Forum

Author Topic: GLB 3d Model rotated after export  (Read 2384 times)

Giancarlo

  • Newbie
  • *
  • Posts: 5
    • View Profile
GLB 3d Model rotated after export
« on: December 26, 2022, 09:36:06 PM »
Hi, I have a problem exporting a 3d model in .GLB format.
My model is georeferenced (EPSG 6708) and when I try to export it in GLB format, it appears rotated 90 degrees along the X axis.

Every software I use to view the model shows this error. How can I do to export the model correctly? Thank you

FabianN

  • Newbie
  • *
  • Posts: 15
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #1 on: January 13, 2023, 02:10:10 PM »
I also report this bug in another reference frame (EPSG 2056).
Hopefully the Agisoft team will fix it soon.

Thanks.

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 14847
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #2 on: January 13, 2023, 02:34:36 PM »
Hello Giancarlo and Fabian,

Do you use Local Coordinates option in the Export Model dialog or select any geographic/projected system?
Best regards,
Alexey Pasumansky,
Agisoft LLC

FabianN

  • Newbie
  • *
  • Posts: 15
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #3 on: January 17, 2023, 12:33:17 PM »
Hi Alexey,

In my case, it is happening in the geographic/projected CS.


Giancarlo

  • Newbie
  • *
  • Posts: 5
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #4 on: January 30, 2023, 12:07:29 AM »
Hello Giancarlo and Fabian,

Do you use Local Coordinates option in the Export Model dialog or select any geographic/projected system?

Local coordinates

flyingburrito

  • Newbie
  • *
  • Posts: 2
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #5 on: January 08, 2024, 04:41:05 AM »
I'm following up to see if this issue has been resolved.  I too had my model rotated when I exported it as a GLB.  I am using map coordinates (a UTM projection).  The top-down view becomes the front-facing view when exported.

Thanks!

Paco

Added on 1/8/2024:

As a follow-up, this may be related to the coordinate system.  Metashape is exporting the 3D models in a right-handed (E-N-U) coordinate system, like most geospatial software would expect.  The glTF also uses a right-handed system, but relative to the 3d asset -- NOT the global cartesian reference frame.  In this regard, "glTF uses a right-handed coordinate system. glTF defines +Y as up, +Z as forward, and -X as right; the front of a glTF asset faces +Z."  See https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html

For t his reason, the 3D landscape appears rotated toward the viewer about the X-axis by 90 degrees.

This is fine for a small object, but it messes up the orientation of a landscape ingested as a 3D element. 
« Last Edit: January 08, 2024, 09:53:25 PM by flyingburrito »

Alexey Pasumansky

  • Agisoft Technical Support
  • Hero Member
  • *****
  • Posts: 14847
    • View Profile
Re: GLB 3d Model rotated after export
« Reply #6 on: March 21, 2024, 04:45:55 PM »
In Metashape 2.1.1 it is possible to select "use glTF Y-up convention" option in the Export Model dialog when glTF format is used.
Best regards,
Alexey Pasumansky,
Agisoft LLC