[vtkusers] How to get the cg of a surface

[Hendrik Belitz]

Am Sonntag, 5. Juni 2005 09:02 schrieb An Jiye:
> Hi, everyone.
>
> I have used Marching Cubes alogrithm to extract an iso-surface.
> It is the surface of some object.
> Now I want to get the cg of this surface, how can I?
>
> Or I can calculate the center of gravity myself,
> but I need the coordinate of each pixel on the surface to do so.

No you don't the pixel coordinates. You only need the coordinates of all 
points (remember that you have a triangulated surface here) which can be 
extracted directly from the vtkPolyData structure. Doing this on a pixel 
basis indeed will give you the wrong results.

Regards
Hendrik Belitz