W3C home > Mailing lists > Public > www-style@w3.org > November 2009

Re: [gradients] basics

From: Brendan Kenny <bckenny@gmail.com>
Date: Mon, 9 Nov 2009 03:48:14 -0600
Message-ID: <ab96c3ef0911090148g5fa7e918k44036cb16f9648fc@mail.gmail.com>
To: Andrew Fedoniouk <news@terrainformatica.com>
Cc: "Ph. Wittenbergh" <jk7r-obt@asahi-net.or.jp>, www-style List <www-style@w3.org>
On Mon, Nov 9, 2009 at 2:21 AM, Andrew Fedoniouk
<news@terrainformatica.com> wrote:
>
> ----- Original Message ----- From: "Ph. Wittenbergh"
> <jk7r-obt@asahi-net.or.jp>
> To: "www-style List" <www-style@w3.org>
> Cc: "Andrew Fedoniouk" <news@terrainformatica.com>
> Sent: Sunday, November 08, 2009 10:36 PM
> Subject: Re: [gradients] basics
>
>
>>
>> On Nov 9, 2009, at 3:24 PM, Andrew Fedoniouk wrote:
>>
>>> Ph. Wittenbergh wrote:
>>>>
>>>> On Nov 9, 2009, at 1:29 PM, Andrew Fedoniouk wrote:
>>>>>
>>>>> background: linear-gradient(magenta yellow), url(...)
>>>>>
>>>>> has no visual effect but will force image to be downloaded.
>>>>> Image at url(...) will be covered by linear gradient in full.
>>>>
>>>> background: linear-gradient(rgba(255,0,0,0.5), rgba(10,10,10,.25)),
>>>>  url(image.png);
>>>
>>> Why not
>>>
>>> background: url(image-with-that-gradient-on-top.png);
>>>
>>> ?
>>>
>>> This trick almost always requires knowledge about that
>>> image on your side so why not just to produce that image
>>> upfront?
>>
>> Because the image is a small repeating thing (a pattern for example)  and
>> I've no idea how much content will go in the box ?
>>
>> http://dev.l-c-n.com/CSS3_border-background/gradient3.html
>> (requires a recent Minefield build, didn't try to write the code for
>>  WebKit)
>
> This is a bit weak case I would say as:
>
> Alpha-math theorem:
> For any semi-transparent gradient on top of image there is always such a
> combination of  some gradient with semi-transparent image
> on top of it that produce the same visual result.
>
> Do I need to prove it or is it clear enough?

This is not true if the transparency is not constant and dimensions
are not known beforehand.

e.g. the effect of changing the font size in the provided example
cannot be simulated in that way.

> I strongly believe that benefit of having gradients and other synthetic
> background color distibutions to be addressible independently from images
> significantly overweights any multi-layer tricks that can be achieved.

Can you be specific about what you want to be addressable beyond what
is available through the different properties of multiple background
images?
Received on Monday, 9 November 2009 09:48:49 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 17:20:22 GMT