Re: Place a DIV above all site content

In article <slrngdejap.5dq.spamspam@xxxxxxxxxxxxxxxxx>,
Ben C <spamspam@xxxxxxxxx> wrote:

On 2008-09-21, dorayme <doraymeRidThis@xxxxxxxxxxxxxxx> wrote:
In article <slrngddga5.agu.spamspam@xxxxxxxxxxxxxxxxx>,
Ben C <spamspam@xxxxxxxxx> wrote:

I hope dorayme is reading this. I kept claiming the canvas is
often transparent, but just saw this in Appendix E:

The canvas is transparent if contained within another, and given a
UA-defined color if it is not.

dorayme reads everything, it has come to earth to absorb material that
others find too painful. It takes that pain on so others do not have to
suffer so.

What it does with the material is try to make sense of it. So far it has
concluded that canvases are often transparent, sometimes not but when
not, one can also posit an Ultimate Opaque object.

I have given you some data (which you ignored perhaps because it looked
crazy) which suggests this ultimate object is not the viewport's back
but that of the browser itself, at least in FF3.

Yes, although it may be that every time FF3 opens a window it opens a
viewport. Only some of those viewports contain rendered HTML documents.


Ah... now, I think this is stretching it a bit. I know what you are
doing and it is a bit cunning and desperate at the same time. We must
have a few fixed anchors and not turn the whole area into quicksand.
Viewport is Viewport and for looking at webpages. We were not happy
about having just BODY and HTML, we needed Viewport to anchor our
understanding of things like absolute positioning and canvases and
transparency, You are turning about and degrading its lofty status by
comparing it to a mere desktop window. Have you no conscience?

The whole window in which Source appears is quite different in
appearance and function. That flash of colour I referred you to, and
made a movie of, suggests the simplest thing, the browser itself has
this Ultimate Coloured Rectangle and sports it by default whenever.

It is as if I caught a magician slip up in his trick. The browser has
this coloured rectangle in its right hand and is ever ready with it. It
had to withdraw it pretty smartly in the case of the source window and
let the source have its normal white bg. There was no evidence of the
white being overlain. It looked for all the world like the yellowy cream
(my answer to Bergamot's Sicko Green or B's Unconscionable Purple) was
hastily withdrawn. That Ultimate Opaque is there and belongs to the
browser and used in many of its tricks. It is not the poor Viewport's.

The toolbars, dialogue boxes, everything in Firefox is represented by
markup (not HTML but something called XUL) that it then renders using
itself.

But we could just as well say FF3 uses transparent viewports and puts
the UA-defined colour behind that.


OK, I am not really disagreeing with this. I just am a bit resistant to
the idea of viewports having backs. It is a window through which you
look. the rest of the show belongs to the website and the browser.

In many ways it's moot-- the idea is just to have a mental model that
works and is reasonably simple.

Basically, we can make merry with the colourless "UA-defined color".

But thanks, I will be looking, more closely at the sections you quote.

They also talk in Appendix E about painting the root element's
background on top of the canvas, so one interpretation of what they
meant is that the canvas _is_ one colour and is then _painted_ with
another colour.

That is what I always thought originally but you have pressed me into
seriously considering the essential transparency of canvases. I like
being pressed this way because it does explain quite a few things. But
there are limits.

To fix that all you need is a small change to 14.2-- rather than saying
"the background of the root element becomes the background of the
canvas" you would just say "the background of the root element is
painted on top of the canvas", like App. E does. The main point they're
trying to make in 14.2 is just that it covers the whole canvas.

There is no contradiction after all if one is OK with the idea that the
canvas is one colour and has another background colour (on top of that).

--
dorayme
.

Relevant Pages

  • Re: transparent color - background image.
    ... I know little about iframes, when I left frames I avoided even looking ... I found they wouldn't go transparent on Konqueror (which is similar ... there is something behind the canvas (by default the canvas is ... The viewport is just the same, except that it only has one child-- the ...
    (alt.html)
  • Re: Behavior of the xview call
    ... I need to calculate the "visible" width of a canvas, ... the width of the viewport. ... you should be able to do this using a combination of "xview" and the ... construction of the window, hence, the canvas hasn't yet been mapped ...
    (comp.lang.perl.tk)
  • Re: Any Idea for IE and Opera - Its working with Firefox ...
    ... You could say that the viewport is stealing the image there, ... I am thinking of the canvas as infinite, as 2-D, and as having ... scrolling behaviour of the root element background which is what gives ... that the root element background is applied to the viewport. ...
    (alt.html)
  • Re: Place a DIV above all site content
    ... often transparent, but just saw this in Appendix E: ... UA-defined color if it is not. ... background on top of the canvas, so one interpretation of what they ... "the background of the root element becomes the background of the ...
    (alt.html)
  • Re: Tradeoffs of setting background-color on html vs. body?
    ... that say it's not recommended to set background-color on the html ... The background on the root element is instead applied to the canvas ... from the main viewport). ... background may have got applied to the canvas in some circumstances. ...
    (comp.infosystems.www.authoring.html)