Documentation for Users: Position in 3D cartesian coordinates

General Goal : you want to create and place an object whose position is defined by its 3 cartesian coordinates (x, y, z) in the GLOBAL coordinate system (aka World coordinate system).

Specific Goal : You want to create and place a small sphere at the position of pink point P (x=0.25, y=0.20, z=0.30) as represented in figure 1 (PTVR coordinates are defined in meters by default).

PTVR code 1: function to create an object at a specific position in global coordinates

PTVR.Stimuli.Objects.Sphere (position_in_current_CS = np.array ( [0.25, 0.20, 0.30] ) ) # create a point (here a sphere) with its position

😎 Tip: Beyond this code snippet, you can look at full fonctional code of relevant demos at the end of the page.


Figure 1: Creation of the pink point P with Global coordinates.	Figure 2: Same as in figure 1 with a horizontal rotation about Y to allow a better representation of the 3D structure of the figure.

😎 Tip: In code snippet 1 above, it is assumed that the CURRENT coordinate system is the GLOBAL coordinate system (i.e. the one shown in the figure).

If you don't like the use of an array containing the three x, y and z coordinates (PTVR code 1), you can first create the object (here a sphere) and then specify its position as shown below:
PTVR code 2:

mySphere = PTVR.Stimuli.Objects.Sphere ()

mySphere.set_cartesian_coordinates (x = 0.25, y = 0.20, z = 0.30)

Demos

Python file	Description
...\PTVR_Researchers\Python_Scripts\Demos\Positions\ 1.0_create_object_in_cartesian_coord.py	create a cube in front of you : its coordinates are specified with cartesian coordinates in the Global coordinate system
...\PTVR_Researchers\Python_Scripts\Demos\Coordinate_Systems\ 10_global_cartesian_coordinate_system.py	Displays the Global coordinate system with its colored axes (red X, green Y, blue Z).

Python file

Description

...\PTVR_Researchers\Python_Scripts\Demos\Positions\ 1.0_create_object_in_cartesian_coord.py

create a cube in front of you : its coordinates are specified with cartesian coordinates in the Global coordinate system

...\PTVR_Researchers\Python_Scripts\Demos\Coordinate_Systems\ 10_global_cartesian_coordinate_system.py

Displays the Global coordinate system with its colored axes (red X, green Y, blue Z).

😎 Tip: when you click on one of the PTVR file names in the table above, a new window appears and allows you to click on the link "Go to the source code of this file" (see figure 3 below). This will directly lead you to the full raw code.

Figure 3

Links

Demos