Quick start

Installation

Install using pip

pip install tnsgrt

See matplotlib and vispy for tweaking visualization settings.

Source code

Code corresponding to the sections in this guide are distributed in the form of Jupiter notebooks and can be found at the examples directory in the source code repo.

Hello World

Try the following code

from tnsgrt.prism import Prism
s = Prism()

The object s is a tnsgrt.structure.Structure representing a Snelson Tensegrity Prism with three bars and nine strings such as the one in the following figure:

The structure can be visualized using matplotlib

from matplotlib import pyplot as plt
# add your favorite matplotlib magic below
%matplotlib widget

and tnsgrt.plotter.MatplotlibPlotter

from tnsgrt.plotter.matplotlib import MatplotlibPlotter

to produce a 3D plot like the one in the figure above

plotter = MatplotlibPlotter()
plotter.plot(s)
plt.axis('equal')
plt.axis('off')
plt.show()

The underlying figure and axis can be retrieved and used to manipulate the plot

fig, ax = plotter.get_handles()
ax.view_init(elev=20, azim=45, roll=0)
plt.show()

which in this case rotates the plot to obtain the better viewpoint

Prisms, lots of prisms

It is possible to construct Snelson prisms with different number of bars

prisms = [Prism(n) for n in (3, 4, 6, 12)]

All prisms are constructed centered at the origin. They can be translated

import numpy as np
prisms = [prism.translate(np.array([3*i,0,0])) for i, prism in enumerate(prisms)]

before plotting

plotter = MatplotlibPlotter()
plotter.plot(prisms)
plt.axis('equal')
plt.axis('off')
plt.show()
fig, ax = plotter.get_handles()
ax.view_init(elev=30, azim=60)
ax.set_box_aspect(None, zoom=1.8)

to produce a plot such as:

Plotting with VisPy

It is also possible to plot structures using VisPy. Certain users might need to tweak their installations. See installation instructions for details.

The above prisms can be plotted with VisPy

from IPython.display import display
import jupyter_rfb
from tnsgrt.plotter.vispy import VisPyPlotter
plotter = VisPyPlotter(scene={'size': (800,200), 'app': 'jupyter_rfb'},
                       camera={'scale_factor': 6, 'center': (4.5,2,0)})
plotter.plot(prisms)
plotter.get_canvas()