Warp <war### [at] tagpovrayorg> wrote:

> > Christoph Hormann's Earth renditions, apparently done with mesh2s
> > converted to isosurfaces (http://earth.imagico.de/technical.html) made
> > me drool instantly... and as he had done an include called "IsoCSG", I
> > wonder whether a mesh2 to isosurface conversion feature was contained
> > therein. But when I looked over the documentation of version 0.7, I
> > found no hint about how to do this. Could it be that only a version not
> > yet released contains this - or do I have to do it an entirely different
> > way! But there MUST be some way to convert mesh2s into isosurfaces...
>
>   Sorry for asking, but for what possible reason would one want to
> convert a mesh into an isosurface? A conversion to the other direction
> would make sense and, in fact, be really useful (at least in terms of
> rendering speed). However, converting a mesh to an isosurface seems to
> be completely backwards. Why would one want to do that?
>
>   (One could perhaps argue that you can apply any kinds of transformations
> to an isosurface. However, you can do that to a mesh too, although it
> requires more indirect means. If you put your vertices and normal vectors
> in arrays and then create the vertex and normal vectors of the mesh from
> those arrays, you can apply any transformations you want to those vertices
> in the arrays before creating the mesh, thus achieving free transformations.
> While not absolutely trivial, it's not that hard either.)
>
> --
>                                                           - Warp

A very interesting use case (to me) would be e.g. to model a comet where a rough
3D model is available in the form of vertices (e.g. 67P from Rosetta data), and
you would want to add some fake detail in order to make close-up renderings look
less artificial.

If the mesh was an isosurface in the first place, modifying it to add additional
fake detail would be straightforward!

Post a reply to this message