# WritePNG

VTKExamples/CSharp/IO/WritePNG

### 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

### Code

WritePNG.cs

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

    using Kitware.VTK;

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

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

          private void WritePNG() {
             // Path to vtk data must be set as an environment variable
             // VTK_DATA_ROOT = "C:\VTK\vtkdata-5.8.0"
             vtkTesting test = vtkTesting.New();
             string root = test.GetDataRoot();
             string filePath = System.IO.Path.Combine(root, @"Data\test_png.png");
             int[] extent = new int[] { 0, 99, 0, 99, 0, 0 };
             vtkImageCanvasSource2D imageSource = vtkImageCanvasSource2D.New();
             imageSource.SetExtent(extent[0], extent[1], extent[2], extent[3], extent[4], extent[5]);
             imageSource.SetScalarTypeToUnsignedChar();
             imageSource.SetNumberOfScalarComponents(3);
             imageSource.SetDrawColor(127, 45, 255);
             imageSource.FillBox(0, 99, 0, 99);
             imageSource.SetDrawColor(255, 255, 255);
             imageSource.FillBox(40, 70, 20, 50);
             imageSource.Update();

             vtkImageCast castFilter = vtkImageCast.New();
             castFilter.SetOutputScalarTypeToUnsignedChar();
             castFilter.SetInputConnection(imageSource.GetOutputPort());
             castFilter.Update();

             vtkPNGWriter writer = vtkPNGWriter.New();
             writer.SetFileName(filePath);
             writer.SetInputConnection(castFilter.GetOutputPort());
             writer.Write();
             // Read and display file for verification that it was written correctly
             vtkPNGReader reader = vtkPNGReader.New();
             if(reader.CanReadFile(filePath) == 0) {
                MessageBox.Show("Cannot read file \"" + filePath + "\"", "Error", MessageBoxButtons.OK);
                return;
             }
             reader.SetFileName(filePath);
             reader.Update();

             // Visualize
             vtkImageViewer2 imageViewer = vtkImageViewer2.New();
             imageViewer.SetInputConnection(reader.GetOutputPort());
             // get a reference to the renderwindow of our renderWindowControl1
             vtkRenderWindow renderWindow = renderWindowControl1.RenderWindow;
             // renderer
             vtkRenderer renderer = renderWindow.GetRenderers().GetFirstRenderer();
             // set background color
             renderer.SetBackground(0.2, 0.3, 0.4);
             imageViewer.SetRenderer(renderer);
             renderer.ResetCamera();
          }
       }
    }