Questions about world space

[KunpengSong]

Dear Authors,

Thanks for sharing this great work!
I have a few questions about the released dataset:

1. Is the vertical axis of the world space always perpendicular to the ground? (it seems no)
2. or is there a way to calculate the orientation of the camera with respect to the ground of the scene using the released dataset?

Thank you for your time and attention!
Best regards

[YuDeng]

Hi, our world space is defined as the camera space of the first frame used for SLAM. Therefore, it is not guaranteed to be perpendicular to the ground. Some off-the-shelf methods could potentially be used to estimate the gravity direction, such as PerspectiveFields. However, we have not tested their reliability in our specific setting.