bl_input

An easy way to get XR input events as callbacks in Blender. Triggers callbacks for events without requiring you to write custom actionsets, operators etc. Also sends non-XR events for convenience.

Sends events to the registered callback for common XR Controller buttons, XR Controller movement, mouse movement etc.

Installation

Copy the bl_input folder to your Blender plugin's root folder. You can then import it using import bl_input.

If you get a "module not found" error during import, please add these lines to your plugin's __init__.py, before importing bl_input:

import sys
import os

sys.path.append(os.path.dirname(__file__))

Usage

import bl_input
import bpy

def on_event(event_type: str, bl_event: bpy.types.Event):
    if event_type == "XR_ACTION":
        print("xr event", bl_event.xr.action, bl_event.value)
    elif event_type == "MOUSEMOVE":
        print("mouse move", bl_event.mouse_x, bl_event.mouse_y)

# register the event callback
bl_input.event_callback = on_event

# start XR view
bpy.ops.wm.xr_session_toggle()

# start tracking the input devices.
# **important:** this should be called only after the XR view has started!
bl_input.start_input_tracking()

Events

XR Actions

The callback will contain "XR_ACTION" as the first argument, and an instance of bpy.types.Event as the second argument.

You can access the XR event data using the xr field in the event object, which will be an instance of bpy.types.XrEventData.

The event.xr.action field will contain one of the following values (depending on the button being pressed/touched):

• "trigger"
• "squeeze"
• "joystick_x_lefthand"
• "joystick_y_lefthand"
• "joystick_x_righthand"
• "joystick_y_righthand"
• "button_a_lefthand"
• "button_b_lefthand"
• "button_a_righthand"
• "button_b_righthand"
• "button_a_touch_lefthand"
• "button_b_touch_lefthand"
• "button_a_touch_righthand"
• "button_b_touch_righthand"

Multiple events can be dispatched in parallel, for e.g. if both the trigger and squeeze buttons are being pressed.

Mouse

The callback will contain "MOUSEMOVE" as the first argument, and an instance of bpy.types.Event as the second argument.

XR Controller Movement

The callback will contain "XR_CONTROLLER_MOVE" as the first argument, and a tuple as the second argument (hand, position, rotation, context).

The tuple will contain the following values (in order): "hand" ("right" or "left"), "position" (Vector), "rotation" (Quaternion) and "context" (bpy.context).

Haptic feedback

Call bl_input.apply_haptic_feedback() to apply haptic feedback. See the function documentation for info.