# Planes

VTKExamples/CSharp/GeometricObjects/Planes

### 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

Planes.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 {
                Planes();
             }
             catch(Exception ex) {
                MessageBox.Show(ex.Message, "Exception", MessageBoxButtons.OK);
             }
          }

          private void Planes() {
             // in this example we need the renderer first to retrieve the active camera
             // in order to get camera's frustum planes and renderer's aspectratio
             vtkRenderWindow renderWindow = renderWindowControl1.RenderWindow;
             vtkRenderer renderer = vtkRenderer.New();
             renderer = renderWindow.GetRenderers().GetFirstRenderer();
             vtkCamera camera = renderer.GetActiveCamera();
             double[] aspect = renderer.GetAspect();
             double aspectRatio = aspect[0] / aspect[1];

             vtkPlanes planes = vtkPlanes.New();
             // one way
             {
                // allocate memory for 24 unmanaged doubles
                int size = Marshal.SizeOf(typeof(double)) * 24;
                IntPtr ptr = Marshal.AllocHGlobal(size);
                camera.GetFrustumPlanes(aspectRatio, ptr);
                // in case we would need this values diectly we could copy
                // the unmanaged double array to a managed array like so:

                // double[] planesArray = new double[24];
                // Marshal.Copy(ptr, planesArray, 0, 24);

                // but fortunately we can forward the IntPtr directly to the function
                // SetFrustumPlanes()
                planes.SetFrustumPlanes(ptr);
                // free unmanaged memory
                Marshal.FreeHGlobal(ptr);
             }
             // another way
             {
                vtkSphereSource sphereSource = vtkSphereSource.New();
                sphereSource.Update();
                double[] bounds = new double[6];
                bounds = sphereSource.GetOutput().GetBounds();
                planes.SetBounds(bounds[0], bounds[1], bounds[2], bounds[3], bounds[4], bounds[5]);
             }
             // nothing to visualize
          }
       }
    }