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<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2>Hi all,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2>I use vtkFixedPointVolumeRayCastMapper for volume
rendering. The image quality is perfect, but I have to wait about 30 sec
for the first rendered image, mainly due </FONT></SPAN><SPAN
class=429432814-31072007><FONT face=Arial color=#000080 size=2>gradient
computation.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2>Currently (VTK-5.0.3) the gradient computation is
implemented in a single thread. I would expect that on </FONT></SPAN><SPAN
class=429432814-31072007><FONT face=Arial color=#000080 size=2>multi-core/CPU
systems the gradient computation could be made 2-4 times faster with a
multi-threaded implementation. </FONT></SPAN><SPAN
class=429432814-31072007><FONT face=Arial color=#000080 size=2>Looking at the
code I've found that the </FONT></SPAN><SPAN
class=429432814-31072007><FONT face=Arial color=#000080 size=2>algorithm in
<SPAN class=429432814-31072007><FONT face=Arial color=#000080
size=2>vtkFixedPointVolumeRayCastMapperComputeGradients </FONT></SPAN>is already
prepared for a multi-threaded implementation.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2>Does anyone know why the multi-threaded gradient
computation just prepared, and finally not implemented for
vtkFixedPointVolumeRayCastMapper?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2>Andras</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429432814-31072007><FONT face=Arial
color=#000080 size=2></FONT></SPAN> </DIV></BODY></HTML>