[vtkusers] Volume Rendering from Cloud Points

[Charl Botha]

On Fri, Aug 1, 2008 at 11:22 AM, Mohammed Amine SAHTARI
<msahtari at gmail.com> wrote:
> I am trying to do a volume rendering of a large data set. I has a group of
> points, each point defined by : a position [ X, Y, Z ] and a Scalar.
> The implemented volume rendering techniques (RayCast,..) require a
> structured grid or an unstructured grid as input.
>
>
> Please let me know the correct / best way to do this.

"Correct" and "best" depend mostly on what your end goal is.

For example, there are point-based volume rendering techniques around
(see great work by the group of Markus Gross) that focus on directly
rendering this type of data.  If your point-cloud is range-scanning
type of data, these techniques are a good bet.

In stock VTK, I don't know of any point-based direct volume rendering
techniques.  However, you can pass your points through a
vtkShepardMethod filter to turn them into a surface that you can
visualise.  You could also try the vtkDelaunay3D filter.  There are
other point-cloud -> surface methods, such as Powercrust (VTK version:
http://www.sq3.org.uk/powercrust/ - also see the original site:
http://www.cs.utexas.edu/users/amenta/powercrust/welcome.html).

Good luck,
Charl Botha

-- 
http://visualisation.tudelft.nl/CharlBotha