[vtkusers] Fwd: Re:AW: vtkContourFilternotworkingonvtkStructuredGrid
Sebastian Gatzka
sebastian.gatzka at stud.tu-darmstadt.de
Fri Mar 12 07:34:43 EST 2010
It's finite-volume-calculation
<http://en.wikipedia.org/wiki/Finite_volume_method> scalar data, which
is - as a matter of fact - stored at the cell centers.
Maybe I have to interpolate to the points if contour filter doesn't work
on cell data?!
Am 12.03.2010 13:28, schrieb Rakesh Patil:
>
> Well,
>
> What type of data is it..?? Is it a mesh or set of points..?? Why you
> want to set scalars for cell data..?? If you change this to set
> scalars to points it may work i guess.. Because, for me it works fine
> with points and only thing which comes in my mind is that, contour
> filter works only with point data and not cell data..
>
> Any way to make contour filter work with cell data guys..??
>
> Thanks
>
> Regards
> Rakesh Patil
>
>
> ---------- Original message ----------
> From:Sebastian Gatzka< sebastian.gatzka at stud.tu-darmstadt.de >
> Date: 12 Mar 10 16:35:42
> Subject: Re: [vtkusers] Fwd: Re:AW:
> vtkContourFilternotworkingonvtkStructuredGrid
> To: vtkusers
>
> I have checked it maybe a hundrert times.
> I have tried different ranges, different numbers of surfaces,
> GenerateValues(), SetValue() even different colors (in case it
> collides with the color).
>
> And yes maybe my data has some problem - but I have absolutley NO
> idea what kind of.
> The scalar data is properly displayed on a cutting plane, but I
> can't create iso surfaces.
>
> Am 12.03.2010 11:59, schrieb Rakesh Patil:
>>
>> Try once again... Check code properly.. It should work.. else
>> your data may be having some problem..
>>
>> Thanks
>>
>> Regards
>> Rakesh Patil
>>
>>
>> ---------- Original message ----------
>> From:Sebastian Gatzka< sebastian.gatzka at stud.tu-darmstadt.de >
>> Date: 12 Mar 10 15:57:21
>> Subject: Re: [vtkusers] Fwd: Re:AW: vtkContourFilter
>> notworkingonvtkStructuredGrid
>> To: vtkusers
>>
>> Yes. Of Course I tried that.
>> Nothing changes.
>>
>> Am 12.03.2010 11:19, schrieb Rakesh Patil:
>>> Hi,
>>>
>>> Have you tried implementing what i told you.???
>>>
>>> scalarIsoSurface->GenerateValues( 10, sGrid->GetScalarRange() );
>>>
>>> this will solve your problem... As i told u before, there is
>>> no other prob i could figure out other than this..
>>> GenerateValues takes three parameters, i.e.
>>>
>>> 1. Number of contour lines,
>>> 2. min. value(of range)
>>> 3. max value(of range)
>>>
>>> It also takes two parameters.. in this case 2nd parameter is
>>> double array consisting two elements..
>>>
>>> Thanks
>>>
>>> Regards
>>> Rakesh Patil
>>>
>>>
>>> ---------- Original message ----------
>>> From:Sebastian Gatzka<
>>> sebastian.gatzka at stud.tu-darmstadt.de >
>>> Date: 12 Mar 10 15:40:22
>>> Subject: Re: [vtkusers] Fwd: Re:AW: vtkContourFilter not
>>> workingonvtkStructuredGrid
>>> To: vtkusers
>>>
>>> Hi again.
>>>
>>> Attached you will find the code that should produce the
>>> iso surface, but displays nothing.
>>> I even tried to apply the vtkAssignAttribute
>>> frinxor at gmail.com suggested ...
>>> Nothing changes.
>>>
>>> Hope you will find the mistake.
>>> Have a nice day.
>>> Sebastian
>>>
>>> Am 10.03.2010 15:50, schrieb Rakesh Patil:
>>>>
>>>> Well, i dont think anything is wrong
>>>>
>>>> According to this,
>>>>
>>>> http://www.vtk.org/doc/nightly/html/classvtkContourFilter.html
>>>>
>>>> vtkContourFilter is a filter that takes as input any
>>>> dataset and generates on output isosurfaces and/or
>>>> isolines. So that is not a problem..
>>>>
>>>> Can u just get you final code what u have coded..??
>>>>
>>>> Thanks
>>>>
>>>> Regards
>>>> Rakesh Patil
>>>>
>>>>
>>>> ---------- Original message ----------
>>>> From:Sebastian Gatzka<
>>>> sebastian.gatzka at stud.tu-darmstadt.de >
>>>> Date: 10 Mar 10 17:43:19
>>>> Subject: [vtkusers] Fwd: Re:AW: vtkContourFilter
>>>> not working onvtkStructuredGrid
>>>> To: vtkusers at vtk.org
>>>>
>>>> No, this doesn't work out.
>>>> I put Update()'s at every (possible) object but
>>>> nothing happens.
>>>>
>>>> Even chaning SetValue() and GenerateValues()
>>>> doesn't change that.
>>>> So maybe there is something wrong with the data?!
>>>>
>>>> I have a structured grid (called sGrid) and the
>>>> scalar values are defined at the cell centers:
>>>>
>>>> sGrid->GetCellData()->SetScalars(T);
>>>>
>>>> But I just pass the sGrid to the vtkContourFilter
>>>>
>>>> vtkContourFilter *scalarIsoSurface
>>>> vtkContourFilter::New();
>>>> scalarIsoSurface->SetInput(sGrid);
>>>>
>>>> May this be the problem?
>>>>
>>>>
>>>> -------- Original-Nachricht --------
>>>> Betreff: Re:AW: [vtkusers] vtkContourFilter not
>>>> working on vtkStructuredGrid
>>>> Datum: Sat, 06 Mar 2010 09:34:59 +0530
>>>> Von: Rakesh Patil <rakeshthp at in.com>
>>>> Antwort an: Rakesh Patil <rakeshthp at in.com>
>>>> An: Sebastian Gatzka
>>>> <sebastian.gatzka at stud.tu-darmstadt.de>
>>>>
>>>>
>>>>
>>>> Hi Sebastian,
>>>>
>>>> I see there is a small mistake over there in your
>>>> code..
>>>>
>>>> As far as my knowledge is concerned,
>>>>
>>>> scalarIsoSurface->GenerateValues(0,0.1);
>>>>
>>>> This statement should produce error. Coz, according
>>>> to the documentation given here
>>>>
>>>> http://www.vtk.org/doc/release/5.4/html/a00323.html
>>>>
>>>> GenerateValues takes two parameters if and only if
>>>> second parameter is a double array comprising of
>>>> two elements min and max range.
>>>>
>>>> Even if this code executes without any error, then
>>>> also no output will be produced, because the first
>>>> argument you are passing is 0. First parameter
>>>> tells the number of contours to be generated,
>>>> Second parameter tells within what range these
>>>> contours should be plotted.
>>>>
>>>> What i guess is, either you change it that
>>>> statement t o
>>>>
>>>> scalarIsoSurface->SetValue(0, 0.1);
>>>>
>>>> or
>>>>
>>>> scalarIsoSurface->GenerateValues( n,
>>>> sGrid->GetScalarRange() );
>>>>
>>>> where n is number of lines you want, say 1, 5, 10,
>>>> 12... whatever...
>>>>
>>>> And then say update..
>>>>
>>>> Am i correct David Sir..??
>>>>
>>>> Thanks
>>>>
>>>> Regards
>>>>
>>>> Rakesh Patil
>>>>
>>>>
>>>> ---------- Original message ----------
>>>> From:"Sebastian Gatzka"<
>>>> sebastian.gatzka at stud.tu-darmstadt.de >
>>>> Date: 05 Mar 10 22:50:50
>>>> Subject: AW: [vtkusers] vtkContourFilter not
>>>> working on vtkStructuredGrid
>>>> To: "'Rakesh Patil'"
>>>>
>>>> Hm. The ->Update() did not work out.
>>>>
>>>> What can be wrong? How can the data be not fed
>>>> correctly?
>>>>
>>>> *Von:* Rakesh Patil [mailto:rakeshthp at in.com]
>>>> *Gesendet:* Freitag, 5. M¤rz 2010 16:25
>>>> *An:* David Doria
>>>> *Cc:* Sebastian Gatzka; vtkusers at vtk.org
>>>> *Betreff:* Re: [vtkusers] vtkContourFilter not
>>>> working on vtkStructuredGrid
>>>>
>>>>
>>>> Ya, I had also done the same mistake... I had
>>>> ommitted that update statement.. By putting
>>>> that update statement is should definitley
>>>> work.. (only if data is fed correctly)
>>>>
>>>>
>>>> ---------- Original message ----------
>>>> From:David Doria< daviddoria+vtk at gmail.com >
>>>> Date: 05 Mar 10 19:26:03
>>>> Subject: Re: [vtkusers] vtkContourFilter not
>>>> working on vtkStructuredGrid
>>>> To: Sebastian Gatzka
>>>>
>>>> On Fri, Mar 5, 2010 at 8:41 AM, Sebastian
>>>> Gatzka <sebastian.gatzka at stud.tu-darmstadt.de
>>>> <mailto:sebastian.gatzka at stud.tu-darmstadt.de>>
>>>> wrote:
>>>>
>>>> Hello.
>>>>
>>>> I really can't tell why my code is not
>>>> gernerating the iso-surface.
>>>> I have a structured grid (sGrid) filled with
>>>> scalars.
>>>>
>>>> I call the contour filter
>>>>
>>>> vtkContourFilter *scalarIsoSurface
>>>> vtkContourFilter::New();
>>>> scalarIsoSurface->SetInput(sGrid);
>>>> scalarIsoSurface->GenerateValues(0,0.1);
>>>>
>>>> Compute the normal
>>>>
>>>> vtkPolyDataNormals *sGridPolyDataNormal
>>>> vtkPolyDataNormals::New();
>>>> sGridPolyDataNormal->SetInput(scalarIsoSurface->GetOutput());
>>>>
>>>> Put them into a poly data mapper
>>>>
>>>> vtkPolyDataMapper *scalarIsoSurfaceMapper
>>>> vtkPolyDataMapper::New();
>>>> scalarIsoSurfaceMapper->SetInput(sGridPolyDataNormal->GetOutput());
>>>>
>>>> and into an actor
>>>>
>>>> vtkActor *scalarIsoSurfaceActor = vtkActor::New();
>>>> scalarIsoSurfaceActor->SetMapper(scalarIsoSurfaceMapper);
>>>>
>>>> which is passed on to the scene
>>>>
>>>> ren1->AddActor(scalarIsoSurfaceActor);
>>>>
>>>> and NOTHING happens.
>>>>
>>>> Any ideas what I have missed, or whats wrong?
>>>>
>>>> Sebastian
>>>>
>>>> You probably have a call to Render() after the
>>>> code you sent us, which I believe updates the
>>>> whole pipeline. Whenever I have something that
>>>> is totally empty, I go back and put an Update()
>>>> call on every object that is updatable.
>>>>
>>>> scalarIsoSurface->GenerateValues(0,0.1);
>>>>
>>>> scalarIsoSurface->Update();
>>>>
>>>> before I dig too deep.
>>>>
>>>> If that doesn't change anything, try to create
>>>> a demo involving some simple data (using a
>>>> vtk*Source if you can, so we can reproduce it
>>>> without needing your dataset). Then send us the
>>>> smallest compilable code that demonstrates the
>>>> problem.
>>>>
>>>>
>>>> Thanks,
>>>>
>>>> David
>>>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20100312/c2a1b380/attachment.htm>
More information about the vtkusers
mailing list