Fw: Re: text-intro-05-t

[Edited and forwarded with permission.]

----- Forwarded message from Piers Wombwell <piers@ekioh.com> -----

From: Piers Wombwell <piers@ekioh.com>
Date: Wed, 8 Dec 2010 13:43:11 +0000
To: cam@mcc.id.au
Subject: Re: text-intro-05-t

Hi Cam,

I think some of the SVG Tiny (and possibly Full) tests are incorrect, including this one.

The SVG Tiny spec and SVG 1.1 Full specs disagree on the handling, though SVG 1.1Full2 now agrees with SVG Tiny.

The key differences between the 1.1F1 spec is highlighted below.

SVG1.1F1:
For the ‘direction’ property to have any effect, the ‘unicode-bidi’ property's value must be embed or bidi-override.

SVG1.2T (and SVG1.1F2):
For the 'direction' property to have any effect on an element that does not by itself establish a new text chunk (such as the 'tspan' element in SVG 1.2 Tiny), the 'unicode-bidi' property's value must be embed or bidi-override.

unicode-bidi's default value is 'normal'.

The 'direction' property's default value is 'ltr', so the text laid out with the assumption that the primary reading direction will be left-to-right. However, the text happens to be Arabic, so appears reversed. The use-case for this is when the majority of your text is LtR, but it includes some inline RtL.

In summary, I believe text-intro-05-t would be valid under SVG1.1Full1, but invalid under SVG1.1Full2 and SVGTiny.

Another way of looking at it is all the examples in the SVGT spec, plus the W3C SVG Tiny RtL tutorial:
 http://www.w3.org/International/tutorials/svg-tiny-bidi/

They seemingly contradict the SVG T test suite's understanding of the text-anchor property.

Piers.



----- End forwarded message -----

-- 
Cameron McCormack ≝ http://mcc.id.au/

Received on Wednesday, 8 December 2010 21:02:28 UTC