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<DIV><FONT face=Arial size=2>Hi Randall,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Yeah - exactly. I'd have to look at it closer but
an alternative would be a vtkMetaball subclass that just defines one function,
then use vtkImplicitBoolean to sum up the functions- I'm not sure this would
work... the potential functions maybe coupled,if so- it wont.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Goodwin</FONT></DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=randall.hand@gmail.com href="mailto:randall.hand@gmail.com">Randall
Hand</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=goodwin.lawlor@ucd.ie
href="mailto:goodwin.lawlor@ucd.ie">Goodwin Lawlor</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=vtkusers@public.kitware.com
href="mailto:vtkusers@public.kitware.com">vtkusers@public.kitware.com</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, January 26, 2006 7:55
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [vtkusers] Re: Metaball
Simulation</DIV>
<DIV><BR></DIV>Clever.. so you mean I would derive a vtkMetaballs from
vtkImplicitFunction that basically had 1 user function "AddMetaball(float
position[3], float radius)". Then all i'll need is to override the
EvaluateFunction and EvaluateGradient to return the correct value, right?
<BR><BR>wow.. That's nowhere near as complicated as I was expecting to have to
do :) Thanks!<BR><BR>
<DIV><SPAN class=gmail_quote>On 1/26/06, <B class=gmail_sendername>Goodwin
Lawlor</B> <<A href="mailto:goodwin.lawlor@ucd.ie">
goodwin.lawlor@ucd.ie</A>> wrote:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Randall
Hand wrote:<BR>> I'm curious if there is any way in VTK to do a create a
MetaBall-type <BR>> dataset. Example of metaballs can be found
here:<BR>> <A
href="http://www.corelmag.com/1103/overview/Metaball_Modeling.html">http://www.corelmag.com/1103/overview/Metaball_Modeling.html</A><BR>>
<<A href="http://www.corelmag.com/1103/overview/Metaball_Modeling.html">
http://www.corelmag.com/1103/overview/Metaball_Modeling.html</A>><BR>><BR>>
Basically I want to be able to define points in 3d-space along with
a<BR>> Radius for each, and then have a vtkPolyData (or something like
it) <BR>> created from the results of the Metaball surface. Is
there any way to<BR>> do this in VTK? I can get a rough
approximation by using a vtkGlyph3d<BR>> and mapping a vtkSphereSource at
each point, but that leaves <BR>> intersecting geometry without the
smooth features that come from a<BR>> Metaballs type algorithm.<BR><BR>Hi
Randall,<BR><BR>This looks a job for a vtkImplicitFunction... maybe called
vtkMetaballs.<BR>vtkMetaballs would define a centre, a radius, and a
potential function <BR>for each metaball you add to the system. Then, just
sample it with<BR>vtkSampleFunction, and create the surface with a
vtkContourFilter.<BR><BR>Have a look at this paper: <A
href="http://tinyurl.com/7fdox">http://tinyurl.com/7fdox
</A><BR><BR>hth<BR><BR>Goodwin<BR><BR>_______________________________________________<BR>This
is the private VTK discussion list.<BR>Please keep messages on-topic. Check
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clear=all><BR>-- <BR>Randall Hand<BR>Visualization Scientist, <BR>ERDC-MSRC
Vicksburg, MS<BR>Homepage: <A
href="http://www.yeraze.com">http://www.yeraze.com</A>
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