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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> I want to volume render a set of
3D points and when I create vtkStructuredPoints to represent the data, I have a
problem where the points seem to be clipped occasionally. To create the
structured points I do the following ...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>m_output =
vtkStructuredPoints::New();<BR> float
bounds[6];<BR> m_source->GetBounds(bounds);<BR> int
x1,x2,y1,y2,z1,z2;<BR> x1 = (int)(floor(bounds[0]));<BR> x2 =
(int)(ceil(bounds[1]));<BR> y1 = (int)(floor(bounds[2]));<BR> y2 =
(int)(ceil(bounds[3]));<BR> z1 = (int)(floor(bounds[4]));<BR> z2 =
(int)(ceil(bounds[5]));</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2> m_iVal = (x2 - x1 + 1);<BR> m_jVal = (y2
- y1 + 1);<BR> m_kVal = (z2 - z1 + 1);</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2> m_output->SetDimensions(m_iVal *
m_xResolution, m_jVal * m_yResolution, m_kVal *
m_zResolution);<BR> m_output->SetSpacing((1.0 / m_xResolution) ,(1.0 /
m_yResolution) ,(1.0 / m_zResolution));
<BR> m_output->SetOrigin(x1,y1,z1);<BR> m_output->SetScalarTypeToUnsignedShort();<BR> m_output->Update();</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>where m_*Resolution *=x,y,z are parameters that
specify the resolution of the structured points in each dimension. Is this the
correct way to used structured points? Most of the time this displays the
correct size volume, but some of the time on large structures it seems to clip
the volume in some dimensions. I am using a vtkVolumeTextureMapper2D to render
the volume, and was wondering if there was a maximum size for the structured
points or if the clipping is a feature that can be controlled in volume
rendering?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>thanks in advance</FONT></DIV>
<DIV><FONT face=Arial size=2>regards Ross</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>
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<CENTER><A style="FONT-SIZE: 150%; COLOR: blue"
href="http://www.acfr.usyd.edu.au/people/postgrads/rhennessy">Ross
Hennessy </A></CENTER></TD></TR>
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<TD>
<DIV><A href="http://www.acfr.usyd.edu.au">Australian Centre for Field
Robotics</A><BR>Rose Street Building, J04<BR><A
href="http://www.usyd.edu.au">University of Sydney</A>, </DIV>
<DIV>NSW 2006, Australia<BR></DIV></TD></TR>
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<TD>Phone:</TD>
<TD>+61 2 9351 3040 </TD></TR>
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<TD>Fax:</TD>
<TD>+61 2 9351 7474
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