[vtkusers] World Units

[Wheeler, Gavin]

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.

Gavin Wheeler

From: vtkusers <vtkusers-bounces at public.kitware.com> On Behalf Of Ken Martin
Sent: 19 November 2018 16:22
To: Dave Demarle <dave.demarle at kitware.com>
Cc: vtkusers at public.kitware.com
Subject: Re: [vtkusers] World Units

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.


On Mon, Nov 19, 2018 at 9:57 AM David E DeMarle <dave.demarle at kitware.com<mailto:dave.demarle at kitware.com>> wrote:
vtk itself is unitless. it is up to the application to keep track of that.

David E DeMarle
Kitware, Inc.
Principal Engineer
21 Corporate Drive
Clifton Park, NY 12065-8662
Phone: 518-881-4909


On Mon, Nov 19, 2018 at 9:53 AM Matthew Troke <matthew.troke at avalonholographics.com<mailto:matthew.troke at avalonholographics.com>> wrote:
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.

Matt

--
Matthew Troke
Software Engineer
[http://www.avalonholographics.com/img/logo.png]
Office: 1-709-701-0239
Email: matthew.troke at avalonholographics.com<mailto:matthew.troke at avalonholographics.com>

This email and any attachments are confidential and may be privileged. Any unauthorized use, disclosure, copying or distribution of the information received is prohibited. If you are not the intended recipient please contact the sender immediately by return email confirming that you have and will delete all communications related to the email and any attachments sent to you in error.
_______________________________________________
Powered by www.kitware.com<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.kitware.com&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=e9ywuNm8dLcueQG3C10nNDR6ZYLnRB3kbqf15Nh2%2FWE%3D&reserved=0>

Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.kitware.com%2Fopensource%2Fopensource.html&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=xDG5I%2BfQRBL8wr7LVpQBVE5UMH4cFKrpNzSGE2gMBn0%3D&reserved=0>

Please keep messages on-topic and check the VTK FAQ at: http://www.vtk.org/Wiki/VTK_FAQ<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.vtk.org%2FWiki%2FVTK_FAQ&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=JbRMfZ6pfuh89WuWjNawR1t3MJewwLGFrjI%2B6eOJmAc%3D&reserved=0>

Search the list archives at: http://markmail.org/search/?q=vtkusers<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmarkmail.org%2Fsearch%2F%3Fq%3Dvtkusers&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=1j4tqG4ScbBzSbCHg3hQXjn6FoSvkyrUTR3%2BFGqOpj8%3D&reserved=0>

Follow this link to subscribe/unsubscribe:
https://public.kitware.com/mailman/listinfo/vtkusers<https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpublic.kitware.com%2Fmailman%2Flistinfo%2Fvtkusers&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=1T%2F1LO6cF5VnjPoq0w8gEYt%2Fu9Gk%2BCtMXWPXFQApgco%3D&reserved=0>
_______________________________________________
Powered by www.kitware.com<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.kitware.com&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=e9ywuNm8dLcueQG3C10nNDR6ZYLnRB3kbqf15Nh2%2FWE%3D&reserved=0>

Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.kitware.com%2Fopensource%2Fopensource.html&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=xDG5I%2BfQRBL8wr7LVpQBVE5UMH4cFKrpNzSGE2gMBn0%3D&reserved=0>

Please keep messages on-topic and check the VTK FAQ at: http://www.vtk.org/Wiki/VTK_FAQ<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.vtk.org%2FWiki%2FVTK_FAQ&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=JbRMfZ6pfuh89WuWjNawR1t3MJewwLGFrjI%2B6eOJmAc%3D&reserved=0>

Search the list archives at: http://markmail.org/search/?q=vtkusers<https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fmarkmail.org%2Fsearch%2F%3Fq%3Dvtkusers&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=1j4tqG4ScbBzSbCHg3hQXjn6FoSvkyrUTR3%2BFGqOpj8%3D&reserved=0>

Follow this link to subscribe/unsubscribe:
https://public.kitware.com/mailman/listinfo/vtkusers<https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpublic.kitware.com%2Fmailman%2Flistinfo%2Fvtkusers&data=01%7C01%7Cgavin.wheeler%40kcl.ac.uk%7C9f528c04320c4e2ca9e308d64e3b3644%7C8370cf1416f34c16b83c724071654356%7C0&sdata=1T%2F1LO6cF5VnjPoq0w8gEYt%2Fu9Gk%2BCtMXWPXFQApgco%3D&reserved=0>


--
Ken Martin PhD
Distinguished Engineer
Kitware Inc.
101 East Weaver Street
Carrboro, North Carolina
27510 USA
This communication, including all attachments, contains confidential and legally privileged information, and it is intended only for the use of the addressee.  Access to this email by anyone else is unauthorized. If you are not the intended recipient, any disclosure, copying, distribution or any action taken in reliance on it is prohibited and may be unlawful. If you received this communication in error please notify us immediately and destroy the original message.  Thank you.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://public.kitware.com/pipermail/vtkusers/attachments/20181120/5652850c/attachment.html>