# \[VTK8.9\] vtkCutter not show scalar information

**URL:** https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662
**Category:** Support
**Created:** [February 20, 2020, 3:36am UTC](https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662 "2020-02-20T03:36:52Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Yue\_JIN](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yue_jin/32/1228_2.png) [@Yue\_JIN](https://discourse.vtk.org/u/Yue_JIN)
#### Post date: [February 20, 2020, 3:36am UTC](https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662/1 "2020-02-20T03:36:52Z")

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Hi everybody, I use vtkCutter to show a section of an unstructuredgrid. My code works well in vtk 8.2. But in vtk 8.9, the actor of vtkCutter becomes white like shown in the picture attached. All these actors are rendered in QVTKOpenGLNativeWidget.

What may cause this issue?

 ![vktcutter](https://discourse.vtk.org/uploads/default/original/2X/7/7229a84d17dd0498e4be1b4617233774d2f52e4b.png)

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### Author: ![Yue\_JIN](https://discourse.vtk.org/user_avatar/discourse.vtk.org/yue_jin/32/1228_2.png) [@Yue\_JIN](https://discourse.vtk.org/u/Yue_JIN)
#### Post date: [February 20, 2020, 8:24am UTC](https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662/2 "2020-02-20T08:24:17Z")

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I can reproduce this issue in a very simple example. VTK 8.2 stills works well, but VTK 8.9 has the same problem. Maybe a bug?

 ![QQ浏览器截图20200220160739](https://discourse.vtk.org/uploads/default/original/2X/6/6d2d6fc7590d15ff26ab94cc338fc920c9ae52bf.png)  
Here is my code  
#include \<vtkSmartPointer.h\>

```
#include <vtkActor.h>
#include <vtkDataSetMapper.h>
#include <vtkPolyDataMapper.h>
#include <vtkMath.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkStructuredGrid.h>
#include <vtkUnstructuredGrid.h>
#include <vtkCutter.h>
#include <vtkDoubleArray.h>
#include <vtkPointData.h>
#include <vtkAppendFilter.h>
#include <vtkPlane.h>

int main(int, char *[])
{
  // Create a grid
  vtkSmartPointer<vtkStructuredGrid> structuredGrid =
vtkSmartPointer<vtkStructuredGrid>::New();

  vtkSmartPointer<vtkPoints> points =
vtkSmartPointer<vtkPoints>::New();

  vtkSmartPointer<vtkDoubleArray> dataArray =
  vtkSmartPointer<vtkDoubleArray>::New();

  unsigned int numi = 2;
  unsigned int numj = 2;
  unsigned int numk = 5;

  for (unsigned int k = 0; k < numk; k++)
  {
  for (unsigned int n = 0; n < 4; n++)
  {
      dataArray->InsertNextValue(k*0.2);
  }
  }

  for(unsigned int k = 0; k < numk; k++)
  {
for(unsigned int j = 0; j < numj; j++)
{
  for(unsigned int i = 0; i < numi; i++)
  {
    points->InsertNextPoint(i, j, k);
  }
}
  }

  // Specify the dimensions of the grid
  structuredGrid->SetDimensions(numi, numj, numk);
  structuredGrid->SetPoints(points);
  structuredGrid->GetPointData()->SetScalars(dataArray);

  // Create a mapper and actor
  vtkSmartPointer<vtkDataSetMapper> mapper =
vtkSmartPointer<vtkDataSetMapper>::New();
  mapper->SetInputData(structuredGrid);
  vtkSmartPointer<vtkActor> actor =
vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);

  vtkSmartPointer<vtkStructuredGrid> structuredGrid2 =
  vtkSmartPointer<vtkStructuredGrid>::New();
  vtkSmartPointer<vtkPoints> points2 =
  vtkSmartPointer<vtkPoints>::New();
   for (unsigned int k = 0; k < numk; k++)
 {
 for (unsigned int j = 0; j < numj; j++)
 {
     for (unsigned int i = 0; i < numi; i++)
     {
         points2->InsertNextPoint(3 + i, j, k);
     }
 }
 }
   structuredGrid2->SetDimensions(numi, numj, numk);
   structuredGrid2->SetPoints(points2);
   structuredGrid2->GetPointData()->SetScalars(dataArray);
   // Create a mapper and actor
   vtkSmartPointer<vtkDataSetMapper> mapper2 =
   vtkSmartPointer<vtkDataSetMapper>::New();
   mapper2->SetInputData(structuredGrid2);
   vtkSmartPointer<vtkActor> actor2 =
   vtkSmartPointer<vtkActor>::New();
   actor2->SetMapper(mapper2);

  // Create a renderer, render window, 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);

  // Add the second renderer for cutter
  vtkSmartPointer<vtkRenderer> renderer2 =
  vtkSmartPointer<vtkRenderer>::New();
  renderWindow->SetSize(800, 400);
  renderWindow->AddRenderer(renderer2);
  renderer->SetViewport(0, 0, 0.5, 1);
  renderer2->SetViewport(0.5, 0, 1, 1);

  vtkSmartPointer<vtkAppendFilter> appendFilter =
  vtkSmartPointer<vtkAppendFilter>::New();
  vtkSmartPointer<vtkCutter> cutter =
  vtkSmartPointer<vtkCutter>::New();
  vtkSmartPointer<vtkPlane> cutPlane =
  vtkSmartPointer<vtkPlane>::New();
  vtkSmartPointer<vtkPolyDataMapper> cutterMapper =
  vtkSmartPointer<vtkPolyDataMapper>::New();
  vtkSmartPointer<vtkActor> cutterActor =
  vtkSmartPointer<vtkActor>::New();

  appendFilter->AddInputData(structuredGrid);
  appendFilter->AddInputData(structuredGrid2);
  cutPlane->SetOrigin(0, 0.5, 0);
  cutPlane->SetNormal(0, 1, 0);
  cutter->SetCutFunction(cutPlane);
  cutter->SetInputConnection(appendFilter->GetOutputPort());
  cutterMapper->SetInputConnection(cutter->GetOutputPort());
  cutterActor->SetMapper(cutterMapper);
  renderer2->AddActor(cutterActor);

  // Add the actor to the scene
  renderer->AddActor(actor);
  renderer->AddActor(actor2);
  renderer->SetBackground(.2, .3, .4);

  // Render and interact
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}
```

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<div class="post-metadata">

### Author: ![Paulo\_Carvalho](https://discourse.vtk.org/user_avatar/discourse.vtk.org/paulo_carvalho/32/370_2.png) [@Paulo\_Carvalho](https://discourse.vtk.org/u/Paulo_Carvalho)
#### Post date: [February 26, 2020, 12:18pm UTC](https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662/3 "2020-02-26T12:18:08Z")

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I think you can report a bug here: [https://gitlab.kitware.com/vtk/vtk/issues](https://gitlab.kitware.com/vtk/vtk/issues)

Please, mention the VTK version (8.9) in the topic title if you decide to file it.

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### Author: ![mwestphal](https://discourse.vtk.org/user_avatar/discourse.vtk.org/mwestphal/32/19_2.png) [@mwestphal](https://discourse.vtk.org/u/mwestphal)
#### Post date: [March 2, 2020, 2:34am UTC](https://discourse.vtk.org/t/vtk8-9-vtkcutter-not-show-scalar-information/2662/4 "2020-03-02T02:34:49Z")

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Already reported and I suggested to post here for more visibility.