These demos use Geomview 
[see the chapter Geomview in the cgal manual - support library:
Geomview 1.8.1 is required.  The geomview command must be in the user's $PATH,
otherwise the program will not be able to execute.]
 
------- gv_interpolation_2 -------------------------------------------------
using Geomview

This demo program dumps the plot of the different interpolation functions
using a very simple data set
shows:	the differentiability (or not) at the data points
	the closeness to the gradient at the data points	

1) Construction of a Delaunay triangulation of the data points.
 
2) Interpolation on a grid using a user chosen interpolation function.

3) Dumps the plot of the interpolation functions (.off file)

4) Displays the data points in geomview.
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------- surface_voronoi -----------------------------------------------
This demo program displays the intersection between the three dimensional 
Voronoi diagram of a point cloud issued from a surface (sphere,cylinder 
or cube) and the tangent plane of another surface point. 
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