RE: [css-compositing]new Editor's draft posted

Hi Rik,

 

I don't know if any of these experiments would be useful or not, but last
summer I did quite a bit of work with various blending and compositing
schemes across browsers. It was utterly astonishing (dare I say dreadful
after all these years?) how little agreement browsers had about how to
combine colors using filters. Consistent with a decade's experiments, Opera
and ASV generally behave as an author might hope, regardless of the spec's
inscrutability. 

 

See for example 

http://cs.sru.edu/~ddailey/canterbury/Browsers.html

 

Look, for example, at  http://cs.sru.edu/~ddailey/svg/V9.svg to see an
example of how poorly browsers agree on basic Venn diagrams to illustrate
subtractive and additive color model, as shown in your compositing draft.
Chrome behaves rather humorously here, and Firefox just refuses to try. 

 

A few hundred experiments can be accessed from the umbrella at
http://cs.sru.edu/~ddailey/canterbury/index.htm . This was for a paper
prepared not as an SVG advocate, but as a mathematician trying to accomplish
practical things in the area of data visualization. SVG was found to be
rather wanting in utility  The academic context can be seen at
http://ceur-ws.org/Vol-854/paper6.pdf . Folks with an interest in the basic
psychophysics of data visualization may take an interest. 

 

You can also see, in many of these examples, just how much work (oftentimes
hideously complicated) an author most do in order to bring about a desired
effect. I am optimistic that the new SVG will be able to fix some of these
things and convince, once and for all, the implementers to read the text in
the same way (that will hopefully have some resemblance to what people might
want, actually, to do).

 

Cheers

David

 

 

 

From: Rik Cabanier [mailto:cabanier@gmail.com] 
Sent: Monday, May 20, 2013 11:42 PM
To: www-svg
Subject: Fwd: [css-compositing]new Editor's draft posted

 

 

---------- Forwarded message ----------
From: Rik Cabanier <cabanier@gmail.com>
Date: Mon, May 20, 2013 at 8:42 PM
Subject: Re: [css-compositing]new Editor's draft posted
To: public-fx@w3.org, www-style list <www-style@w3.org>


In preparation of the Tokyo face-to-face, I made the compositing spec [1]
ready for the next working draft.

I added several examples and did general cleanup. 

 

During the joint FX day, I would like to discuss the issue of how we can
determine what the backdrop of an element with blending is. 

Specifically:

- what CSS constructs create groups that limit the backdrop

- how can we specify this and in what spec should we do this

- how can we ensure that this can be implement in a interoperable way.

 

 

 

1: https://dvcs.w3.org/hg/FXTF/rawfile/default/compositing/index.html

 

On Fri, Apr 19, 2013 at 1:07 PM, Rik Cabanier <cabanier@gmail.com> wrote:

All,

 

a new version of the compositing and blending spec was posted here:

https://dvcs.w3.org/hg/FXTF/rawfile/default/compositing/index.html

 

I removed the following features that were not going to make it in level 1:

- compositing on CSS element

- compositing on backgrounds in CSS

- shorthand that combines blending and compositing

- knock-out

They will be moved to the next version of the specification.

 

The biggest open issue in the spec is defining how 'grouping' is defined so
we can get inter-operable behavior across browser engines. [1]

We're currently working on a test matrix that explores browser differences
in this area.

 

Please review if you have time and let me know if you have any concerns.

I would like to publish this as a new Working Draft.

 

1:
https://dvcs.w3.org/hg/FXTF/rawfile/default/compositing/index.html#csscompos
itingrules_CSS