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Re: question on spec

From: Jon Ferraiolo <jferraio@Adobe.COM>
Date: Wed, 27 Jun 2001 11:00:38 -0700
Message-Id: <4.3.2.7.2.20010627105835.00e3b2c0@mailsj>
To: David Turner <david.turner@freetype.org>
Cc: Jon Ferraiolo <jferraio@Adobe.COM>, Wendell Piez <wapiez@mulberrytech.com>, www-svg@w3.org
At 07:43 PM 6/27/01 +0200, David Turner wrote:
>Hello,
>
> >
> > 1) On the outermost 'svg' element, you can define the instrinsic
> > width/height of the graphic in "px" units. In this use case, a "px" is
> > generally an system-dependent unit of measure. On many systems, a "px" will
> > map to one device pixel, and different devices have different resolutions,
> > so "px" might cause different sizes rendering on different systems. Also,
> > on very high-res monitors or on printers, a "px" might be an abstract
> > measurement typically in the range of 1/72 to 1/120 inch, again possibly
> > causes different rendering sizes on different systems.
> >
> > This case is the reason for the words: "...use of px units ... can cause
> > inconsistent visual results on different viewing environments since the
> > size of '1px' may map to a different number of user units on different
> > systems..." But now that you bring this up, I think some additional
> > rewording may be warranted.
> >
> > 2) Otherwise, "A px unit and a user unit are defined to be equivalent 
> in SVG."
> >
>The following makes me wonder. Isn't it simpler to say that:
>
>   A - a "px" is always equal to a user unit
>
>   B - the initial/outermost viewport transform should typically
>       map 1 user unit to 1 screen pixels (with variation for
>       printers, etc..)
>
>It seems to me that what's currently happening..
>
>Comments ?

Yes, that is pretty much what's happening most of the time today.It might 
be appropriate for more careful phrasing within the specification itself.

Jon Ferraiolo


>- David Turner
Received on Wednesday, 27 June 2001 14:16:10 GMT

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