[vtkusers] How To Texture Map a patch with vtkGlobeSource

Joey Mukherjee joeymu at gmail.com
Thu Nov 4 11:34:00 EDT 2010


Thanks for posting this example Aashish!

I have some NetCDF data files that I would like to overlay over the Earth
and be able to extract subsets from them and the like.  To get this same
type of visualization, can I make use of the Geo classes?   Does the have to
be a texture map or can I use any kind of regularized image data?

Thanks,
Joey

On Thu, Nov 4, 2010 at 8:25 AM, Aashish Chaudhary <
aashish.chaudhary at kitware.com> wrote:

>
>
> On Thu, Nov 4, 2010 at 12:43 AM, Donny <donnyz at charter.net> wrote:
>
>>  I just figured out that the vtkGlobeSource already converts the lat,lon
>> points to world points in meters from a defined origin that can be set via
>> SetOrigin().
>>
>> Problem solved. Thanks Aashish!!!
>>
> Make sense. Thats why I was not so sure what you meant by origin (I thought
> you are referring to Datum).
>
> You are welcome. In fact I created a new test (cleaned version of the code
> I sent earlier) and merged into VTK.
>
> commit:
>
> http://www.vtk.org/gitweb?p=VTK.git;a=commit;h=8cf560c2351ff457b0156b3cbc5f5cb4d5414401
>
>
> <http://www.vtk.org/gitweb?p=VTK.git;a=commit;h=8cf560c2351ff457b0156b3cbc5f5cb4d5414401>
> Thanks,
>
>
>
>>
>> -----Original Message-----
>> *From:* Donny [mailto:donnyz at charter.net]
>> *Sent:* Wednesday, November 03, 2010 9:40 PM
>> *To:* 'Aashish Chaudhary'
>> *Cc:* 'vtkusers at vtk.org'
>> *Subject:* RE: [vtkusers] How To Texture Map a patch with vtkGlobeSource
>>
>>
>>
>> Wow. Thanks Aashish.
>>
>> It would be nice if vtkTextureMapToSphere would do this mapping correctly.
>>
>> I have one question about implementing this. I need to convert the lat lon
>> coordinates to meters from a defined origin. I think vtkGeoAssignCoordinates
>> will do the job. Can I use this filter after the texture coordinates are set
>> using your code?
>>
>>
>>
>> -----Original Message-----
>>
>> *From:* Aashish Chaudhary [mailto:aashish.chaudhary at kitware.com]
>> *Sent:* Wednesday, November 03, 2010 1:05 AM
>> *To:* Donny
>> *Cc:* vtkusers at vtk.org
>> *Subject:* Re: [vtkusers] How To Texture Map a patch with vtkGlobeSource
>>
>>
>>
>> Hi Donny,
>>
>>
>>
>> I didn't get the time to  clean this code but it will work for you ..
>>
>>
>>
>> I just modified a test (and hence it look bit different)
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> #include <vtkGlobeSource.h>
>>
>> #include <vtkPolyDataMapper.h>
>>
>> #include <vtkActor.h>
>>
>> #include <vtkPointData.h>
>>
>> #include <vtkDoubleArray.h>
>>
>> #include "vtkBMPReader.h"
>>
>> #include "vtkCamera.h"
>>
>> #include "vtkGeoAlignedImageRepresentation.h"
>>
>> #include "vtkGeoAlignedImageSource.h"
>>
>> #include "vtkGeoEdgeStrategy.h"
>>
>> #include "vtkGeoFileImageSource.h"
>>
>> #include "vtkGeoFileTerrainSource.h"
>>
>> #include "vtkGeoGlobeSource.h"
>>
>> #include "vtkGeoProjection.h"
>>
>> #include "vtkGeoProjectionSource.h"
>>
>> #include "vtkGeoRandomGraphSource.h"
>>
>> #include "vtkGeoSphereTransform.h"
>>
>> #include "vtkGeoTerrain.h"
>>
>> #include "vtkGeoTerrainNode.h"
>>
>> #include "vtkGeoTerrain2D.h"
>>
>> #include "vtkGeoTransform.h"
>>
>> #include "vtkGeoView.h"
>>
>> #include "vtkGeoView2D.h"
>>
>> #include "vtkGraphLayoutView.h"
>>
>> #include "vtkJPEGReader.h"
>>
>> #include "vtkRegressionTestImage.h"
>>
>> #include "vtkRenderedGraphRepresentation.h"
>>
>> #include "vtkRenderer.h"
>>
>> #include "vtkRenderWindow.h"
>>
>> #include "vtkRenderWindowInteractor.h"
>>
>> #include "vtkSmartPointer.h"
>>
>> #include "vtkStdString.h"
>>
>> #include "vtkTestUtilities.h"
>>
>> #include "vtkTIFFReader.h"
>>
>> #include "vtkViewTheme.h"
>>
>> #include "vtkViewUpdater.h"
>>
>> #include <vtksys/SystemTools.hxx>
>>
>>
>>
>> #define VTK_CREATE(type,name) \
>>
>>   vtkSmartPointer<type> name = vtkSmartPointer<type>::New();
>>
>> int TestGeoView(int argc, char* argv[])
>>
>> {
>>
>>   char* image = vtkTestUtilities::ExpandDataFileName(
>>
>>     argc, argv, "Data/usa_image.jpg");
>>
>>   vtkStdString imageFile = image;
>>
>>   vtkSmartPointer<vtkJPEGReader> reader =
>>
>>     vtkSmartPointer<vtkJPEGReader>::New();
>>
>>   reader->SetFileName(imageFile.c_str());
>>
>>   reader->Update();
>>
>>   double latRange[]  = {24, 50};
>>
>>   double longRange[] = {-126, -66};
>>
>>   VTK_CREATE(vtkGlobeSource, globeSource);
>>
>>   globeSource->SetStartLatitude(latRange[0]);
>>
>>   globeSource->SetEndLatitude(latRange[1]);
>>
>>   globeSource->SetStartLongitude(longRange[0]);
>>
>>   globeSource->SetEndLongitude(longRange[1]);
>>
>>   globeSource->Update();
>>
>>   VTK_CREATE(vtkActor, actor);
>>
>>   VTK_CREATE(vtkPolyDataMapper, mapper);
>>
>>   vtkDoubleArray* newArray (vtkDoubleArray::New());
>>
>>   newArray->SetNumberOfComponents(2);
>>
>>   vtkDoubleArray* array = vtkDoubleArray::SafeDownCast(globeSource->GetOutput(0)->GetPointData()->GetAbstractArray("LatLong"));
>>
>>   double range[] = { (latRange[1] -latRange[0]),
>>
>>                      (longRange[1] - longRange[0]) };
>>
>>   double val[2];
>>
>>   double newVal[2];
>>
>>   for(int i=0; i < array->GetNumberOfTuples(); ++i)
>>
>>     {
>>
>>      array->GetTupleValue(i, val);
>>
>>      newVal[1] = (val[0] - latRange[0])  / range[0];
>>
>>      newVal[0] = (val[1] - longRange[1]) / range[1];
>>
>>      newArray->InsertNextTuple(newVal);
>>
>>     }
>>
>>   globeSource->GetOutput(0)->GetPointData()->SetTCoords(newArray);
>>
>>   mapper->SetInput( globeSource->GetOutput(0) );
>>
>>   actor->SetMapper(mapper);
>>
>>   VTK_CREATE(vtkTexture, texture);
>>
>>   texture->SetInput(reader->GetOutputDataObject(0));
>>
>>   actor->SetTexture(texture);
>>
>>   VTK_CREATE(vtkRenderWindow, renWin);
>>
>>   VTK_CREATE(vtkRenderWindowInteractor, renWinInt);
>>
>>   VTK_CREATE(vtkRenderer, ren);
>>
>>   ren->AddActor(actor);
>>
>>   renWin->AddRenderer(ren);
>>
>>   renWinInt->SetRenderWindow(renWin);
>>
>>   renWin->SetSize(400,400);
>>
>>   renWin->Render();
>>
>>   renWinInt->Initialize();
>>
>>   renWin->Render();
>>
>>   int retVal = vtkRegressionTestImage( renWin );
>>
>>   if( retVal == vtkRegressionTester::DO_INTERACTOR)
>>
>>     {
>>
>>     renWinInt->Start();
>>
>>     }
>>
>>   return 0;
>>
>> }
>>
>>
>>
>> Attached is the screenshot of my test..
>>
>>
>>
>>
>>
>> On Tue, Nov 2, 2010 at 10:56 PM, Donny <donnyz at charter.net> wrote:
>>
>> Thanks for the help Aashish. I have attached 3 image files, one with the
>> AutomaticSphereGenerationOff() set on the vtkTextureMapToSphere object and
>> one with AutomaticSphereGenerationOn(). The third image is not a
>> screenshot,
>> it is the actual texture I am trying to map to the patch.  The only
>> settings
>> I set on the vtkGlobeSource are :
>> gs->SetStartLatitude(24.0);
>> gs->SetEndLatitude(50.0);
>> gs->SetStartLongitude(-126.0);
>> gs->SetEndLongitude(-66.0);
>>
>> As you can see the GlobeSource patch geometry is rendering as intended,
>> but
>> the texture is not appearing correctly.
>>
>>
>> "you can have
>>
>> tx = asin(Nx)/PI  + 0.5
>> ty = asin(Ny)/PI + 0.5"
>>
>> Is there a filter that will perform this mapping for me?
>>
>> Thanks.
>>
>>
>> -----Original Message-----
>> From: Aashish Chaudhary [mailto:aashish.chaudhary at kitware.com]
>> Sent: Tuesday, November 02, 2010 10:11 AM
>> To: Donny
>> Cc: vtkusers at vtk.org
>> Subject: Re: [vtkusers] How To Texture Map a patch with vtkGlobeSource
>>
>> Hi Donny,
>> - Show quoted text -
>> I have not used vtkTextureMapToSphere myself but can you try to
>> generate your own texture coordinates? globe source does produce
>> normals and in its very simplistic approach  ...
>>
>> you can have
>>
>> tx = asin(Nx)/PI  + 0.5
>> ty = asin(Ny)/PI + 0.5
>>
>> In a shader you can do it easily.  Not sure why vtkTextureMapToSphere
>> didn't work. Will find out.
>>
>> Can you post a snapshot?
>>
>> On Tue, Nov 2, 2010 at 12:01 AM, Donny <donnyz at charter.net> wrote:
>> > I have created a globe patch with vtkGlobeSource for the general area of
>> the
>> > United States (Lat 24 to 50 Deg, Lon -126 to -66 Deg.) using
>> > SetLatitudeStart, SetLatitudeEnd ... I also have a .bmp image that
>> > corresponds to these extents and cannot find a filter to generate the
>> > texture coordinates for this patch so I can texture it. I tried
>> > vtkTextureMapToSphere and turned auto generate sphere to off but it only
>> > displayed a small portion of the image onto the patch. How can I
>> generate
>> > the texture coordinates for a patch such as this?
>> >
>> >
>> >
>> > Thanks.
>> >
>> >
>> >
>> > Donny Zimmerman
>> >
>> >
>> >
>> > _______________________________________________
>> > Powered by www.kitware.com
>> >
>> > Visit other Kitware open-source projects at
>> > http://www.kitware.com/opensource/opensource.html
>> >
>> > Please keep messages on-topic and check the VTK FAQ at:
>> > http://www.vtk.org/Wiki/VTK_FAQ
>> >
>> > Follow this link to subscribe/unsubscribe:
>> > http://www.vtk.org/mailman/listinfo/vtkusers
>> >
>> >
>>
>>
>>
>> --
>> | Aashish Chaudhary
>> | R&D Engineer
>> | Kitware Inc.
>> | www.kitware.com
>>
>>
>>
>>
>> --
>> | Aashish Chaudhary
>> | R&D Engineer
>> | Kitware Inc.
>> | www.kitware.com
>>
>
>
>
> --
> | Aashish Chaudhary
> | R&D Engineer
> | Kitware Inc.
> | www.kitware.com
>
> _______________________________________________
> Powered by www.kitware.com
>
> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
>
> Please keep messages on-topic and check the VTK FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
>
> Follow this link to subscribe/unsubscribe:
> http://www.vtk.org/mailman/listinfo/vtkusers
>
>
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