[vtkusers] Creating a lens effect when moving over the surface

David.Pont at ForestResearch.co.nz David.Pont at ForestResearch.co.nz
Thu Feb 26 15:06:59 EST 2004


Vidya,
   a few thoughts:

Create a second renderer and camera, link the second camera to move with
the first and show a magnified image, say at the centre of the view.

Use vtkInteractorStyleUser (or your own derived vtkInteractorStyle) to
detect mouse events, invoke the base class method to move the main camera
(or actor), get the main camera parameters and use to move your second
camera.
Get a magnify effect but either placing the second camer closer (each time)
or change its focal settings? (once).

To display the magnified image:
- define a smaller viewport within the current window that the second
renderer uses, not at all sure if this is possible?;
- use offscreen rendering with the second renderer, get the image output
and texture onto a vtlPlaneSource. Use alpha 0 in the image to clip the
output image to a circular (or any) lens shape, you could also write pixels
to create a frame around the lens...

vtkPlaneWidget might be useful to move the lens independant of the scene,
but you might also get this by using interactor style actor or camera ...

  Dave Pont



                                                                                                               
                      "Vidya Setlur"                                                                           
                      <vidya at cs.northwe        To:       <vtkusers at vtk.org>                                    
                      stern.edu>               cc:                                                             
                      Sent by:                 Subject:  [vtkusers] Creating a lens effect when moving over    
                      vtkusers-admin at vt         the surface                                                    
                      k.org                                                                                    
                                                                                                               
                                                                                                               
                      26/02/2004 05:14                                                                         
                                                                                                               
                                                                                                               






Hi,

I would really like to know if someone has any information/pointers to
creating a "magnifying lens effect" while moving across a planar
surface.

Thanks,

Vidya


-----Original Message-----
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Sent: Wednesday, February 25, 2004 10:05 AM
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Today's Topics:

   1. Re: Installing VTK 4.2 on PC (Laurent Mundeleer)
   2. Re: associating datra to polydata (Malcolm Drummond)
   3. RE: memory leak in windows/mfc app (de Boer Ingo)
   4. Re: memory leak in windows/mfc app (Mathieu Malaterre)
   5. please someone help me on this code (david  michell)
   6. Texture-mapping based volume rendering (Weiguang Guan)
   7. Smoothing (Ted Vu)
   8. Using multiple Vectors (Uwe Rempler)
   9. surface mesh / terrain decimation
(=?iso-8859-1?Q?S=E9bastien_MARAUX?=)

--__--__--

Message: 1
Date: Wed, 25 Feb 2004 15:21:30 +0100
From: Laurent Mundeleer <lmundele at ulb.ac.be>
To: vtkusers at vtk.org
Subject: [vtkusers] Re: Installing VTK 4.2 on PC

Hi Andres,

I'm not sure, but when I read you, you seems to forget the 3)
After configuring your build with cmake, you need to compile and build
the vtk package.
To do that, click on the VTK.dsw to open the Visual Studio project, and
build the BUILD_ALL project.
Once it is done, you can try to compile a vtk example, first using cmake

to configure it, as for the vtk package, and then building it in Visual
Studio.

Laurent

>Message: 1
>From: "Andres Kurkit" <sergio_monagas at hotmail.com>
>To: vtkusers at vtk.org
>Date: Wed, 25 Feb 2004 11:41:57 +0000
>Subject: [vtkusers] Installing VTK 4.2 on PC
>
>Hello,
>I am trying to install VTK 4.2 on my PC (Windows XP). I am following
>the instructions included in the Readme file that came with VTK:
>
>PC Installation
>
>  1) Install the VTK 4.2 distribution by unzipping into the
>     appropriate directory.
>
>  2) Execute CMakeSetup. This will pop-up a little
>     GUI that allows you to tailor the build. It then starts
>     building .dsw and .dsp files for Microsoft, or makefiles for
>Borland.
>     You'll have to tell CMakeSetup where you've placed your VTK source
>     code, and where to build the object code and dll's
>     (we'll call it "vtkbin").
>
>  3) When CMakeSetup completes, start up msdev and load VTK.dsw.
>     Select ALL_BUILD project, and build it.
>
>
>I have unzipped the source to C:\VTK and am now trying to get the cmake
>stuff to work. I start CMakeSetup and then set the source directory to
>c:\vtk and the destination directory to c:\vtk\builds. I select Build
For
>Visual Studio. I then click
>configure as OK is grayed out.
>
>After that, I try to run one of the available examples in
>Vtk/Examples/Rendering/Tcl
>and It shows the following error:
>cant not find package vtk while executing "package require vtk"
>
>What is the Problem in the installion?
>
>
>Thanks
>
>_________________________________________________________________
>Correos más divertidos con fotos y textos increíbles en MSN 8. Pruébalo

>gratis dos meses. http://join.msn.com/?pgmarket=es-es&XAPID=45&DI=1055
>
>
>
--
********************************************
Laurent Mundeleer
Université Libre de Bruxelles (ULB)
Service des Systèmes Logiques et Numériques (SLN) CP165/57
50, Av. F.Roosevelt
1050 Bruxelles
Belgium
tel : ++32.2.650.22.97
fax : ++32.2.650.22.98
e-mail : lmundele at ulb.ac.be
********************************************


--__--__--

Message: 2
From: "Malcolm Drummond" <malcolm at geovision.co.za>
To: "vtkusers" <vtkusers at vtk.org>
Subject: Re: [vtkusers] associating datra to polydata
Date: Wed, 25 Feb 2004 16:32:34 +0200
Organization: GeoVision cc

This is a multi-part message in MIME format.

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Hi Sebastien

There is the issue of  'compound' objects: ie when you glyph data =
associated with points or when you tesselate or otherwise decompose =
concave polygons and/or polygons with internal boundaries into simpler =
primitives. In both cases, to avoid a massive duplication of data, I =
append an array that just stores indexes into the original cell-ids or =
data (which I usually keep out of the pipeline). When a pick takes =
place, the cell-id is used as an index into the stored indexes - and so
=
on to the original data.

I visualize a lot of mining layouts that use an arc/node model similar =
to many GIS. In my reader I build the polygon boundaries (internal and =
external) and then tessellate, after which I add the triangular cells to
=
the polydata. I have two arrays in the cell-data, one for the scalar =
value of interest and the other for the original polygon id, which are =
also updated as the triangles are added. I've also used this approach to
=
visualize polygon data from shapefiles and associated dBase tables.

I've used a similar technique glyphing seismic events from an access =
database. I wrote my own glyph filter but I see there is an option in =
vtkGlyph3D to store ids in the point data (which you could still get at
=
using vtkPolyData::GetCellPoints if you used a cell picker).

I think the most efficient approach is to only put data relevant to the
=
visualization into the pipelines (plus one array for indexes if =
required) - keep additional data upstream or out of the pipeline and use
=
indexing to get it when required.

HTH
Malcolm=20

----- Original Message -----=20
  From: S=E9bastien MARAUX=20
  To: vtkusers at vtk.org=20
  Sent: Tuesday, February 24, 2004 4:40 PM
  Subject: [vtkusers] associating datra to polydata


  Hello,



  I am working in GIS field, where many polygons/lines or points groups
=
are associated with data (data for points, for lines, for polygons, and
=
for general group information).

  What is the simpliest way of keeping my associated information (which
=
can be float, double, string arrays) when I convert a GIS format into a
=
vtkPolyData + ???(for associated information)

  And keep the link between information and what it is relevant to =
(points with their data, lines with their data, general group data) ?



  Seb









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<META content=3D"MSHTML 6.00.2800.1106" name=3DGENERATOR>
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             page: Section1
}
</STYLE>
</HEAD>
<BODY lang=3DFR vLink=3Dpurple link=3Dblue bgColor=3D#ffffff>
<DIV><FONT face=3DArial size=3D2>Hi Sebastien</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>There is the&nbsp;issue of =
&nbsp;'compound'=20
objects: ie when you glyph&nbsp;data associated with points&nbsp;or when
=
you=20
tesselate or otherwise decompose concave polygons and/or polygons with =
internal=20
boundaries into simpler primitives. In both cases, to avoid a massive=20
duplication of data,&nbsp;I append an array&nbsp;that just =
stores&nbsp;indexes=20
into the original cell-ids or data (which I usually keep out of the =
pipeline).=20
When a pick takes place,&nbsp;the cell-id&nbsp;is used as&nbsp;an=20
index&nbsp;into the stored indexes -&nbsp;and so on to the original=20
data.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>I visualize a lot of mining =
layouts&nbsp;that use=20
an&nbsp;arc/node model similar to&nbsp;many GIS. In my reader I build =
the=20
polygon boundaries (internal and external)&nbsp;and then tessellate, =
after which=20
I add the triangular cells to the polydata.&nbsp;I have two arrays in =
the=20
cell-data, one for the scalar value of interest&nbsp;and the other for =
the=20
original polygon id, which are also updated as the triangles are added.
=
I've=20
also&nbsp;used this approach to visualize&nbsp;polygon data&nbsp;from =
shapefiles=20
and associated dBase tables.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>I've used a =
similar&nbsp;technique&nbsp;glyphing=20
seismic events from an access database. I&nbsp;wrote my own glyph filter
=
but I=20
see there is an option in vtkGlyph3D to store ids in the point data =
(which you=20
could still get at&nbsp;using vtkPolyData::GetCellPoints if you used a =
cell=20
picker).</FONT></DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>I think the most efficient approach is
=
to only put=20
data relevant to the visualization into the pipelines (plus one array =
for=20
indexes if required)&nbsp;- keep additional data upstream or&nbsp;out of
=
the=20
pipeline and use indexing to get it when required.</FONT></DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>HTH</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Malcolm</FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV>----- Original Message ----- </DIV>
<BLOCKQUOTE dir=3Dltr=20
style=3D"PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; =
BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
  <DIV=20
  style=3D"BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>=20
  <A title=3Dmaraux at ondim.fr href=3D"mailto:maraux at ondim.fr">S=E9bastien
=
MARAUX</A>=20
  </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>To:</B> <A title=3Dvtkusers at vtk.org
=

  href=3D"mailto:vtkusers at vtk.org">vtkusers at vtk.org</A> </DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Sent:</B> Tuesday, February 24, =
2004 4:40=20
  PM</DIV>
  <DIV style=3D"FONT: 10pt arial"><B>Subject:</B> [vtkusers] associating
=
datra to=20
  polydata</DIV>
  <DIV><BR></DIV>
  <DIV class=3DSection1>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial">Hello,</SPAN></FONT></P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></FONT>&nbsp;</P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial">I am working in GIS =
field, where=20
  many polygons/lines or points groups are associated with data (data =
for=20
  points, for lines, for polygons, and for general group=20
  information).</SPAN></FONT></P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial">What is the simpliest =
way of=20
  keeping my associated information (which can be float, double, string
=
arrays)=20
  when I convert a GIS format into a vtkPolyData + ???(for associated=20
  information)</SPAN></FONT></P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial">And keep the link =
between=20
  information and what it is relevant to (points with their data, lines
=
with=20
  their data, general group data) ?</SPAN></FONT></P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></FONT>&nbsp;</P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial">Seb</SPAN></FONT></P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></FONT>&nbsp;</P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></FONT>&nbsp;</P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: Arial"></SPAN></FONT>&nbsp;</P>
  <P class=3DMsoNormal><FONT face=3DArial size=3D2><SPAN lang=3DEN-GB=20
  style=3D"FONT-SIZE: 10pt; FONT-FAMILY: =
Arial"></SPAN></FONT>&nbsp;</P></DIV></BLOCKQUOTE></BODY></HTML>

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--__--__--

Message: 3
Subject: RE: [vtkusers] memory leak in windows/mfc app
Date: Wed, 25 Feb 2004 15:58:52 +0100
From: "de Boer Ingo" <I.deBoer at polytec.de>
To: "Mathieu Malaterre" <mathieu.malaterre at kitware.com>
Cc: "Finegan Thomas-QTF001" <T.Finegan at motorola.com>,
             <vtkusers at vtk.org>

Hi,

> Please note that it has been fixed in the CVS:
> http://vtk.org/Bug/bug.php?op=3Dshow&bugid=3D138&pos=3D12
> So you can always use that code for your app.
I've seen that and tried it before, but I still have
my 5600 bytes leakage. So, I thought this hasn't been
fixed. I am still investigating on this... I am using
VTK 4.4.0

greets
  Ingo

---
Dr.-Ing. Ingo H. de Boer

Polytec GmbH
Polytec-Platz 1-7, 76337 Waldbronn, Germany
phone: ++49 7243 604 106
fax  : ++49 7243 604 255
=20

--__--__--

Message: 4
Date: Wed, 25 Feb 2004 10:14:02 -0500
From: Mathieu Malaterre <mathieu.malaterre at kitware.com>
Organization: Kitware Inc.
To: de Boer Ingo <I.deBoer at polytec.de>
Cc: vtkusers at vtk.org
Subject: Re: [vtkusers] memory leak in windows/mfc app


> I've seen that and tried it before, but I still have
> my 5600 bytes leakage. So, I thought this hasn't been
> fixed. I am still investigating on this... I am using
> VTK 4.4.0

Ingo,

             We are running valgrind/purify each night to prevent those
leakage:

http://www.paraview.org/Testing/Sites/straylight.kitwarein/Linux-g++-com
p/20040221-0100-Nightly/Purify.html
http://www.vtk.org/Testing/Sites/morva.kitware/Windows-devenv/20040225-0
300-Nightly/Purify.html

Could you please try to write a simple code that reproduce this leakage
and send it to the list ?

Thanks
Mathieu



--__--__--

Message: 5
Date: 25 Feb 2004 15:24:15 -0000
From: "david  michell" <davidmichell at rediffmail.com>
Reply-To: "david  michell" <davidmichell at rediffmail.com>
To: vtkusers at vtk.org
Subject: [vtkusers] please someone help me on this code

 This is a multipart mime message


--Next_1077722655---0-203.199.83.37-2765
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             charset=iso-8859-1
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<P>=0AHi,<BR>=0Athanks for reading.<BR>=0A<BR>=0AI have something like
this= .<BR>=0A<BR>=0AAn unstructured grid of points. The unstructured grid
has
tw= o arrays.<BR>=0A<BR>=0AI want to set glyphs for the points.<BR>=0AThe
size =
of the glyph must ceom from the array 2 and the colour of the glyph must
co= me from the array 1.<BR>=0A<BR>=0AThe code fragments are as
follows.<BR>=0A= //m_unstructuredgrid is vtkUnstructuredGrid
object<BR>=0Am_unstructuredgrid= -&gt;GetPointData()-&gt;AddArray(GlyphColourArray);<BR>=0Am_unstructured

gri= 
d-&gt;GetPointData()-&gt;AddArray(GlyphSizeArray);<BR>=0A<BR>=0Am_glyph3
D-&=
gt;SetInput(m_unstructuredgrid);<BR>=0A//m_spheresource is
vtkSphereSource =
object<BR>=0Am_glyph3D-&gt;SetSource(m_spheresource-&gt;GetOutput());<BR
>= =0Am_glyph3D-&gt;SetScaleModeToScaleByScalar();<BR>=0A<BR>=0Am_glyphmapp
er-=
&gt;SetInput(m_glyph3D-&gt;GetOutput());<BR>=0A<BR>=0Am_glyphactor-&gt;S
etM= apper(m_glyphmapper);<BR>=0A<BR>=0AThe question is how to tell VTK to
use G= lyphColourArray for the glyph colours and GlyphSizeArray for the
glyph
size= s?<BR>=0A<BR>=0AThank you,<BR>=0Adavid
michell<BR>=0A=0A</P>=0A<br><br>=0A<=
A target=3D"_blank"
HREF=3D"http://clients.rediff.com/signature/track_sig.a=
sp"><IMG
SRC=3D"http://ads.rediff.com/RealMedia/ads/adstream_nx.cgi/www.red=
iffmail.com/inbox.htm at Bottom" BORDER=3D0 VSPACE=3D0 HSPACE=3D0
HEIGHT=3D74 =
WIDTH=3D496></a>=0A
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Hi,=0Athanks for reading.=0A=0AI have something like this.=0A=0AAn
unstruct= ured grid of points. The unstructured grid has two arrays.=0A=0AI
want
to s= et glyphs for the points.=0AThe size of the glyph must ceom from the
array =
2 and the colour of the glyph must come from the array 1.=0A=0AThe code
fra= gments are as follows.=0A//m_unstructuredgrid is vtkUnstructuredGrid
object= =0Am_unstructuredgrid->GetPointData()->AddArray(GlyphColourArray);=0Am_u

nst= 
ructuredgrid->GetPointData()->AddArray(GlyphSizeArray);=0A=0Am_glyph3D->
Set= Input(m_unstructuredgrid);=0A//m_spheresource is vtkSphereSource
object=0Am= _glyph3D->SetSource(m_spheresource->GetOutput());=0Am_glyph3D->SetScaleM

ode= 
ToScaleByScalar();=0A=0Am_glyphmapper->SetInput(m_glyph3D->GetOutput());
=0A= =0Am_glyphactor->SetMapper(m_glyphmapper);=0A=0AThe question is how to
tell=  VTK to use GlyphColourArray for the glyph colours and GlyphSizeArray
for t= he glyph sizes?=0A=0AThank you,=0Adavid michell=0A
--Next_1077722655---0-203.199.83.37-2765--


--__--__--

Message: 6
Date: Wed, 25 Feb 2004 10:39:52 -0500 (EST)
From: Weiguang Guan <guanw at rhpcs.mcmaster.ca>
To: vtkusers at vtk.org
Subject: [vtkusers] Texture-mapping based volume rendering

Hi everyone,

Does vtk implement texture mapping based volume rendering which utilizes

modern graphics card's 3D texture mapping capability? It could make
volume
rendering much faster without using special hardware (like VolumePro).
Has anyone made a performace comparison of different rendering
techniques (in terms of sec or ms on 256 cubic volume)? Thanks.

Weiguang

--
========================================================
Weiguang Guan, Research Engineer
RHPCS, McMaster University
========================================================


--__--__--

Message: 7
From: "Ted Vu" <lost_bits1110 at hotmail.com>
To: vtkusers at vtk.org
Date: Wed, 25 Feb 2004 15:48:12 +0000
Subject: [vtkusers] Smoothing

Good morning

I have a vtkPolyData (one big parallelogram) which consists of many
parallelograms (I got this from vtkPlaneSource) and I have color coded
each
of the cells to some color corresponding to a scalar

But this looks very 'pixelated'
I cannot increase teh number of cells/resolution (i.e the number of
smaller
parallelograms in my big parallelogram) becaus this significantly
reduces
speed etc..

So I tried using vtkSmoothPolyDataFilter by doing teh following:

       Smoother = vtkSmoothPolyDataFilter::New();
             Smoother->SetNumberOfIterations(100);
             Smoother->FeatureEdgeSmoothingOn();
             Smoother->SetInput(myPolyData->GetOutput());

but this makes absolutely no difference

I also treid teh same with Smoother =
vtkWindowedSincPolyDataFilter::New();

So how can I sort of 'blur' all these parallelograms so it doesnt look
so
pixelated?

_________________________________________________________________
Get fast, reliable access with MSN 9 Dial-up. Click here for Special
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--__--__--

Message: 8
Date: Wed, 25 Feb 2004 16:56:11 +0100
From: Uwe Rempler <rempler at mechbau.uni-stuttgart.de>
To: vtkusers at vtk.org
Subject: [vtkusers] Using multiple Vectors

hi list,

i'm looking for a way to visualize more than one vectorarrow per point
(displacement-vector / another-vector) - for example somehow like this:

#-----------------------------------------------------------------------
--------

firstVectorArray = vtkFloatArray()
firstVectorArray.SetName('FIRST')
secondVectorArray = vtkFloatArray()
secondVectorArray.SetName('SECOND')
unstructGrid = vtkUnstructuredGrid()
attribute = vtkAssignAttribute()
arrow = vtkArrowSource()
glyph = vtkGlyph3D()
mapper = vtkPolyDataMapper()
actor = vtkActor()
# just imagine the grid and the vetorarrays are filled with lots of data
;-)

unstructGrid.GetPointData().AddArray(firstVectorArray)
unstructGrid.GetPointData().AddArray(secondVectorArray)

attribute.SetInput(unstructGrid.GetOutput())
attribute.Assign('FIRST', 'VECTORS',  'POINT_DATA')      << here's the
problem: either 'FIRST' or 'SECOND'
attribute.Assign('SECOND', 'VECTORS',  'POINT_DATA')      << array but
not both at the same time...
attribute.Update()

glyph.SetInput(attribute.GetOutput())
glyph.SetSource(arrow.GetOutput())

mapper.SetInput(glyph.GetOutput())
actor.SetMapper(mapper)

etc...
#-----------------------------------------------------------------------
--------


i know that this isn't working cause there was already a question about
how to handle more than one vector simultaneous:
http://public.kitware.com/pipermail/vtkusers/2002-June/011932.html
and the answer said that "there can be only one active "attribute" of
each type (scalar, vector, normal etc.) at one time" when using
AddArray()...
does anybody know a way of showing two vectors at the same time? or
should i just add another actor showing the second vector array
arrows...?

greetings
uwe

--__--__--

Message: 9
From: =?iso-8859-1?Q?S=E9bastien_MARAUX?= <maraux at ondim.fr>
To: <vtkusers at vtk.org>
Date: Wed, 25 Feb 2004 17:06:12 +0100
Subject: [vtkusers] surface mesh / terrain decimation

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Hello,



Is there any alogrithm implemented in VTk which could handle a several
millions points terrain mesh and decimate it to a few thousands points ?



I am expecting algorithms such as quad tree, Delaunay point insertion
method or others.

vtkDecimatePro does not seem to give as good results as I expected.



I would also appreciate any algorithm idea that I could implement.

I am currently only using subsampling for decimation.



Sebastien MARAUX


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<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Hello,</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>&nbsp;</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>Is there any alogrithm implemented in VTk =
which could
handle a several millions points terrain mesh and decimate it to a few
thousands points ?</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>&nbsp;</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I am expecting algorithms such as quad tree, =
Delaunay
point insertion method or others.</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>vtkDecimatePro does not seem to give as good =
results
as I expected.</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>&nbsp;</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I would also appreciate any algorithm idea =
that I could
implement.</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>I am currently only using subsampling for =
decimation.</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB =
style=3D'font-size:
10.0pt;font-family:Arial'>&nbsp;</span></font></p>

<p class=3DMsoNormal><font size=3D2 face=3DArial><span =
style=3D'font-size:10.0pt;
font-family:Arial'>Sebastien MARAUX</span></font></p>

</div>

</body>

</html>

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