Re: [css3-2d-transforms] rotation and animation

I've already asked that the CSS WG remove this restriction on <angle>:

[CSS3Units] angles should not be normalised
http://lists.w3.org/Archives/Public/www-style/2008Nov/0545.html

Dean


On 24/03/2009, at 1:32 AM, Dr. Olaf Hoffmann wrote:

> Hello,
>
> this comment applies to css3-3d-transforms as well.
> http://www.w3.org/TR/2009/WD-css3-2d-transforms-20090320/#animation
> http://www.w3.org/TR/2009/WD-css3-3d-transforms-20090320/#animation
>
>
> In the related section about the transformation functions it is  
> noted, that
> for the <angle> type CSS Values and Units apply:
> http://www.w3.org/TR/css3-values/#angles
> This notes:
> "Angle values should be normalized to the range 0-360deg
> by the user agent."
>
> For static displays this might be useful, but for animation,
> 1) it does not note, whether the borders of the range are
> included or not or one included and the other excluded,
> what can result in a big difference for an animation from
> 0deg to 360deg.
> 2) authors might want to have a rotation from 30deg to 750deg,
> what means two complete turns and not no animation,
> or maybe from 90deg to -90deg, what is different from an
> animation from  90deg to 270deg (what has a
> different rotation direction too).
> Concerning animation I think, it is pretty useful not to
> modify the given values because this results in quite
> different effects as typically intended by the author,
> respectively authors cannot get the intended animation
> effect with only one rotation function at all.
>
> Best wishes
>
> Olaf
>
>