[vtkusers] How to visualize angular velocity of spherical particles?

[Sean McInerney]

How about texture mapping a bitmap of some arrows onto the sphere and 
then using vtkGlyph3D to position and orient each sphere? The bitmap 
could be something like this:

+--------------------+
|                    |
|                    |
|                    |
|      |\        |\  |
| +----+ \  +----+ \ |
| |       \ |       \|
| |       / |       /|
| +----+ /  +----+ / |
|      |/        |/  |
|                    |
|                    |
|                    |
+--------------------+

-Sean

Rasmus Hemph wrote:
> I am simulating approximately 100 particles wich are moving and
> colliding in a 3D box-like domain. I am able to attach a spherical glyph
> to each particle point in my field using vtk and tcl, which gives a nice
> visualization. 
> 
> My problem is that I want to somehow show the angular velocity of the
> spheres. The simulations gives me an angular velocity vector omega,
> which I map to the particle points, and that gives me an idea of the
> rotation. However this is not very intuitive, and it would be much nicer
> if I could color half of the sphere in some other color and rotate that
> half in the direction of the angular velocity vector in each timestep. 
> 
> I have so far created that "half sphere" but have not yet come up with a
> good way of rotating that at each timestep in the omega direction
> (different omega for all spheres). I would think that somebody has come
> across this problem before, and I am hoping for suggestions of some
> kind.
> 
> On the bottom of http://www.tfd.chalmers.se/~md8hemra/modeling.html 
> I have a 2D-movie-version (created in matlab) of what I want to achieve
> in 3D.
> 
> Thanks in advance.
> 
>