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Re: Transformed Pointer Coordinates?

From: Robert O'Callahan <robert@ocallahan.org>
Date: Tue, 12 Feb 2013 17:31:22 +1300
Message-ID: <CAOp6jLZ6J2vbohbfDaDFycBPHt37vxu=w8fKCcwZWSLXpbfx0g@mail.gmail.com>
To: Dirk Schulze <dschulze@adobe.com>
Cc: Jacob Rossi <Jacob.Rossi@microsoft.com>, "Tab Atkins Jr." <jackalmage@gmail.com>, Simon Fraser <smfr@me.com>, Doug Schepers <schepers@w3.org>, "public-pointer-events@w3.org" <public-pointer-events@w3.org>, "public-fx@w3.org" <public-fx@w3.org>, www-style list <www-style@w3.org>
On Tue, Feb 12, 2013 at 5:07 PM, Dirk Schulze <dschulze@adobe.com> wrote:

> I trust web authors to understand what z is for. w might be a bit more
> difficult but might not even be necessary to specify. If we add a new
> element into the web platform we should think beyond the current needs. I
> believe that this interface would be useful for other situations like 3D
> transforms or WebGL contexts. Especially CSS Transforms have a lot of
> situations where you get from a 2D context into a 3D context. You may would
> need to return different object types depending on the current
> transformation, this seems to be difficult in the long term.
>

I guess z is innocuous since ignoring it is OK, but I really don't want to
force Web developers to divide by w.

I suppose we can have convertPointFromNode return the full Point and
specify that it always returns a w value of 1.0.

If Point is a dictionary, which memberes x/y/z/w should be present in the
result of convertPointFromNode? I think x/y/z should be and w shouldn't be.
I think it would be really ugly to have convertPointFromNode return
something that looks like a JS object which always has a vestigial "w:1.0"
member.

Is it actually safe to create a DOM interface called Point? It doesn't
sound very safe to me...

Rob
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Received on Tuesday, 12 February 2013 04:31:56 GMT

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