Re: Transformed Pointer Coordinates?

On Tue, Feb 12, 2013 at 10:32 AM, Dirk Schulze <dschulze@adobe.com> wrote:

>
> On Feb 12, 2013, at 9:29 AM, Rik Cabanier <cabanier@gmail.com> wrote:
>
> > I agree. The vast majority of people are just interested in the 2d
> transform.
>
> At the moment yes. And for Pointer events you are probably not interested
> in a 3D point as well. I think we all agree in that. When it comes to the
> interface description, I don't see a reason to create two different
> interfaces. Better to make z=0 and w=1.
>

One reason is that it's significantly easier to specify and implement the
2d case.
As you know, the specification is unclear exactly how perspective and
transform-style are implemented. The 3D version of this API will need to
know all the transformations so it can be implemented correctly.


>
> >
> > Another issue with 3d is how transform-style [1] is treated.
> > for intstance:
> > <div id="a">
> > <div style="transform: rotate3d(...); transform-style: preserve-3d">
> > <div id="b" style="transform: rotate3d(...); transform-style: flat">
>
>
> >
> > Does it make sense to transform point between a and b?
>
> For NodeToNode transformation it probably does not make sense and an
> DOMException should be raised. For node to page, I think, WebKit still
> returns a 2D point at the moment.
>
> Greetings,
> Dirk
>
> > 1: http://www.w3.org/TR/css3-transforms/#transform-style-property
> >
> > On Tue, Feb 12, 2013 at 1:59 PM, Robert O'Callahan <robert@ocallahan.org>
> wrote:
> > Maybe I'm wrong but I feel like it would be best to keep 2D points and
> 3D points as separate interfaces. We don't want Web authors to wonder what
> "z" and "w" mean for the result of convertPointFromNode.
> >
> >
> > Rob
> > --
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> tvir uvf yvsr nf n enafbz sbe znal.” [Znggurj 20:25-28]
> >
>
>