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I read the tutorial of POVRAY but i did not understand how to draw isosurface over my xyz data points. In the tutorial they only talk about isosurface of function. Can anyone tell me is it possible to draw isosurface over data points such that isosurface covers all the data points. I tried the blob command. In the blob command i am connecting my two data points with cylinder. So whenever two cylinder overlap in any region there intensity become high and its look awkward. So, i thought to switch over isosurface.

ankit agrawal
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2 Answers2

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1) There are some XYZ data sets that could provide interesting results if you used blob SPHERES, and then played with the sphere radius or threshold to make the type of look you want.

2) In theory, any surface could be represented by a mesh2. However, the programming of such a surface will be much easier if it were unique in one of its axes (i.e., a "blanket" as opposed to a "football"). You would simply have to make the mesh out of triangles. I think the mesh2 example in the docs could get you there.

pterandon
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  • Thanks for the reply. I didn't understand how the normal_vectors are computed for smoothing the surface in this example. Is anyone have the idea about how the vertex normal was calculated in this example. http://www.povray.org/documentation/view/3.6.0/68/ – ankit agrawal Apr 26 '15 at 09:28
  • You could average the normal vectors of the adjacent triangles to create the normal vector of a vertex. But this works best when the shape is very smooth. I.e. when there is a sharp edge to the shape this does not work well AFAIK. You might want to use a `mesh` object instead, since you can use regular (flat) triangles in addition to or instead of smooth triangles. – posfan12 Mar 31 '17 at 02:36
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You can create isosurfaces from any pattern, also from the density file pattern, you could construct a density file (.df3) from your data points, although normally a density file would have gradients (think MRI scans).

For the generation of a mesh from a point cloud I would look for a dedicated triangulation tool.

ingo
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