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Re: [SVGMobile12] SVGT12-207: Section 7.13 doesn't say how to get aspect ratio from viewBox

From: Andrew Shellshear <Andrew.Shellshear@cisra.canon.com.au>
Date: Tue, 21 Mar 2006 11:57:36 +1100
Message-ID: <441F4F80.2000602@cisra.canon.com.au>
To: www-svg <www-svg@w3.org>

Ian Hickson wrote:
 > On Tue, 21 Mar 2006, Andrew Shellshear wrote:
 > 
 >
 >> Ian Hickson wrote:
 >>  
 >>
 >>> In section 7.13 the SVG 1.2 Tiny spec says:
 >>>
 >>> # [...] the aspect ratio is calculated from the width and height of 
the #
 >>> viewBox specified for the current SVG document fragment.
 >>>
 >>> The specification does not say _how_ this is done. Should the height be
 >>> divided by the width, or vice versa, or something else?
 >>>    
 >>
 >> We have added:
 >>
 >> The aspect ratio is calculated by dividing width by height.
 >>
 >> to the list of rules for calculating the intrinsic aspect ratio.
 >>
 >> Please let us know shortly if this does not resolve your comment.
 >>  
 >
 >
 > That sentence alone doesn't seem to be enough; for example, does this 
mean the height and width attributes, the height and width parts of the 
viewBox attribute, or something else?
 > 
 >
The full paragraph is:

The intrinsic aspect ratio of the viewport of SVG content is necessary 
for example, when including SVG from an object element in XHTML styled 
with CSS. The intrinsic aspect ratio must be calculated based upon the 
following rules:

   * The aspect ratio is calculated by dividing width by height.
   * If the 'width' and 'height' of the rootmost svg element are both 
specified in absolute units (in, mm, cm, pt, pc, px, user units) then 
the aspect ratio is calculated from the 'width' and 'height' after 
resolving both values to user units.
   * If either/both of the 'width' and 'height' of the rootmost svg 
element are in percentage units, the aspect ratio is calculated from the 
width and height of the 'viewBox' specified for the current SVG document 
fragment. If the 'viewBox' is not correctly specified, or set to none, 
the intrinsic aspect ratio cannot be calculated and is considered 
unspecified.


Your comment was about whether aspect ratio is width divided by height, 
or the other way around.  I believe this addresses your comment.

Please let us know shortly if this does not resolve your comment.
Received on Tuesday, 21 March 2006 00:57:40 GMT

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