Hi Jerry,<br /><br />
in this example I draw for demonstration purposes a grid of lines into the scene.<br /><br />
Note: This example has been written just to demonstrate mixing VTK with OpenGL is working, but it has to be extended in many aspects.<br />
Resizing is not handled properly. Perspective projection isn't tested.<br />
Anyhow I hope it's a good starting point.<br />
<pre><span style=' color: Blue;'>using</span> System;
<span style=' color: Blue;'>using</span> System.ComponentModel;
<span style=' color: Blue;'>using</span> System.Windows.Forms;
<span style=' color: Blue;'>using</span> System.Diagnostics;
<span style=' color: Blue;'>using</span> Kitware.VTK;
<span style=' color: Blue;'>using</span> SharpGL;
<span style=' color: Blue;'>using</span> SharpGL.Enumerations;
<span style=' color: Blue;'>namespace</span> TestActiViz {
<span style=' color: Blue;'>public</span> <span style=' color: Blue;'>partial</span> <span style=' color: Blue;'>class</span> Form1 : Form {
<span style=' color: Blue;'>protected</span> OpenGL _GL;
<span style=' color: Blue;'>protected</span> RenderContextType _RenderContextType;
vtkRenderWindow _RenderWindow;
vtkRenderer _Renderer;
IntPtr _Context;
<span style=' color: Blue;'>bool</span> _IsOpenGLInitialized = <span style=' color: Maroon;'>false</span>;
<span style=' color: Blue;'>public</span> Form1() {
InitializeComponent();
_GL = <span style=' color: Blue;'>new</span> OpenGL();
_RenderContextType = RenderContextType.NativeWindow;
}
<span style=' color: Blue;'>private</span> <span style=' color: Blue;'>bool</span> InitOpenGL() {
<span style=' color: Blue;'>if</span>(!_IsOpenGLInitialized) {
vtkWin32OpenGLRenderWindow rw1 = vtkWin32OpenGLRenderWindow.SafeDownCast(_RenderWindow);
_Context = rw1.GetGenericContext();
IntPtr windowId = rw1.GetGenericWindowId();
<span style=' color: Blue;'>int</span>[] size = _RenderWindow.GetSize();
<span style=' color: Blue;'>int</span> bitdepth = _RenderWindow.GetDepthBufferSize();
Debug.WriteLine(<span style=' color: Maroon;'>"Bit depth: "</span> + _RenderWindow.GetDepthBufferSize());
<span style=' color: Blue;'>bool</span> ret = _GL.Create(_RenderContextType, size[<span style=' color: Maroon;'>0</span>], size[<span style=' color: Maroon;'>1</span>], bitdepth, windowId);
<span style=' color: Blue;'>if</span>(ret) {
_IsOpenGLInitialized = <span style=' color: Maroon;'>true</span>;
}
<span style=' color: Blue;'>return</span> ret;
}
<span style=' color: Blue;'>return</span> <span style=' color: Maroon;'>true</span>;
}
<span style=' color: Blue;'>private</span> <span style=' color: Blue;'>void</span> renderWindowControl1_Load(<span style=' color: Blue;'>object</span> sender, EventArgs e) {
vtkSphereSource sphere = vtkSphereSource.New();
vtkPolyDataMapper mapper = vtkPolyDataMapper.New();
mapper.SetInputConnection(sphere.GetOutputPort());
<span style=' color: Green;'>// _Actor</span>
vtkActor actor = vtkActor.New();
actor.SetMapper(mapper);
actor.GetProperty().SetColor(<span style=' color: Maroon;'>1</span>, <span style=' color: Maroon;'>0</span>, <span style=' color: Maroon;'>0</span>);
<span style=' color: Green;'>// get a reference to the renderwindow of our renderWindowControl1</span>
_RenderWindow = renderWindowControl1.RenderWindow;
_Renderer = _RenderWindow.GetRenderers().GetFirstRenderer();
_Renderer.EndEvt += <span style=' color: Blue;'>new</span> vtkObject.vtkObjectEventHandler(renderer_EndEvt);
_Renderer.StartEvt += <span style=' color: Blue;'>new</span> vtkObject.vtkObjectEventHandler(renderer_StartEvt);
<span style=' color: Green;'>// set background color</span>
_Renderer.SetBackground(<span style=' color: Maroon;'>0</span><span style=' color: Maroon;'>.2</span>, <span style=' color: Maroon;'>0</span><span style=' color: Maroon;'>.3</span>, <span style=' color: Maroon;'>0</span><span style=' color: Maroon;'>.4</span>);
<span style=' color: Green;'>// add our actor to the _Renderer</span>
_Renderer.AddActor(actor);
}
<span style=' color: Blue;'>void</span> renderer_StartEvt(vtkObject sender, vtkObjectEventArgs e) {
<span style=' color: Blue;'>if</span>(!_IsOpenGLInitialized) {
<span style=' color: Green;'>//Debug.WriteLine("renderer_StartEvt");</span>
<span style=' color: Blue;'>if</span>(InitOpenGL())
_RenderWindow.SwapBuffersOff();
}
}
<span style=' color: Blue;'>void</span> renderer_EndEvt(vtkObject sender, vtkObjectEventArgs e) {
<span style=' color: Blue;'>if</span>(_IsOpenGLInitialized) {
<span style=' color: Green;'>//Debug.WriteLine("renderer_EndEvt");</span>
<span style=' color: Green;'>// next commented line has the same effect as _GL.MakeCurrent()</span>
<span style=' color: Green;'>//renderWindowControl1.RenderWindow.MakeCurrent();</span>
_GL.MakeCurrent();
_GL.MatrixMode(MatrixMode.Projection);
_GL.LoadIdentity();
_GL.Ortho(<span style=' color: Maroon;'>0</span>, renderWindowControl1.Width, renderWindowControl1.Height, <span style=' color: Maroon;'>0</span>, -<span style=' color: Maroon;'>10</span>, <span style=' color: Maroon;'>10</span>);
_GL.Clear(SharpGL.OpenGL.GL_DEPTH_BUFFER_BIT); <span style=' color: Green;'>// really needed ???</span>
<span style=' color: Green;'>// draw our own stuff</span>
Draw2DGrid();
_GL.Flush();
_GL.Blit(_Context);
}
}
<span style=' color: Blue;'>private</span> <span style=' color: Blue;'>void</span> Draw2DGrid() {
<span style=' color: Blue;'>int</span>[] size = _RenderWindow.GetSize();
<span style=' color: Blue;'>int</span> boxSize = <span style=' color: Maroon;'>10</span>;
<span style=' color: Blue;'>float</span> z = <span style=' color: Maroon;'>0</span><span style=' color: Maroon;'>.0f</span>;
<span style=' color: Blue;'>int</span> n = size[<span style=' color: Maroon;'>0</span>] / boxSize;
<span style=' color: Blue;'>int</span> m = size[<span style=' color: Maroon;'>1</span>] / boxSize;
_GL.LineWidth(<span style=' color: Maroon;'>1</span><span style=' color: Maroon;'>.0f</span>);
_GL.Begin(SharpGL.Enumerations.BeginMode.Lines);
<span style=' color: Green;'>// vertical grid lines</span>
<span style=' color: Blue;'>for</span>(<span style=' color: Blue;'>int</span> i = <span style=' color: Maroon;'>0</span>; i < n; i++) {
_GL.Vertex(i * boxSize + <span style=' color: Maroon;'>1</span>, <span style=' color: Maroon;'>0</span>, z);
_GL.Vertex(i * boxSize + <span style=' color: Maroon;'>1</span>, size[<span style=' color: Maroon;'>1</span>], z);
}
<span style=' color: Green;'>// horizontal grid lines</span>
<span style=' color: Blue;'>for</span>(<span style=' color: Blue;'>int</span> i = <span style=' color: Maroon;'>0</span>; i < m; i++) {
_GL.Vertex(<span style=' color: Maroon;'>0</span>, i * boxSize, z);
_GL.Vertex(size[<span style=' color: Maroon;'>0</span>], i * boxSize, z);
}
_GL.End();
}
}
}
</pre>
<br />
with kind regards<br />
Jochen
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