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RE: BasicTiming011

From: Sean Hayes <Sean.Hayes@microsoft.com>
Date: Sat, 25 Apr 2009 19:33:37 +0100
To: Philippe Le Hegaret <plh@w3.org>
CC: Public TTWG List <public-tt@w3.org>
Message-ID: <AB3FC8E280628440B366A29DABB6B6E8070E880F61@EA-EXMSG-C334.europe.corp.microsoft.com>
In timed text we define that for lineHeight:

"If the value of this attribute is normal, then the initial value of the style property must be considered to be the same as the largest font size that applies to any descendant element."

So whatever the default fontSize is, the lineHeight should be too, thus 3em should work of the height of the box. If this is an incorrect assumption and someone can point me to the reference as to why, then I'll change it. But I believe given the current definition the test is correct as it stands.

Thanks,
Sean.

-----Original Message-----
From: Philippe Le Hegaret [mailto:plh@w3.org]
Sent: 24 April 2009 4:21 PM
To: Sean Hayes
Cc: public-tt@w3.org
Subject: RE: BasicTiming011

On Wed, 2009-04-15 at 22:18 +0100, Sean Hayes wrote:
> Thanks Phillipe.
>
> Yes you are correct, there are more than three lines of content, but cctually the three lines in BasicTiming011 is intended to refer to the fact that the extent of the region is (3em), and as the overflow defaults to hidden; if you can see more than three lines at one time, then the implementation is incorrect.

I fixed the default of overflow in my implementation and I now see 2.5
lines. I looked at why this was the case:

The default value of line-height is normal is defined as a "reasonable"
value based on the value of the font-size, which is recommended to be
something between 1.0 and 1.2 (in order words, 1em to 1.2em). The height
of 3em also refers to the size of the font-size. So, if you want to
guarantee that the third line is completely visible, you should also set
a value for line-height in the test and take it into account for the
height of the region.

Philippe
Received on Saturday, 25 April 2009 18:34:27 GMT

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