Re: Rotation about centroid and scaling to shrink in place (without scripting)

Hi, David-

ddailey wrote (on 11/14/10 6:05 AM):
> Teaching people to use SVG is a bit different than writing a spec I
> suppose, and perhaps, even a bit different than building a browser.
> Sometimes, I can't help but think we should take lessons from those who
> try to learn to use our things. It may give insights into designing
> things.

I agree.  I do a lot of speaking on SVG, and helping people learn SVG, 
and it has been a real boon to understanding how we should simplify the 
language for the average and expected user.

I've been involved in some education initiatives at W3C too, and I'm 
hoping to get more direct feedback into the technology design process 
from from teachers, who have valuable insight and experience into how 
easy or hard it is for the average student to learn particular aspects 
of W3C technologies.


> I think it would be nice to have attribute values for rotations like
> transform="rotate(45, 'center' )" and transform="rotate(45,
> 'center-of-Mass' )" where center is the center of the getBBox() of the
> object being transformed and center-of-Mass is its 2nd central moment
> and for scaling like transform="scale(.5, 'center' )" so that the thing
> shrinks relative to its center rather than to 0,0.
>
> One can use script to do it, but suppose we want to enable people to do
> it without script.

Indeed, we are working with the CSS WG to have more friendly transform 
syntax for use in both SVG and HTML, similar to what you have proposed, 
and we intend to have a stable draft by June 2011; along the way, we 
will have updated working drafts which we welcome your feedback on.

I don't think that we are currently talking about adding a centroid 
keyword, though I understand your request for it.  The centerpoint case 
is definitely making it in, however.

Regards-
-Doug Schepers
W3C Team Contact, SVG, WebApps, and Web Events WGs

Received on Sunday, 14 November 2010 23:31:08 UTC