# HighlightBadCells

VTKExamples/CSharp/PolyData/HighlightBadCells

### Description

A tutorial on how to setup a Windows Forms Application utilizing ActiViz.NET can be found here: Setup a Windows Forms Application to use ActiViz.NET
Note: As long as ActiViz.NET is not build with VTK version 6.0 or higher you must define the preprocessor directive VTK_MAJOR_VERSION_5.

### Code

HighlightBadCells.cs

    using System;
    using System.Collections.Generic;
    using System.ComponentModel;
    using System.Windows.Forms;
    using System.Diagnostics;

    using Kitware.VTK;

    namespace ActiViz.Examples {
       public partial class Form1 : Form {
          public Form1() {
             InitializeComponent();
          }

          private void renderWindowControl1_Load(object sender, EventArgs e) {
             try {
                HighLightBadCells();
             }
             catch(Exception ex) {
                MessageBox.Show(ex.Message, "Exception", MessageBoxButtons.OK);
             }
          }

          private void HighLightBadCells() {
             vtkSphereSource sphereSource = vtkSphereSource.New();
             sphereSource.Update();

             vtkTriangleFilter triangleFilter = vtkTriangleFilter.New();
             triangleFilter.SetInputConnection(sphereSource.GetOutputPort());
             triangleFilter.Update();

             //Create a mapper and actor
             vtkDataSetMapper sphereMapper = vtkDataSetMapper.New();
             sphereMapper.SetInputConnection(triangleFilter.GetOutputPort());
             vtkActor sphereActor = vtkActor.New();
             sphereActor.SetMapper(sphereMapper);

             vtkPolyData mesh = triangleFilter.GetOutput();
             Debug.WriteLine("There are " + mesh.GetNumberOfCells() + " cells.");

             vtkMeshQuality qualityFilter = vtkMeshQuality.New();
    #if VTK_MAJOR_VERSION_5
             qualityFilter.SetInput(mesh);
    #else
             qualityFilter.SetInputData(mesh);
    #endif
             qualityFilter.SetTriangleQualityMeasureToArea();
             qualityFilter.Update();

             vtkDataSet qualityMesh = qualityFilter.GetOutput();
             vtkDoubleArray qualityArray = vtkDoubleArray.SafeDownCast(qualityMesh.GetCellData().GetArray("Quality"));
             Debug.WriteLine("There are " + qualityArray.GetNumberOfTuples() + " values.");

             for(int i = 0; i < qualityArray.GetNumberOfTuples(); i++) {
                double val = qualityArray.GetValue(i);
                Debug.WriteLine("value " +  i + ": " + val);
             }

             vtkThreshold selectCells = vtkThreshold.New();
             selectCells.ThresholdByLower(.02);
             selectCells.SetInputArrayToProcess(
                0,
                0,
                0,
                1, // POINTS = 0, CELLS = 1, NONE = 2, POINTS_THEN_CELLS = 3, VERTICES = 4, EDGES = 5, ROWS = 6
                0  // SCALARS = 0, VECTORS = 1, NORMALS = 2, TCOORDS = 3, TENSORS = 4, GLOBALIDS = 5, PEDIGREEIDS = 6, EDGEFLAG = 7
                );

    #if VTK_MAJOR_VERSION_5
             selectCells.SetInput(qualityMesh);
    #else
             selectCells.SetInputData(qualityMesh);
    #endif
             selectCells.Update();
             vtkUnstructuredGrid ug = selectCells.GetOutput();

             // Create a mapper and actor
             vtkDataSetMapper mapper = vtkDataSetMapper.New();
    #if VTK_MAJOR_VERSION_5
             mapper.SetInput(ug);
    #else
             mapper.SetInputData(ug);
    #endif
             vtkActor actor = vtkActor.New();
             actor.SetMapper(mapper);
             actor.GetProperty().SetColor(1.0, 0.0, 0.0);
             actor.GetProperty().SetRepresentationToWireframe();
             actor.GetProperty().SetLineWidth(5);
             // get a reference to the renderwindow of our renderWindowControl1
             vtkRenderWindow renderWindow = renderWindowControl1.RenderWindow;
             // renderer
             vtkRenderer renderer = renderWindow.GetRenderers().GetFirstRenderer();
             // set background color
             renderer.SetBackground(1.0, 1.0, 1.0);
             // add our actors to the renderer
             renderer.AddActor(actor);
             renderer.AddActor(sphereActor);
          }
       }
    }