W3C home > Mailing lists > Public > www-svg@w3.org > October 2008

animate-elem-35

From: Piers Wombwell <piers@ekioh.com>
Date: Thu, 9 Oct 2008 14:21:19 +0100
Message-Id: <7EBE26EC-BF13-4DC2-985E-8C572711FF8F@ekioh.com>
To: www-svg@w3.org

Hi guys,

Just had a quick glance at your test suite results, and noticed a  
comment against test animate-elem-35.

The problem here is down to fixed point maths. The inside of the 'A'  
is made from a path using relative co-ordinates which don't map well  
to fixed point maths. So when it draws the horizontal line to complete  
the path in the bottom-right, the end point doesn't quite match the  
start point. The closepath then expects the current point to be equal  
to the start point, but they aren't quite, and so it draws a sub-one- 
pixel line -- and so the line joins aren't as expected. Rather than  
one line join between the last and first lines (_ and \), there will  
be two line joins, one between the _ and the short closepath, and one  
between the short closepath and the first line \.

I assume the problem is the same on the outer part of the 'A', but  
haven't confirmed this.

I'm not sure what precision you need for the test to pass, but  
floating point tends to pass and fixed point (24.8) fails in my  
experience.

Piers.
Received on Thursday, 9 October 2008 14:14:54 GMT

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