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RE: [css3-images] remaining gradient issues

From: Brian Manthos <brianman@microsoft.com>
Date: Tue, 26 Jul 2011 23:06:22 +0000
To: Brad Kemper <brad.kemper@gmail.com>
CC: www-style list <www-style@w3.org>
Message-ID: <9710FCC2E88860489239BE0308AC5D170FDC20@TK5EX14MBXC264.redmond.corp.microsoft.com>
Brad:
> Well I, for one, found term "gradient vector" an unfamiliar and mathy way
> of talking about direction. Anyone can understand what a line is though,
> and that it can be described by endpoints and direction.

Incorrect.

(1) A line does not have a direction.  You might argue it has two directions, but it definitely does not have exactly 1 direction. 
(2) A line does not have endpoints; instead it extends infinitely.  A line can be indicated by expressing two points that it passes through.  A line *segment* has endpoints.
(3) "mathy" --  More specifically it's geometry.  Without geometry, it's a bit difficult to talk about gradients at all.  Much of CSS uses both "general math" and specifically geometry.  Are you suggesting we stop using one or both of them going forward for CSS?  I disagree strongly.


Here are some Wikipedia phrasings that align with my understanding from early on in school:

http://en.wikipedia.org/wiki/Line_(geometry)
Line:
"a line in the Euclidean plane as the set of the points whose coordinates satisfy a given linear equation."
Line segment:
"A line segment is part of a line that is bounded by two distinct end points and contains every point on the line between its end points."

http://en.wikipedia.org/wiki/Euclidean_vector
Vector:
"... a Euclidean vector is a geometric object that has both a magnitude (or length) and direction"


Terms such as "unit vector" refer to specialized vectors that have a magnitude/length of 1.
Received on Tuesday, 26 July 2011 23:06:50 GMT

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