- From: Simon Sapin <simon.sapin@exyr.org>
- Date: Thu, 09 May 2013 15:06:08 +0200
- To: "Tab Atkins Jr." <jackalmage@gmail.com>
- CC: Sebastian Zartner <sebastianzartner@gmail.com>, Jake Archibald <jaffathecake@gmail.com>, Lea Verou <lea@w3.org>, Šime Vidas <sime.vidas@gmail.com>, www-style list <www-style@w3.org>
Le 08/05/2013 17:17, Tab Atkins Jr. a écrit :
> On Wed, May 8, 2013 at 3:52 AM, Sebastian Zartner
> <sebastianzartner@gmail.com> wrote:
>> Since different kinds of color values are involved in these examples, using
>> rgba() doesn't make sense here. alpha() seems more logical to me.
>
> Agreed. I'm thinking maybe a pair of functions for each component,
> set-*() and adjust-*(), for either overriding the given channel or
> adjusting it up or down. Hmm, though, there's argument for both
> adjusting by a set amount, and by a percentage amount, at least for
> some channels. I'll look into what the preprocessors do, precisely.
I don’t have much practice using such functions, but setting/adjusting
individual color channels seems more useful in HSL space than RGB.
As to alpha, I think that multiplying is the obvious thing to do. For
example, the used alpha here would be 0.3:
.foo {
var-bar: rgba(255, 0, 128, 0.6);
background: alpha(var(bar), 0.5);
}
This simplifies to "set" if the first argument’s alpha channel is 1. I’m
not sure if the second argument or the result should be clamped to 0..1.
Cheers,
--
Simon Sapin
Received on Thursday, 9 May 2013 13:06:31 UTC