Fix the controller vibration API

[m4gr3d]

The vrapi_SetHapticVibrationSimple(...) method is supposed to be called once per frame.
To comply, the new logic batches the vibration requests (last one wins), and fire the method call once per frame during _process if a vibration request for the controller is available.
The API exposed by the plugin is augmented to take a duration_in_ms parameter, which the logic uses to keep firing vrapi_SetHapticVibrationSimple(...) calls until the duration has been reached.

The controller demo has been updated to make the touch controllers vibrate when the A/X button is pressed.

[NeoSpark314]

Later today I will be able to give this a test-run. Just a quick question. How does this new rumble API relate to the godot ARVRController.set_rumble(float) (https://docs.godotengine.org/en/stable/classes/class_arvrcontroller.html)
that is implemented here

godot_oculus_mobile/plugin/src/main/cpp/ovr_mobile_controller.cpp

Line 43 in 88f7894

void OvrMobileController::update_controller_vibration(ovrMobile *ovr, ControllerState& controller_state) {

?

[m4gr3d]

Later today I will be able to give this a test-run. Just a quick question. How does this new rumble API relate to the godot ARVRController.set_rumble(float) (https://docs.godotengine.org/en/stable/classes/class_arvrcontroller.html)
that is implemented here

godot_oculus_mobile/plugin/src/main/cpp/ovr_mobile_controller.cpp

Line 43 in 88f7894

void OvrMobileController::update_controller_vibration(ovrMobile *ovr, ControllerState& controller_state) {

?

It's a superset of that API.
With this PR, there are now two ways to make the controllers vibrate:

• Either the ARVRController.set_rumble(float) is used, in which case same behavior as before.
• Or the OvrInput.vibrate_controller method can be used, in which case the vibration request is batched and executed in the next frame (unless a new request overrides it).

Although I do see your point that now in GDScript there are two ways to do the same thing.
I'll drop the GDScript API binding for this change, so that controller vibration is only done via the ARVRController node. I'll leave java/kotlin binding since that layer doesn't have access to the ARVRController node.