[vtkusers] Problem with vtkPolyLine width greater than 20

[Stefan Köhnen]

Thanks, that is exactly what we need. Especially this part "This is
helpful because when you zoom the camera, the thickness of a line
remains constant, while the thickness of a tube varies."

I will look into it. Thanks for your reply Jothy.

But just to clarify, there is a limit for the width of a vtkPolyLine?

Greetings,

Stefan


2012/4/26 Jothybasu Selvaraj <jothybasu at gmail.com>:
> If you want such a thick line, why don't you use vtkTubeFilter?
>
> Jothy
>
> On Thu, Apr 26, 2012 at 1:11 PM, Stefan Köhnen <stefan.khnen at googlemail.com>
> wrote:
>>
>> Hello,
>>
>> I have a problem while trying to increase the width of a vtkPolyLine.
>> No matter what I try, the width never seems to become bigger for
>> values above 20.
>>
>> For values below 20, the method SetLineWidth works as expected.
>>
>> My question is if there is a limitation that prevents me to increase
>> the width further or is there an error in my implementation.
>>
>> To explain my problem better I modified the PolyLine-Example.
>> I added SetLineWidth for the vtkProperty of the vtkActor.
>>
>>
>> Greetings,
>>
>> Stefan Köhnen
>>
>> Here is the code:
>>
>> #include <vtkVersion.h>
>> #include <vtkSmartPointer.h>
>> #include <vtkCellArray.h>
>> #include <vtkCellData.h>
>> #include <vtkDoubleArray.h>
>> #include <vtkPoints.h>
>> #include <vtkPolyLine.h>
>> #include <vtkPolyData.h>
>> #include <vtkPolyDataMapper.h>
>> #include <vtkActor.h>
>> #include <vtkRenderWindow.h>
>> #include <vtkRenderer.h>
>> #include <vtkRenderWindowInteractor.h>
>> #include <vtkProperty.h>
>>
>> int main(int, char *[])
>> {
>>  // Create five points.
>>  double origin[3] = {0.0, 0.0, 0.0};
>>  double p0[3] = {1.0, 0.0, 0.0};
>>  double p1[3] = {0.0, 1.0, 0.0};
>>  double p2[3] = {0.0, 1.0, 2.0};
>>  double p3[3] = {1.0, 2.0, 3.0};
>>
>>  // Create a vtkPoints object and store the points in it
>>  vtkSmartPointer<vtkPoints> points =
>>    vtkSmartPointer<vtkPoints>::New();
>>  points->InsertNextPoint(origin);
>>  points->InsertNextPoint(p0);
>>  points->InsertNextPoint(p1);
>>  points->InsertNextPoint(p2);
>>  points->InsertNextPoint(p3);
>>
>>  vtkSmartPointer<vtkPolyLine> polyLine =
>>    vtkSmartPointer<vtkPolyLine>::New();
>>  polyLine->GetPointIds()->SetNumberOfIds(5);
>>  for(unsigned int i = 0; i < 5; i++)
>>    {
>>    polyLine->GetPointIds()->SetId(i,i);
>>    }
>>
>>  // Create a cell array to store the lines in and add the lines to it
>>  vtkSmartPointer<vtkCellArray> cells =
>>    vtkSmartPointer<vtkCellArray>::New();
>>  cells->InsertNextCell(polyLine);
>>
>>  // Create a polydata to store everything in
>>  vtkSmartPointer<vtkPolyData> polyData =
>>    vtkSmartPointer<vtkPolyData>::New();
>>
>>  // Add the points to the dataset
>>  polyData->SetPoints(points);
>>
>>  // Add the lines to the dataset
>>  polyData->SetLines(cells);
>>
>>  // Setup actor and mapper
>>  vtkSmartPointer<vtkPolyDataMapper> mapper =
>>    vtkSmartPointer<vtkPolyDataMapper>::New();
>> #if VTK_MAJOR_VERSION <= 5
>>  mapper->SetInput(polyData);
>> #else
>>  mapper->SetInputData(polyData);
>> #endif
>>
>>  vtkSmartPointer<vtkActor> actor =
>>    vtkSmartPointer<vtkActor>::New();
>>  actor->SetMapper(mapper);
>>
>>
>>  ////////////////////////////////////////////////////////////////////////////
>>  // Here is the explained change - Set width of line
>>  actor->GetProperty()->SetLineWidth(30.0f);
>>
>>  ////////////////////////////////////////////////////////////////////////////
>>
>>
>>  // Setup render window, renderer, and interactor
>>  vtkSmartPointer<vtkRenderer> renderer =
>>    vtkSmartPointer<vtkRenderer>::New();
>>  vtkSmartPointer<vtkRenderWindow> renderWindow =
>>    vtkSmartPointer<vtkRenderWindow>::New();
>>  renderWindow->AddRenderer(renderer);
>>  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
>>    vtkSmartPointer<vtkRenderWindowInteractor>::New();
>>  renderWindowInteractor->SetRenderWindow(renderWindow);
>>  renderer->AddActor(actor);
>>
>>  renderWindow->Render();
>>  renderWindowInteractor->Start();
>>
>>  return EXIT_SUCCESS;
>> }
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>
>
>
>
> --
> Jothy
>