I asked CoPilot your question. I hope there are some good ideas for solve your problem:
In Babylon.js, ensuring that the positive Z-axis aligns with the north direction on your map involves a few considerations. Let’s break it down:
- Coordinate System Orientation:
- By default, Babylon.js uses a left-handed coordinate system with the Y-axis pointing up. This means that the positive Z-axis points forward.
- However, you’re working with data that follows a right-handed Z-up coordinate system (commonly used in geospatial applications).
- To achieve alignment, you’ll need to adjust your Babylon.js scene accordingly.
- Camera Position and Target:
- When using the right-handed Z-up system, ensure that your camera’s position and target are provided in Y-up coordinates.
- Set the camera’s upVector to
(0, 0, 1)to maintain the correct orientation.
- Mesh Position Coordinates:
- Babylon.js handles mesh position coordinates in Z-up even when using the right-handed system.
- So, when creating your road, make sure the mesh positions are specified in Z-up coordinates.
- Consistency and Transformations:
- Consistency is key. If your data is in Z-up, consider transforming all input and output vectors and models into the correct coordinate system.
- Alternatively, you can use
scene.useRightHandedSystem, but remember that Babylon.js still operates in a Y-up system (with right-handed mode).
- Mesh Rotation:
- To rotate your road to align with the north direction, you can use
Mesh.lookAt(clickPoint)whereclickPointrepresents the north direction. - This function will adjust your model’s rotation on all three axes to face the specified point.
- Degrees of Rotation:
- The exact number of degrees you need to rotate depends on your specific use case and the deviation you’ve observed.
- Experiment with different angles until your road aligns correctly with the map.
Remember that Babylon.js primarily operates in a left-handed Y-up system, so you might encounter some inconsistencies when working with a right-handed Z-up system.
If possible, consider exporting or re-exporting your scene in a Y-up orientation to avoid constant adjustments12.