[vtkusers] Removing cells inside solids !

[Malcolm Drummond]

Hi Sebastien

What I would do is make a copy of the pointset and then translate it (with
transform filter) by your extrusion vector. Number of original points = n :
Set total number of points for your output = 2n, copy the old points into
the new output (0 ... n-1), then copy in the new translated points (n ...
2n-1). Now you can 'stitch' up the quads using your old polygon indexes and
the n offset (so a segment [i, j] would become a quad  [i, j, j+n ,i+n])
(also make sure you connect the last quad back onto the first). Now do the
tesselation of the polygon, then access the tesselator outputs cell-array -
use the indexes directly for the first cap, offset by n for the second cap.
I think it will work.

Malcolm

----- Original Message -----
From: "Sebastien Auclair" <sxa at fluent.com>
To: "Malcolm Drummond" <malcolm at geovision.co.za>; "vtkusers"
<vtkusers at public.kitware.com>
Sent: Tuesday, June 03, 2003 3:22 PM
Subject: Re: [vtkusers] Removing cells inside solids !


> I think i can pretty much handle the quad creation stuff and the capings
> generation... (Each through manual cell creation.)
> But how can i use the 2 generated caps and quad string to form a single
> dataset,... How to merge everything.
>
> Thanks !
>
> ____________________________________
> Seb
>
> ----- Original Message -----
> From: "Malcolm Drummond" <malcolm at geovision.co.za>
> To: "vtkusers" <vtkusers at public.kitware.com>
> Sent: Tuesday, June 03, 2003 4:50 AM
> Subject: Re: [vtkusers] Removing cells inside solids !
>
>
> > Hi Sebastien
> >
> > How about creating your own extrusion before tesselation. It would only
> > involve the creation of quads (one per line segment) describing the
'wall'
> > around your polygons. You could then cap the top and bottom with
> tesselated
> > polygons
> >
> > HTH
> > Malcolm
> >
> > ----- Original Message -----
> > From: "Sebastien Auclair" <sxa at fluent.com>
> > To: <vtkusers at public.kitware.com>
> > Sent: Monday, June 02, 2003 10:26 PM
> > Subject: [vtkusers] Removing cells inside solids !
> >
> >
> > > Sorry for this repost but we never had any answers and it is now
> becoming
> > a
> > > critical issue for us.
> > >
> > > Is there a filter that would remove the facets inside a solid ?
> > >
> > > Let say i have a square formed with two triangles. (See attached
image )
> > > I extrude this square to get a cube.
> > > Because ALL edges are extruded to produce facets, the resulting cube
> will
> > > have an unacessary internal diagonal facet.
> > >
> > > Is there a vtkFilter that could remove those internal topologies ?
> > >
> > > Thanks !
> > > _____________________________________
> > > Seb
> > >
> > >
> >
> > _______________________________________________
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