laser_beam_axis.py

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# -*- coding: utf-8 -*-
"""
...\PTVR_Researchers\Python_Scripts\Demos\Pointing\laser_beam_axis.py
 
 
Goal : show how to change the axis of the laser beam with respect to the
        reference axis of the handcontroller.
        This is achieved in the PointingLaser object with the 
        'laser_beam_x_y_rotation' parameter.
        This modification only affects the VISUAL appearance of the laser beam.
       
       The axis of the laser beam can be defined with rotation coordinates or
       with perimetric coordinates wrt the handcontroller reference axis.
       
Task:  Modify the values of 'my_laser_axis_wrt_handcontroller_reference_axis',
    and see how it modifies the axis of the laser beam (this modification is 
    dependent on the headset manufacturer (see below) .
       
Note 1: 
    For the the HTC Vive Pro series pointers, the reference axis 
    of the handcontroller is aligned with the long axis of the handcontroller.
    
    For the Quest 1, 2 and 3 headsets, the reference axis of 
    the handcontroller is tilted about the X axis of the handcontroller.
 
Note 2:
       In this demo, the laser beam is tilted by 45 degrees about the x axis
       of the handcontroller (as specified by x and y rotations)
 
Important note concerning scripts that use handcontrollers:
    It is necessary to specify your VR system's manufacturer if: 
        a/ your code contains a PointedAt Event triggered by a handcontroller
        or
        b/ your code contains a PointingLaser () object.
    This is specified in the The3DWorld() in the following way:
    headset_manufacturer = "Vive" (default) refers to the HTC Vive pro series headsets.
    headset_manufacturer = "Oculus" refers to the Quest 1, 2 or 3 headsets (in keeping 
    with OpenXR terminology).
    For example:
my_world = The3DWorld ( 
                headset_manufacturer = "Vive" # "Vive" by default
            )
 
 
Things to check in the PointingLaser object when using different 
    headset manufacturers:
    ex. With the Quest, you should do 
    laser_beam_x_y_rotation = np.array([60, 0]) # 60 ° about X axis
    in the PointingLaser () object.
    Otherwise the laserbeam will be directed upwards in an awkward and non
    ergonomic direction.
 
 
"""
 
 
from PTVR.Visual import The3DWorld
from PTVR.Stimuli.Scenes import VisualScene
import numpy as np
 
from PTVR.Pointing.PointingCursor import PointingLaser
from PTVR.SystemUtils import LaunchThe3DWorld
 
 
# =============================================================================
#                               PARAMETERS                                    #
# =============================================================================
 
# Laser parameters
#
# Axis of laser beam with respect to the handcontroller reference axis.
# either perimetric coordinates : eccentricity and half-meridian (values from 0 to 360)
# or rotation values about x and y axes of the handcontroller (values from 0 to 360)
my_laser_axis_wrt_handcontroller_reference_axis = np.array([45, 0])  
    # the default is : np.array([45, 0])
# The two coordinates of this variable are interpreted as perimetric or 
# rotation values depending on the following variable.
 
 
flag_x_y_rotation_coordinates = True
# Allows the interpretation of the 2 values in 
# 'my_laser_axis_wrt_handcontroller_reference_axis'.
# if true -> rotations about the x and y axis 
# if False -> perimetric coordinates (eccentricity and half-meridian)
 
# =============================================================================
#                              END PARAMETERS                                 #
# =============================================================================
 
my_world = The3DWorld(
    headset_manufacturer = "Vive"  
    # "Vive" (default) or "Oculus" or "ViveFocusVision"
)
# It is necessary to specify your VR system's manufacturer (here "Vive")
# in the The3DWorld() object if: 
#     a/ your code contains a PointedAt Event triggered by a handcontroller
#     or
#     b/ your code contains a PointingLaser () Object.
 
 
def main():
 
    my_scene = VisualScene(
        is_right_hand_controller_visible = True,
    )
 
    # Create a pointer
    if (flag_x_y_rotation_coordinates == True):  # x and y rotation coordinates
        my_laser_beam = PointingLaser(
            # x and y rotation values about x and y axes of the handcontroller (values from 0 to 360)
            laser_beam_x_y_rotation = my_laser_axis_wrt_handcontroller_reference_axis
        )
    if (flag_x_y_rotation_coordinates == False):  # perimetric coordinates
        my_laser_beam = PointingLaser(
            # perimetric coordinates : eccentricity and half-meridian (values from 0 to 360)
            laser_beam_ecc_hm = my_laser_axis_wrt_handcontroller_reference_axis
        )
 
    my_scene.place_pointing_laser(my_laser_beam)
 
    my_world.add_scene(my_scene)
    my_world.write()
 
 
if __name__ == "__main__":
    main()
    LaunchThe3DWorld()  # Launch the Experiment with PTVR.