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<p class=MsoNormal style='text-autospace:none'><font size=2 color=blue
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:blue'>I derive a class from </span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>vtkVolumeRayCastCompositeFunction
as:<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'>Class VTK_RENDERING_EXPORT
aktVolumeRayCastDRRCompositeFunction :<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> <font color=blue><span
style='color:blue'>public</span></font> vtkVolumeRayCastCompositeFunction<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>The only function I override is the RayCast
function. I create an instance of the new derived class as follows:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>aktVolumeRayCastDRRCompositeFunction
*compositeFunction = (aktVolumeRayCastDRRCompositeFunction *)
aktVolumeRayCastDRRCompositeFunction::New();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>And pass this composite function to the volume mapper.
But the RayCast function that I override does not seem to get called. Instead
the one in vtkVolumeRayCastCompositeFunction is being called. I am obviously
missing something here. Can anyone tell me what should be the steps to
successfully override from vtkVolumeRayCastCompositeFunction. Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>-Cheers,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>Abhishek</span></font> <o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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