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Re: [CSS3 Color] Percentages in Alpha Value etc.

From: Laurens Holst <lholst@students.cs.uu.nl>
Date: Wed, 13 Jul 2005 20:13:13 +0200
Message-ID: <42D559B9.2050106@students.cs.uu.nl>
To: Matthew Raymond <mattraymond@earthlink.net>
Cc: Christoph Päper <christoph.paeper@tu-clausthal.de>, www-style@w3.org

Matthew Raymond wrote:

>> There also seems to be little reason not to allow alpha values in the 
>> short and long hexadecimal format, they would just have to gain a digit:
>> #0000--#FFFF and #00000000--#FFFFFFFF. After all, from my experience, 
>> this is the most popular form for specifying colors out there in 
>> stylesheets. I will not go as far as suggesting, that something like 
>> "rgb(#0, #F, #0F)" (= "#00FF0F" = "rgb(0, 255, 15)") should be allowed.
Nice idea, too.

>    Okay, sounds fine. Or perhaps we could do something to make it a 
> bit more clear like "##FFFFFFFF" or "#FFFFFF-FF".

Don’t see why. Red, green and blue aren’t distinguished from another 
either, why should the opacity value be different. And the ## seems to 
unnecessarily complicate things. Neither #FFFFFFFF nor the shorthand 
#FFFF will conflict with anything else.

>    There's still the backwards compatibility problem in that "1" can 
> be "1.0" in the current spec. Perhaps we'd be better off dropping 
> float and making the ranges for alpha 0-255 and 0%-100%, just like the 
> values in rgb().

Personally, I’d prefer 0...255, 0%...100% and 0.0...1.0 to apply to both 
the rgb values and the alpha channel. That makes it consistent, and I 
like the thought of specifying colour values in the 0-1 range, although 
in practice few people will probably use that.


Ushiko-san! Kimi wa doushite, Ushiko-san!!
Laurens Holst, student, university of Utrecht, the Netherlands.
Website: www.grauw.nl. Backbase employee; www.backbase.com.
Received on Wednesday, 13 July 2005 18:13:15 UTC

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