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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>Hello,</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>In trying to generate stream lines over a vector field (surface water velocity vectors) I do not get any output.<SPAN style="mso-spacerun: yes"> </SPAN>My data is a triangle mesh with point attributes containing vectors which are essentially 2d but have all 3 components – only all z-components are 0.</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>I am trying to follow the officetubes.tcl example.<SPAN style="mso-spacerun: yes"> </SPAN>My bounds, length, and time are as follows:</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman">Polydata set length = 141421<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>maxTime = 528908.630328<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>bounds = 440000 540000 3.25e+006 3.35e+006 -56.739 8.841<o:p></o:p></FONT></FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>I set a point at : xst,yst,zst = <SPAN style="mso-spacerun: yes"> </SPAN>490000.0, 3300000.0, -23.949<SPAN style="mso-spacerun: yes"> </SPAN>( in the middle of the dataset).</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>My code is as follows:</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman">vtkRungeKutta4 integ<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman">vtkStreamLine streamer<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetInput [assignVec GetPolyDataOutput]<SPAN style="mso-spacerun: yes"> </SPAN><o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetStartPosition<SPAN style="mso-spacerun: yes"> </SPAN>$xst $yst $zst<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN><SPAN style="mso-spacerun: yes"> </SPAN><o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetMaximumPropagationTime 1000<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetStepLength 10<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetIntegrationStepLength 0.1<o:p></o:p></FONT></FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetIntegrationDirectionToIntegrateBothDirections<o:p></o:p></FONT></FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT size=3><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes"> </SPAN>streamer SetIntegrator integ<o:p></o:p></FONT></FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>Then I use the vtkTubeFilter to get the output of streamer and eventually render.</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>I use “vtkAssignAttribute assignVec” to set the point vectors attribute because the polydata set has over 100 arrays of velocity vectors.</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>Am I at least going in the right direction ?</FONT></P>
<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>Appreciate your help,</FONT></P>
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<P class=MsoNormal style="MARGIN: 0in 0in 0pt"><FONT face="Times New Roman" size=3>Jay </FONT></P></DIV><p><font face=arial size=-1>Do you Yahoo!?<br>
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