Question for coordinate system

[SCUTykLin]

Hello:
I appreciate the solid work you've contributed and I‘m very interested in it.
But I have some question for the output(angles). I am trying to correlate the output of "Orient Anything" with some existing coordinate systems(OpenGL, blender, OpenCV...), but I have encountered some issues in this process.

1. code of camera location:

   Orient-Anything/utils.py

   Line 250 in 23c966d

   camera_location = [-1*radius * math.cos(phi), -1*radius * math.tan(theta), radius * math.sin(phi)]

   Is the output angle in spherical coordinates? However, the calculation method for spherical coordinates is as follows: $(r \sin \theta \cos \phi, r \sin \theta \sin \phi, r \cos \theta)$.
2. What is the world coordinate in this project? because I want the transfer the angles which output via Orient Anything to xyz basis in another coordinate systems(OpenGL). View matrix:

   Orient-Anything/render/core.py

   Line 212 in 23c966d

   def look_at(eye: Vec3d, target: Vec3d, up: Vec3d = Vec3d(0, -1, 0)) -> Mat4d:

   Sound like up vector is [0, 1, 0]?

Sorry for bother u.

[SCUTykLin]

To determine the world coordinate system, I employed a somewhat manual and time-consuming method in Blender. Specifically, I placed 16 cameras in the scene and used the rotation of an object to judge the orientation of each camera.

And I think the world coordinate is：The front of the object is aligned with the negative X-axis, object faces in the negative X direction; The right side of the object is aligned with the positive Z-axis, the up of the object is aligned with the positive Y-axis.

I'm not sure if it's correct, but it looks reasonable visually.

[zhang-ziang]

Sorry for some confusing signs issues in the rendering code.
The rendering pipeline in the repo is only for rendering the axis to show visualization results. It is based on render-py, and as the author mentioned in annotation, the model exported by blender has a confusion of coordinate system in render-py. We adjusted some signs to align the coordinate system between the script and blender.
The rendering of the training and test sets is based on the objaverse-xl script, which calls blender directly to render, so there are no coordinate system issues. The front of the object is aligned with the positive X-axis; The right side of the object is aligned with the negative Y-axis, the up of the object is aligned with the positive Z-axis.

[SCUTykLin]

Thanks for your reply, I check my model again

[wanglaofei]

Thank you very much for your excellent work. As a beginner in this field, I would like to ask for your guidance:
Could you kindly explain whether it is feasible to calculate parameters such as pitch, yaw and vertical field of view (vfov) based on the angles or metrics mentioned in your system? If so, could you provide some insights or methodologies for deriving these parameters?
Thank you for your time and support!

[zhang-ziang]

Thank you very much for your excellent work. As a beginner in this field, I would like to ask for your guidance: Could you kindly explain whether it is feasible to calculate parameters such as pitch, yaw and vertical field of view (vfov) based on the angles or metrics mentioned in your system? If so, could you provide some insights or methodologies for deriving these parameters? Thank you for your time and support!

In fact, this is one of the common definitions of Euler angles.
Reference: https://en.wikipedia.org/wiki/Euler_angles