How to plot 3D field in povray

How to plot 3D field in povray

Post by Dr. Paul Fo » Tue, 07 Aug 2001 01:08:54



I would like to find an aesthetically pleasing way to plot a 3D collection
of points f(x,y,z) that are derived from a set of experimentally
determined points on a mesh in three-space.  My tentative goal at this
point is to use POVRAY.  My question is what is the best way to go about
doing such a thing? e.g. should I use isosurfaces?  Can I visualize the
data as a fog and swing the camera around to show different directions?
Any help here would be appreciated as from what I have read so far povray
is a fairly sophisticated tool and the water looks deep!  I am
particularly interested in examples (e.g. so I can hack them to fit my

 
 
 

How to plot 3D field in povray

Post by Chris Huf » Tue, 07 Aug 2001 02:54:06




> I would like to find an aesthetically pleasing way to plot a 3D collection
> of points f(x,y,z) that are derived from a set of experimentally
> determined points on a mesh in three-space.  My tentative goal at this
> point is to use POVRAY.  My question is what is the best way to go about
> doing such a thing? e.g. should I use isosurfaces?  Can I visualize the
> data as a fog and swing the camera around to show different directions?
> Any help here would be appreciated as from what I have read so far povray
> is a fairly sophisticated tool and the water looks deep!  I am
> particularly interested in examples (e.g. so I can hack them to fit my


You should probably get MegaPOV if you don't already have it, the Mac
version is here: http://users.skynet.be/smellenbergh/
It has a Carbon version that runs under Mac OS X...
This unofficial version adds isosurfaces, and has media improvements
that will speed rendering.

As for the visualization, it really depends on the type of data you have:
If it is height information over a 2D grid, a height_field object will
suffice...it takes an image as input and creates a surface where the
"height" of each point is determined by the brightness of the
corresponding point on the image.
If it is a mathematical function or a 3D voxel map, an isosurface is
perfect for it...you could also use the function as a density pattern
for media, so you don't get a surface but see the function as varying
densities in smoke or glowing gas. I'd recommend using emitting media,
at least at first...scattering media will be slower and harder to
control. Fog won't be useful for this.
If it is a collection of points...well, fitting a mesh to those points
would be difficult and probably not what you want. You might try a blob
object with a spherical component at the position of each point. You
could also use the blob pattern as a media density pattern...
If it is a mesh, you just need to convert it to something POV can read.
More specific information is needed...

--


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How to plot 3D field in povray

Post by (chensha » Wed, 08 Aug 2001 02:40:50




Quote:> I would like to find an aesthetically pleasing way to plot a 3D
> collection of points f(x,y,z) that are derived from a set of
> experimentally determined points on a mesh in three-space.  My
> tentative goal at this point is to use POVRAY.

I gather from your description that you're basically looking for a way to
render voxel-based data.  Unfortunately, Povray doesn't support for voxel
rendering in the conventional sense.  Short of using a different renderer,
you have three options: plot each point as an object, tessilate your voxel
data into a triangle mesh, or output your data as a .DF3 media density file
for use with media.

--
Coridon Henshaw -- http://www3.sympatico.ca/gcircle/csbh
"..To expect a good deal from life is puerile." -- D.H. Lawrence