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Re: Fwd: Again with the getIntersectionList()

From: Boris Zbarsky <bzbarsky@MIT.EDU>
Date: Sat, 14 Nov 2009 00:54:49 -0500
Message-ID: <4AFE4629.2030502@mit.edu>
To: Rick <graham.rick@gmail.com>
CC: www-svg <www-svg@w3.org>
On 11/14/09 12:33 AM, Rick wrote:
> The scenario you describe below is useful for finite integer math, in
> rendering engines for example, where you are dealing with pixel sets.
> In floating point Cartesian math, they all all intersect.  Euclid said
> so.

Yes, I'm well aware of the different definitions of intersection 
involved.  Or more precisely the different definitions of "rectangle".

How about addressing the substance of my comments (which is that the 
spec needs to explicitly call out how intersections work here, since on 
the web they often work in a somewhat different way)?  That's assuming 
that is in fact the way we want them to work, of course.  I take your 
comments to be a roundabout way of saying that we do want them to work 
that way.

-Boris

P.S.  Strictly speaking, Euclid never defined what he meant by 
"intersect" (he assumed it was obvious), nor did he define whether his 
quadrilaterals are open or closed (or equivalent, since he didn't have 
those concepts).  He doesn't much talk about intersections of 
quadrilaterals with each other.
Received on Saturday, 14 November 2009 05:55:26 GMT

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