Happy new year to the wonderful Godot community!
We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.
Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
A z_depth of 0 returns the camera position, which is not really useful.
This also makes the API breakage from 3.1 clearer as 3.1 code will now
fail to compile, so users will have to adapt and use the new parameter.
For the reference, in 3.1, the z_depth was hardcoded to the near plane.
Closes#33493.
