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Re: [css4-color] 4 Parameters in RGB() and HSL()

From: Marat Tanalin | tanalin.com <mtanalin@yandex.ru>
Date: Wed, 25 Jan 2012 18:38:11 +0400
To: Christoph Päper <christoph.paeper@crissov.de>
Cc: www-style@w3.org
Message-Id: <289431327502291@web61.yandex.ru>
25.01.2012, 18:33, "Marat Tanalin | tanalin.com" <mtanalin@yandex.ru>:
> 25.01.2012, 18:11, "Christoph Päper" <christoph.paeper@crissov.de>:
>
>>  Several pseudo functions accept different numbers of parameters, the rightmost parameters are then optional, original ones don’t change their meaning. In CSS3: Color rgba() and hsla() have been added without taking advantage of this polymorphous capability. They also have been criticized for always denoting the alpha value as a number in the range 0.0–1.0, not as a percentage.
>>
>>  Could we therefore make
>>
>>    rgb(100%, 80%, 60%, 40%)
>>    hsl(300deg, 60%, 40%, 20%)
>>    rgb(255, 0, 64, 127)
>>
>>  valid in Level 4?
>
> Indeed, separate rgba() function looks redundant since we could just add fourth parameter to rgb().
>
> Percentage values as allowed alternative for 0.0-1.0 decimal for alpha opacity look nice too. Not sure such notation is appropriate in place of 0-255 numbers, though.

And, of course, percentage value should always end with "%" character, otherwise there would be ambiguity for "1" value (and probably even backward-incompatibility with values greater or equal to 1):

    rgb(255, 0, 64, 1%) /* 1% */
    rgb(255, 0, 64, 1)  /* 100% */
Received on Wednesday, 25 January 2012 14:38:44 GMT

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