3

When I export a Collada file from QGIS 2.18.23 using the amazing QGIS2threejs plugin version 1.4.2, my Collada file comes into Blender and Sketchup with the East West mirrored. This is not the case in the browser or when I export an .obj.

I don't know of a way to fix it in Sketchup or Blender because it would require being both flipped and turned insideout. I know I could use Blender to convert the .obj to a .dae but I need my students who will have QGIS and Sketchup installed but not Blender to be able to export and use a Collada file.

The .dae is a of a lidar derived DEM in MA State Plane Feet.

In QGIS 3 the plugin has been updated and .gltf is the only export option.

An alternative conversion process that results in a .dae would be acceptable.

Improve this question
5
  • i think it might be the right hand rule here?
    – Steven Kay
    Commented Sep 28, 2018 at 23:17
  • or possibly a rotation of the order of the axes : xyz / yzx / zxy
    – Steven Kay
    Commented Sep 28, 2018 at 23:49
  • I tried a different CRS in case it was a issue there. No luck. If it helps all of the exports, .dae and .obj come into blender with North down but only the .dae are mirrored. If it is a right hand or coordinate order mix up any thing I can easiliy do on my side?
    – Baswein
    Commented Sep 29, 2018 at 0:33
  • I don't see an option to export to collada from Qgis2ThreeJS (the docs claim there's a webpage template that lets you do this, but I don't see the option in QGIS3/Mac). If you could edit your question to mention how you do this (and which version of QGIS) I'll see if I can reproduce this. Collada files supposedly have an orientation matrix in the .dae file so there should be some way to fix this. Alsowhat are you exporting, is it a DEM-derived mesh or models used for points? If it's a DEM it could be a negative y pixel value
    – Steven Kay
    Commented Sep 29, 2018 at 18:36
  • Thanks Steven. The export option has been removed in the QGIS 3 version. In EPSG 3857 the X coordinate is negative which could result in what I am seeing.
    – Baswein
    Commented Sep 30, 2018 at 1:26

0

Reset to default

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.