference` blending mode could be used on text color to make it more legible regardless of background. Or, blending modes on borders and/or backgrounds could produce quite interesting effects. They could also replace the `invert` keyword on `outline`.
> > Maybe a function that can be used in place of any <color> value?
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> That was my first thought. Maybe even just extending rgba() and hsla() to be able to do this sort of thing: rgba(255,255,0,1,m) to multiply, and rgba(255,255,0,1,s) to screen.
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> Doing it that way forces people to use the 'rgba' notation so they won't be able to do 'color: red screen'

You wouldn't be able to do that as part of any <color> anyway, because the space would confuse shorthand properties that use a space. Maybe if there was a new separator that wasn't used elsewhere it would work, like 'background: red•screen'.

> Another issue is that this implies that you can use it in gradient color stops which would be very strange.

True. Same issue if you use 'red screen' or 'red•screen' in a gradient. Or if you use any syntax of color mode in an animation or transition to go between two color modes. You'd have to say that there is a sharp cutoff midway between any two color modes.