Hi again,<br><br>As per my previous problem of mixing 2d and 3d actors in the same scene, I thought it might be a graphics card problem. So, I managed to get another windows machine (I was using Linux before) but I still see the same problem.... the 2d actor only gets displayed when I do a pick operation on the 3d actor.... This is completely bizarre and after several days I have come with no explanation for that. I have stepped through the renderer code multiple times during debug, but see nothing that could offer some kind of explanation.
<br><br>I really wish someone here would take a look at this very trivial code and see if they could point something out. I tried to convert everything in my code to 3d actors but that presents another set of complications, unfortunately.
<br><br>I am attaching the code again. I really request someone to please help me. It will not take too much of your time. The code is really small and functional.<br><br>#include &quot;vtkImageData.h&quot;<br>#include &quot;
vtkImageActor.h&quot;<br>#include &quot;vtkActor2D.h&quot;<br>#include &quot;vtkRenderWindow.h&quot;<br>#include &quot;vtkRenderer.h&quot;<br>#include &quot;vtkRenderWindowInteractor.h&quot;<br>#include &quot;vtkImageMapper.h
&quot;<br>#include &quot;vtkPNGReader.h&quot;<br>#include &quot;vtkImageChangeInformation.h&quot;<br><br>int main ()<br>{<br>&nbsp;&nbsp;&nbsp; // Read the image<br>&nbsp;&nbsp;&nbsp; vtkPNGReader * cursorImage = vtkPNGReader::New();<br>&nbsp;&nbsp;&nbsp; // Please replace with your own path
<br>&nbsp;&nbsp;&nbsp; cursorImage-&gt;SetFileName(&quot;C:\\crosshair.png&quot;);<br>&nbsp;&nbsp;&nbsp; cursorImage-&gt;Update();<br>&nbsp;&nbsp;&nbsp; // Shift center to image data oigin<br>&nbsp;&nbsp;&nbsp; vtkImageChangeInformation * imageChange = vtkImageChangeInformation::New();
<br>&nbsp;&nbsp;&nbsp; imageChange-&gt;SetInput(cursorImage-&gt;GetOutput());<br>&nbsp;&nbsp;&nbsp; imageChange-&gt;CenterImageOn();&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <br><br>&nbsp; &nbsp;&nbsp;&nbsp; // create actor2d<br>&nbsp;&nbsp;&nbsp; vtkImageMapper * mapper = vtkImageMapper::New();<br>&nbsp;&nbsp;&nbsp; mapper-&gt;SetInput(imageChange-&gt;GetOutput());
<br>&nbsp;&nbsp;&nbsp; mapper-&gt;SetColorWindow(256.0);<br>&nbsp;&nbsp;&nbsp; mapper-&gt;SetColorLevel(128.0);<br>&nbsp;&nbsp;&nbsp; vtkActor2D * actor2d = vtkActor2D::New();<br>&nbsp;&nbsp;&nbsp; actor2d-&gt;SetMapper(mapper);<br>&nbsp;&nbsp;&nbsp; actor2d-&gt;SetPosition(120.0, 100.0);<br><br>
&nbsp;&nbsp;&nbsp; // create actor 3d<br>&nbsp;&nbsp;&nbsp; vtkImageActor * actor3d = vtkImageActor::New();<br>&nbsp;&nbsp;&nbsp; actor3d-&gt;SetInput(imageChange-&gt;GetOutput());<br><br>&nbsp;&nbsp;&nbsp; // following lines creates our 2 layers of renderers&nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; vtkRenderer *ren1 = vtkRenderer::New(); // 2d actor&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; 
<br>&nbsp;&nbsp;&nbsp; ren1-&gt;AddViewProp(actor2d);&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; ren1-&gt;SetLayer(0); // bottom layer&nbsp;&nbsp;&nbsp; <br><br>&nbsp;&nbsp;&nbsp; vtkRenderer *ren2 = vtkRenderer::New();<br>&nbsp;&nbsp;&nbsp; ren2-&gt;AddViewProp(actor3d); // 3d actor&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; ren2-&gt;SetLayer(1); // top layer&nbsp;&nbsp;&nbsp; 
<br><br>&nbsp;&nbsp;&nbsp; vtkRenderWindow *renWin = vtkRenderWindow::New();&nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; renWin-&gt;SetNumberOfLayers(2); // we have 2 layers of renderers in our window&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; renWin-&gt;AddRenderer(ren1);<br>&nbsp;&nbsp;&nbsp; renWin-&gt;AddRenderer(ren2);&nbsp; &nbsp;&nbsp;&nbsp; 
<br><br>&nbsp;&nbsp;&nbsp; vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New(); // an interactor<br>&nbsp;&nbsp;&nbsp; iren-&gt;SetRenderWindow(renWin);<br>&nbsp;&nbsp;&nbsp; renWin-&gt;Render();&nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; iren-&gt;Start();<br>&nbsp;&nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp; // We will not bother with deletions...program is ending anyways...
<br>&nbsp;&nbsp;&nbsp; return 0;<br>} <br><br>The crosshair.png image can be downloaded from here...<br><br><a href="http://pligame.sourceforge.net/images/crosshair.png">http://pligame.sourceforge.net/images/crosshair.png</a><br><br>&nbsp;<br>
Cheers,<br><br>Anja