vxa_generator.py is a simple script that generates a .vxa file that can be used to load stable parameters into voxcraft-viz to visualize voxelbots composed of two materials: active (actuating) voxels and passive voxels.
The script can be directly run in which case it produces a file named a.vxa with a single actuating voxel. This file can then be passed into voxcraft-viz for visualization. For example:
python vxa_generator.py
voxcraft-viz a.vxa
You can then go into draw mode to draw a robot and visualize it in the Physics Sandbox with the stable parameters set by a.vxa.
The script can also be used to load in a robot body specified by a 3-Dimensional NumPy array. In this case, the function vxa_from_array() can be called from a different program with the 3D body array as an argument. This produces a .vxa file with the specified body and stable parameters. The filename can be specified, otherwise it will be a.vxa. For example, suppose we have the following script my_bot.py:
import numpy as np
from vxa_generator import vxa_from_array
body = np.zeros((2,2,2)) # body is a 2x2x2 cube
body[:,:,0]=1 # bottom layer is active
body[:,:,1]=2 # top layer is passive
vxa_from_array(body, save_filename='my_bot.vxa')
We can run the above script and pass in the resulting .vxa file into voxcraft-viz to visualize our bot as follows:
python my_bot.py
voxcraft-viz my_bot.vxa
You have to enable self collisions yourself by clicking the Enable Self Collision check box in the Physics Settings.