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

Re: Tilting my school map.

From: Dr. Olaf Hoffmann <Dr.O.Hoffmann@gmx.de>
Date: Mon, 28 Jan 2008 15:15:24 +0100
To: www-svg@w3.org
Message-Id: <200801281515.24887.Dr.O.Hoffmann@gmx.de>

If I understand this correctly, there are data/objects from an
n-dimensional space (obviously n=3 of a map, a surface
z=z(x,y) ) to be transformed or projected to the two-dimensional 
SVG canvas. The main problem is, that there is no possibility to put 
three-dimensional objects into a SVG document at all, therefore
because there is no object, there is not need for transformations
and projections in SVG.

I have examples for this problem for paths noted in a three dimensional
space, using transformations and different projection methods and 
some approximations for non-affine projections, but all these operations 
are done using a more or less simple PHP script having simples paths
as result. In this simple examples the orientation of the object is
animated. Typically such files get very large for complex objects.
Therefore it is not impossible using such a  PHP script, but currently
not very comfortable. 

However for simple objects and simple projection methods/approximations, 
it may work to feint the effect with the available matrix transformation 
available in SVG.

If z(x,y) is available, it may work too, as already mentioned in the other
discussion to apply a displacement filter to feint the effect, using a
color/opacity representation of z(x,y) to distort a two dimensional image
to simulate a simple projection model approximation.
Received on Monday, 28 January 2008 14:19:50 GMT

This archive was generated by hypermail 2.3.1 : Friday, 8 March 2013 15:54:38 GMT