Blender Git Loki

XR Controller Support Step 3: XR Events

Integrates XR input actions with the WM event system. With this commit,
all VR action functionality (operator execution, pose querying, haptic
application), with the exception of custom drawing, is enabled.

By itself, this does not bring about any changes for regular users,
however it is necessary for the upcoming VR add-on update that will
expose default controller actions to users.

For add-on developers, this updates the Python API with access to XR
event data (input states, controller poses, etc.), which can be
obtained via the "xr" property added to the bpy.types.Event struct.
For XR events, this property will be non-null and the event will have
the type XR_ACTION.

Further details:
XR-type window events are queued to the regular window queues after
updating and interpreting VR action states. An appropriate window is
found by either using the window the VR session was started in or a
fallback option.

When handling XR events, mouse-specific processing is skipped and
instead a dedicated XR offscreen area and region (see 08511b1c3de0) is
used to execute XR event operators in the proper context.

Reviewed By: Severin

Differential Revision: https://developer.blender.org/D10944