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<P><FONT SIZE=2>Hello,<BR>
<BR>
Thanks for the reply! But does this involve first computing the value of the implicit function on a 3D grid and then running marching cubes?<BR>
<BR>
I should have mentioned that this is not an option as it will involve a computational cost which is cubic in the resolution (due to constructing the 3D grid), whereas a direct application of marching cubes should be more or less quadratic in the resolution (as the surface itself is two-dimensional, and only embedded in a 3D space).<BR>
<BR>
Christian<BR>
<BR>
<BR>
-----Original Message-----<BR>
From: Jérôme [<A HREF="mailto:jerome.velut@gmail.com">mailto:jerome.velut@gmail.com</A>]<BR>
Sent: Mon 7/6/2009 3:58 PM<BR>
To: Christian Walder<BR>
Cc: vtkusers@vtk.org<BR>
Subject: Re: [vtkusers] marching cubes on an implicit surface<BR>
<BR>
Hi,<BR>
You may want to build such a pipeline :<BR>
vtkImplicitFunctionToImageStencil -> vtkImageStencil -> vtkContourFilter<BR>
<BR>
It *should* do the trick... Yet I had never try it !<BR>
<BR>
Best,<BR>
<BR>
Jerome<BR>
<BR>
<BR>
2009/7/6 Christian Walder <chwa@imm.dtu.dk><BR>
<BR>
<BR>
Dear All,<BR>
<BR>
<BR>
I am completely new to vtk, and I am hoping it can solve my problem:<BR>
<BR>
<BR>
I have an implicit surface function mapping from R^3 to R (from three<BR>
dimensions to a scalar value), and I would like to run a marching cubes<BR>
type algorithm on it, to extract a mesh which approximates the zero<BR>
level set of the function. In principle it should be possible to use<BR>
some marching cubes library to do this by e.g. passing a pointer to the<BR>
function which evaluates the implicit surface function, along with<BR>
perhaps a bounding box and resolution, etc. However, from taking a quick<BR>
look it seems that vtk can only do this for voxel data, ie for functions<BR>
which are defined numerically on a 3D grid.<BR>
<BR>
<BR>
Does anyone know if it is in fact possible to do what I want? If so, can<BR>
anyone recommend a good reference or place to start?<BR>
<BR>
<BR>
best regards,<BR>
<BR>
<BR>
Christian<BR>
<BR>
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