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Re: Background image display problems

From: Firespring <firespring@nfx.net>
Date: Sat, 28 Aug 1999 08:11:35 -0400
Message-ID: <37C7D1F7.5C88FAAC@nfx.net>
To: www-style <www-style@w3.org>
Hello,

Ian Hickson wrote:
> 
> On Tue, 10 Aug 1999, firespring wrote:
> 
> > [...] to bleed over the edges of their boxes a bit so as to soften the
> > sharp contrast of the different edges. And yes, I know this could be
> > done with multiple images layed out properly, or perhaps with border
> > or margin properties (if the major browsers ever implement them
> > correctly) but that seems cumbersome and inelegant to me. A property
> > something like:
> >
> >   background-bleed: Npx;
> >
> > might do it, where the Npx is the number of pixels that the
> > background image would be allowed to bleed over the edge of the
> > box. How the images actually look when they overlap would depend
> > upon how the opacity/transparency of each was defined of course.
> 
> While this seems like an interesting idea, I would suggest that there is
> already a more powerful way of doing this:
> 
> Use the 8bit alpha channel of PNG files.
> 
> i.e., convert your image to the PNG format, and make its edges
> progressively more transparent. PNG, unlike GIF, has 256 levels of
> transparency, rather than just 1.
> 
> Doing this means you can bleed circles and triangles and gigerbread men
> into the page, rather than just squares.
> 
> Similar things will probably be possible with SVG, so if you cannot
> convert your image to PNG, then you would be able to write an SVG wrapper
> for it that did what you want.
> 
>

While your suggestion is worthy and appreciated Ian, and I will 
most definitely experiment with it, it doesn't solve the problem 
for GIFS, JPGS, etc., and it doesn't solve the problem of how the 
space between adjacent boxes looks. 

What I mean is, if I display two adjacent boxes, each with a 
different graphic, and some type of border or margin, then the 
border/margin presently takes its color/image from the background. 
What I would like to see is some way where two adjacent graphics 
could bleed OVER their shared border/margin so as to appear as
if that one flowed into the other and so they obscure the
margin/border image/color.

Now of course this could probably be done by setting the border/
margin widths of each box to zero, and carefully tailoring the
edges of each graphic to match the other, but I think it would
be much more useful if CSS could control the overlap transparency
of the boxed graphic with the background/border/margin/etc..


Rick J.
firespring@nfx.net
Received on Saturday, 28 August 1999 08:02:55 GMT

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