if you are working on a mesh. and the normal vector of a triangle facet can be obtained<div>by doing a cross product of two edges, right? and if you want the normal vector</div><div>of the vertices of a triangle you can obtain it by interpolating of surrounding facets or</div>
<div>if you are extract the isosurface from volume data, the normals can be calculated by</div><div>central difference or any finite different methods based on the volume data.(see Marching cubes algorithm)</div><div><br>
</div><div>there are plenty of research papers addressing this issue. i am not exactly sure</div><div>how VTK could achieve this by calling any function..</div><div><br></div><div>good luck</div><div><br></div><div>O.S.</div>
<div><br><br><div class="gmail_quote">On Tue, Oct 25, 2011 at 12:35 AM, andon <span dir="ltr"><<a href="mailto:antoniod987@gmail.com">antoniod987@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
OK, I've understood this....but i need to get out an angle, in particular i<br>
need to get the orientation of the cell on wich i've extracted the<br>
normal..do you know ho can i do this???<br>
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