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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">We’ve not been using OpenVR directly, but have been using it indirectly with medical data. We ended up using m as the real world units,
and then scaling loaded medical data by a factor of 1000 to convert from the commonly used mm, to m. This has worked well, but there are the odd gotchas when doing this– watch out for things like volume rendering step size which you may also need to scale.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US">Gavin Wheeler<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> vtkusers <vtkusers-bounces@public.kitware.com>
<b>On Behalf Of </b>Ken Martin<br>
<b>Sent:</b> 19 November 2018 16:22<br>
<b>To:</b> Dave Demarle <dave.demarle@kitware.com><br>
<b>Cc:</b> vtkusers@public.kitware.com<br>
<b>Subject:</b> Re: [vtkusers] World Units<o:p></o:p></span></p>
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<p class="MsoNormal">Although the OpenVR module does use the notion of a physical to world transformation to map between meters in the VR room and the world coordinates.<o:p></o:p></p>
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<p class="MsoNormal">On Mon, Nov 19, 2018 at 9:57 AM David E DeMarle <<a href="mailto:dave.demarle@kitware.com">dave.demarle@kitware.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">vtk itself is unitless. it is up to the application to keep track of that.<o:p></o:p></p>
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<p class="MsoNormal">David E DeMarle<br>
Kitware, Inc.<br>
Principal Engineer<br>
21 Corporate Drive<br>
Clifton Park, NY 12065-8662<br>
Phone: 518-881-4909<o:p></o:p></p>
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<p class="MsoNormal">On Mon, Nov 19, 2018 at 9:53 AM Matthew Troke <<a href="mailto:matthew.troke@avalonholographics.com" target="_blank">matthew.troke@avalonholographics.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">What units are world dimensions in VTK? For example, if I create a cube that is 1.0 in width, is that considered to be 1 meter, 1 cm, etc? Or are they unitless and defined by the source data? I assume if you are loading in some type of
medical data, units are important.<o:p></o:p></p>
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<p class="MsoNormal">Matt<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal"><span style="color:black">Matthew Troke</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="color:black">Software Engineer</span><o:p></o:p></p>
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<p class="MsoNormal"><img border="0" width="200" height="46" style="width:2.0833in;height:.4791in" id="_x0000_i1025" src="http://www.avalonholographics.com/img/logo.png"><o:p></o:p></p>
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<p class="MsoNormal"><span style="color:black">Office: 1-709-701-0239</span><o:p></o:p></p>
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<p class="MsoNormal"><span style="color:black">Email:</span> <a href="mailto:matthew.troke@avalonholographics.com" target="_blank">
matthew.troke@avalonholographics.com</a><o:p></o:p></p>
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<p class="MsoNormal"><span lang="EN-CA"><o:p> </o:p></span></p>
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<p class="MsoNormal">Ken Martin PhD<o:p></o:p></p>
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<p class="MsoNormal">Distinguished Engineer<br>
<span style="font-size:9.5pt">Kitware Inc.</span><o:p></o:p></p>
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