Hi all:<br><br>I have a question about drawing a line. <br>Actually, I want to draw a line in display window. But when I change these two points, the line doesn&#39;t looks correct.<br>I follow the example :<br><br><pre class="de1">
<font style="font-family: arial,helvetica,sans-serif;" size="2"><span class="co1">//create two points, P0 and P1</span><br>  <span class="kw4">double</span> p0<span class="br0">[</span><span class="nu0">3</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu16">1.0</span>, <span class="nu16">0.0</span>, <span class="nu16">0.0</span><span class="br0">}</span><span class="sy4">;</span><br>
  <span class="kw4">double</span> p1<span class="br0">[</span><span class="nu0">3</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu16">0.0</span>, <span class="nu16">1.0</span>, <span class="nu16">0.0</span><span class="br0">}</span><span class="sy4">;</span><br>
 <br>  vtkSmartPointer<span class="sy1">&lt;</span>vtkLineSource<span class="sy1">&gt;</span> lineSource <span class="sy1">=</span> <br>      vtkSmartPointer<span class="sy1">&lt;</span>vtkLineSource<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  lineSource<span class="sy2">-</span><span class="sy1">&gt;</span>SetPoint1<span class="br0">(</span>p0<span class="br0">)</span><span class="sy4">;</span><br>  lineSource<span class="sy2">-</span><span class="sy1">&gt;</span>SetPoint2<span class="br0">(</span>p1<span class="br0">)</span><span class="sy4">;</span><br>
  lineSource<span class="sy2">-</span><span class="sy1">&gt;</span>Update<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br> <br>  <span class="co1">//Create a mapper and actor</span><br>  vtkSmartPointer<span class="sy1">&lt;</span>vtkPolyDataMapper<span class="sy1">&gt;</span> mapper <span class="sy1">=</span> <br>
      vtkSmartPointer<span class="sy1">&lt;</span>vtkPolyDataMapper<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  mapper<span class="sy2">-</span><span class="sy1">&gt;</span>SetInputConnection<span class="br0">(</span>lineSource<span class="sy2">-</span><span class="sy1">&gt;</span>GetOutputPort<span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span><br>
  vtkSmartPointer<span class="sy1">&lt;</span>vtkActor<span class="sy1">&gt;</span> actor <span class="sy1">=</span> <br>      vtkSmartPointer<span class="sy1">&lt;</span>vtkActor<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  actor<span class="sy2">-</span><span class="sy1">&gt;</span>SetMapper<span class="br0">(</span>mapper<span class="br0">)</span><span class="sy4">;</span><br> <br>  <span class="co1">//Create a renderer, render window, and interactor</span><br>
  vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderer<span class="sy1">&gt;</span> renderer <span class="sy1">=</span> <br>      vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderer<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderWindow<span class="sy1">&gt;</span> renderWindow <span class="sy1">=</span> <br>      vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderWindow<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  renderWindow<span class="sy2">-</span><span class="sy1">&gt;</span>AddRenderer<span class="br0">(</span>renderer<span class="br0">)</span><span class="sy4">;</span><br>  vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderWindowInteractor<span class="sy1">&gt;</span> renderWindowInteractor <span class="sy1">=</span> <br>
      vtkSmartPointer<span class="sy1">&lt;</span>vtkRenderWindowInteractor<span class="sy1">&gt;</span><span class="sy4">::</span><span class="kw3">New</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  renderWindowInteractor<span class="sy2">-</span><span class="sy1">&gt;</span>SetRenderWindow<span class="br0">(</span>renderWindow<span class="br0">)</span><span class="sy4">;</span><br> <br>  <span class="co1">//Add the actor to the scene</span><br>
  renderer<span class="sy2">-</span><span class="sy1">&gt;</span>AddActor<span class="br0">(</span>actor<span class="br0">)</span><span class="sy4">;</span><br> <br>  <span class="co1">//Render and interact</span><br>  renderWindow<span class="sy2">-</span><span class="sy1">&gt;</span>Render<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span><br>
  renderWindowInteractor<span class="sy2">-</span><span class="sy1">&gt;</span>Start<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></font><br><br><font style="font-family: times new roman,serif;" size="2"><b>But, when I change these two points as</b></font><br>
<br><font><font style="font-family: arial,helvetica,sans-serif;" size="2"><span class="kw4">double</span> p0<span class="br0">[</span><span class="nu0">3</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu16">10.0</span>, <span class="nu16">0.0</span>, <span class="nu16">0.0</span><span class="br0">}</span><span class="sy4">;</span><br>
  <span class="kw4">double</span> p1<span class="br0">[</span><span class="nu0">3</span><span class="br0">]</span> <span class="sy1">=</span> <span class="br0">{</span><span class="nu16">0.0</span>, <span class="nu16">10.0</span>, <span class="nu16">0.0</span><span class="br0">}</span><span class="sy4">;</span></font></font><br>
<br><font style="font-family: times new roman,serif;" size="2">The line doesn&#39;t change. <br><br>Could Anyone tell me what&#39;s the problem?<br>I want to draw a line in display coordinate.<br><br>Thanks<br>Best<br>Erkang</font><br>
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