W3C home > Mailing lists > Public > www-svg@w3.org > October 2010

advanced gradients

From: Andrew Matseevsky <a_matseevsky@yahoo.com>
Date: Sun, 3 Oct 2010 13:55:21 -0700 (PDT)
Message-ID: <645942.67265.qm@web45408.mail.sp1.yahoo.com>
To: www-svg@w3.org
Hi, boys. Take some additional info concerning advanced gradients. Look at two attached images. They are in fact pieces of a real altitude map, which reconstruction is based on a set of control points (small red crosses). These images can be drawn, using traditional technique- set of regions, contours, bounding theses regions and so on. Believe me, it is not so simple- to interpolate set of altitudes from set of control points to the whole region to be painted, calculate position of isohypses, convert them to vector objects and so on. What I'm trying to explain is that two last operations are odd. The first one is a must of course, but pure user might relay on a browser, if this one would be able to offer him such functionality. An image, created as a result of interpolation from the set of control points is a vector object too and there is no need to convert it to something else. Scaling is absolutely simple- compare SVG0 and SVG2. I do think, that such
 functionality will be very useful for large number of scientific applications (cartography, meteorology and so on). Set of input parameters has to include border of a region, of course, set of control points, some parameters, describing isohypses (step between two nearest ones, their color and width) and color profile (the simplest is a straight line segment, of course- first value plus corresponding color and last value plus corresponding color too). You may try my program, what draws a curve through the set of points (Release folder). This is a draft, of course, and currently has some small defects for my point of view. But, its behavior can be changed without much effort. At least, it does not create stupid loops like katmulli-I-do-not-remember-who-else splines does.
Regards, Andrey.




Received on Sunday, 3 October 2010 21:02:01 GMT

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