ODM 3D Tiles Incorrect Rotation and Geographic Alignment in CesiumJS

[aladeen-burgers]

Overview

ODM-generated 3D Tiles have incorrect orientation and are not properly geographically aligned when visualized in CesiumJS.

Environment

• ODM: 3.6.2
• CesiumJS: 1.138
• Output: OGC 3D Tiles
• Input: Drone imagery

Issue

When generating 3D Tiles directly with ODM 3.6.2 and loading the resulting tileset.json in CesiumJS 1.138, the 3D model is incorrectly rotated and is not properly aligned with its geographic position.

The reconstructed model itself appears correct in ODM outputs, but the 3D Tiles representation has an incorrect orientation and geographic alignment.

Expected Result

The ODM-generated 3D Tiles should:

• Preserve the correct model orientation.
• Be correctly aligned with the corresponding latitude/longitude location.
• Align with the orthophoto, terrain, and other georeferenced ODM outputs.
• Display correctly in CesiumJS without requiring manual rotation or position correction.

Actual Result

The 3D Tiles:

• Appear rotated relative to the expected geographic orientation.
• Are not correctly aligned geographically with the expected latitude/longitude location.
• Do not properly match the corresponding orthophoto/terrain.
• Require manual transformation/rotation in CesiumJS to visually align the model.

Steps to Reproduce

1. Process drone imagery using ODM 3.6.2.
2. Enable the 3d-tiles output.
3. Complete the ODM reconstruction.
4. Load the generated 3d_tiles/model/tileset.json in CesiumJS 1.138.
5. Compare the model orientation and position against the geographic map/terrain and other georeferenced ODM outputs.

Additional Information

The problem appears to be specific to the generated 3D Tiles transformation/georeferencing. In particular, the root transform matrix in tileset.json may be responsible for the incorrect orientation and/or geographic alignment.

The issue is reproducible with the same workflow and should be investigated in the ODM 3D Tiles generation stage.