Operating system: Linux-4.15.0-46-generic-x86_64-with-debian-buster-sid 64 Bits
Graphics card: GeForce GTX 960M/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 390.116
- 2.80 (sub 51), branch: blender2.7, commit date: 2019-03-21 23:13, hash: rB1ae6aaad43ad
- similar behavior on 2.79
Short description of error
Left-right rotation of camera in "Fly navigation" is inverted when camera is upside down and "upright Z axis" is off. This effect can be seen even if camera is slightly upside down (for example if you look in X-axis direction and rotate around Y-axis more than 90 degrees). Changing "upright Z axis" to ON fixes this issue even if camera is still upside down. Changing it back to OFF produces problem again. If "upright Z axis" is kept ON all the time, you can rotate camera UP to bring it upside down to see that problem only happens when "upright Z axis" is off.
I believe this is bug, because it is counterintuitive and different from behavior in same situation when "upright Z axis" is ON.
Exact steps for others to reproduce the error (blender 2.8, default shortcuts)
- Open any blender scene.
- Press F3 to open search dialog.
- Search "Fly Navigation" and press Enter.
- Press Z to turn off "Upright Z axis".
- Rotate camera upside down (for example move cursor above rectangle in center of screen until camera is upside down).
- Place cursor left of rectangle in center of screen. Camera should rotate left, but it rotates right. Alternatively, place cursor right of rectangle in center of screen.