# FilledContours

VTKExamples/CSharp/VisualizationAlgorithms/FilledContours

### Description

This example produces filled contours using the vtkClipPolyData filter. There is a sample data file here

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

FilledContours.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 {
                FilledContours(@"c:\vtk\vtkdata-5.8.0\Data\filledContours.vtp", 10);
             }
             catch(Exception ex) {
                MessageBox.Show(ex.Message, "Exception", MessageBoxButtons.OK);
             }
          }

          private void FilledContours(string filePath, int numberOfContours) {
             // Read the file
             vtkXMLPolyDataReader reader = vtkXMLPolyDataReader.New();

             reader.SetFileName(filePath);
             reader.Update(); // Update so that we can get the scalar range

             double[] scalarRange = reader.GetOutput().GetPointData().GetScalars().GetRange();

             vtkAppendPolyData appendFilledContours = vtkAppendPolyData.New();

             double delta = ( scalarRange[1] - scalarRange[0] ) / ( numberOfContours - 1 );

             // Keep the clippers alive
             List<vtkClipPolyData>  clippersLo = new List<vtkClipPolyData>();
             List<vtkClipPolyData>  clippersHi = new List<vtkClipPolyData>();

             for(int i = 0; i < numberOfContours; i++) {
                double valueLo = scalarRange[0] + i * delta;
                double valueHi = scalarRange[0] + ( i + 1 ) * delta;

                clippersLo.Add(vtkClipPolyData.New());
                clippersLo[i].SetValue(valueLo);
                if(i == 0) {
                   clippersLo[i].SetInputConnection(reader.GetOutputPort());
                }
                else {
                   clippersLo[i].SetInputConnection(clippersHi[i - 1].GetOutputPort(1));
                }
                clippersLo[i].InsideOutOff();
                clippersLo[i].Update();

                clippersHi.Add(vtkClipPolyData.New());
                clippersHi[i].SetValue(valueHi);
                clippersHi[i].SetInputConnection(clippersLo[i].GetOutputPort());
                clippersHi[i].GenerateClippedOutputOn();
                clippersHi[i].InsideOutOn();
                clippersHi[i].Update();
                if(clippersHi[i].GetOutput().GetNumberOfCells() == 0) {
                   continue;
                }

                vtkFloatArray cd = vtkFloatArray.New();
                cd.SetNumberOfComponents(1);
                cd.SetNumberOfTuples(clippersHi[i].GetOutput().GetNumberOfCells());
                cd.FillComponent(0, valueLo);

                clippersHi[i].GetOutput().GetCellData().SetScalars(cd);
                appendFilledContours.AddInputConnection(clippersHi[i].GetOutputPort());
             }

             vtkCleanPolyData filledContours = vtkCleanPolyData.New();
             filledContours.SetInputConnection(appendFilledContours.GetOutputPort());

             vtkLookupTable lut = vtkLookupTable.New();
             lut.SetNumberOfTableValues(numberOfContours + 1);
             lut.Build();
             vtkPolyDataMapper contourMapper = vtkPolyDataMapper.New();
             contourMapper.SetInputConnection(filledContours.GetOutputPort());
             contourMapper.SetScalarRange(scalarRange[0], scalarRange[1]);
             contourMapper.SetScalarModeToUseCellData();
             contourMapper.SetLookupTable(lut);

             vtkActor contourActor = vtkActor.New();
             contourActor.SetMapper(contourMapper);
             contourActor.GetProperty().SetInterpolationToFlat();

             vtkContourFilter contours = vtkContourFilter.New();
             contours.SetInputConnection(filledContours.GetOutputPort());
             contours.GenerateValues(numberOfContours, scalarRange[0], scalarRange[1]);

             vtkPolyDataMapper contourLineMapperer = vtkPolyDataMapper.New();
             contourLineMapperer.SetInputConnection(contours.GetOutputPort());
             contourLineMapperer.SetScalarRange(scalarRange[0], scalarRange[1]);
             contourLineMapperer.ScalarVisibilityOff();

             vtkActor contourLineActor = vtkActor.New();
             contourLineActor.SetMapper(contourLineMapperer);
             contourLineActor.GetProperty().SetLineWidth(2);

             // get a reference to the renderwindow of our renderWindowControl1
             vtkRenderWindow renderWindow = renderWindowControl1.RenderWindow;
             // renderer
             vtkRenderer renderer = renderWindow.GetRenderers().GetFirstRenderer();
             // set background color
             renderer.SetBackground(.2, .3, .4);
             // add our actor to the renderer
             renderer.AddActor(contourActor);
             renderer.AddActor(contourLineActor);
          }
       }
    }