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Re: More on getObjectExtent()

From: Lofton Henderson <lofton@rockynet.com>
Date: Tue, 18 Nov 2008 16:51:39 -0700
Message-Id: <>
To: "Bezaire, Benoit" <bbezaire@ptc.com>, "WebCGM WG" <public-webcgm-wg@w3.org>
At 01:52 PM 11/18/2008 -0500, Bezaire, Benoit wrote:
>The wording says "[...] The bounding box calculation is based on the 
>abstract locus of the primitives within the APS."
>What does 'abstract locus' mean?

The locus is the set of points comprising the drawn primitive (it's a term 
I dredged up from my memory of some old math courses -- I hope I got it 
right).  "Abstract locus" means that things like line width are not 
included, but rather only the point positions as if the item were drawn 
with an abstract, infinitely fine pen.

>I'd like to know if getObjectExtent() returns a tight bounding box on a 
>given APS. i.e., given a polybezier, are control points part of the 
>bounding box calculations or not?

No.  The control points are part of the defining data, but not part of the 
drawn primitive.

Received on Tuesday, 18 November 2008 23:52:26 UTC

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