Proper handling of View Layers for the VR session was never implemented.
Now the View Layer of the VR session follows the window the session was
started in.
Note that if this window is closed, we fallback to another window. This
is done to avoid the overhead it would take to maintain a separate
depsgraph for the VR view. Instead we always share some already visible
View Layer (and hence the depsgraph).
We want the session to start exactly at the landmark position, with
no additional offset. Some runtimes (e.g. Windows Mixed Reality) may
give an initial non-[0,0,0] position at session start though.
Also add a comment explaining the purpose of the eye offset variable.
There would always be an unintended offset applied. Per design there
should not be any offset when changing VR Landmarks, the view should
just jump exactly to the Landmark.
Due to the recent changes, we don't have to add, but substract the eye
offset we apply to get the wanted behavior.
Mistake in 607d745a79.
Once the base pose was changed (e.g. by changing the active landmark), we'd always run the logic to reset to the base pose. That would mess up the final viewer pose.
Think this only got exposed through 607d745a79.
* Changing to a landmark moves the view exactly to it, rather than
keeping the current position offset.
* Disabling positional tracking moves the viewer back to the landmark
position.
This is a more predictable and practical way to use landmarks. See
feedback in T71347.
On the code side, I did some cleanup so the logic flow is more clear.
Note: This is entirely untested. I currently don't have access to a
device. There might be issues, tomorrow I'll hopefully get feedback.
Draw-manager mutex has to be set before activating OpenGL/GPU context.
Otherwise, parallel jobs (like preview rendering) may try to activate
the context from another thread.
Also: Use WM wrappers for activating/releasing OpenGL context, which
have an additional assert check.
Suggest to backport this for 2.83.1.
The offsets are applied after toggling positional tracking off, so that
the view does not jump at that moment. But when changing the base pose,
keeping that offset doesn't make sense. Especially with landmarks, which
are supposed to give precise positions/rotations to jump to. For that
part the VR Scene Inspection Add-on will need a little adjustment
though.
Also exposes an explicit function to the Python API to reset the
offsets, to be used by the Add-on.
This is mostly untested since I don't have access to an HMD currently.
Splits up wm_xr.c into multiple files in their own folder:
source/blender/windowmanager/xr. So this matches how the message bus and
gizmo code have their own folder and files.
This allows better structuring and should make the code scale better.
I rather do this early on than to wait until we end up with a single,
huge file.
Also improves a bit how data is prepared and updated for drawing.
