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Vector Quantities

Visualize vector-valued data at the nodes or edges of a curve network.

Example: 

import numpy as np
import polyscope as ps
ps.init()

# register a curve network 
N_node = 100
N_edge = 250
nodes = np.random.rand(N_node, 3)
edges = np.random.randint(0, N_node, size=(N_edge,2))
ps_net = ps.register_curve_network("my network", nodes, edges)

# visualize some random vectors per-node
vecs_node = np.random.rand(N_node, 3)
ps_net.add_vector_quantity("rand vecs", vecs_node, enabled=True)

# visualize some random vectors per-edge
vecs_edge = np.random.rand(N_edge, 3)
ps_net.add_vector_quantity("rand vecs edge", vecs_edge, defined_on='edges')

# set radius/length/color of the vectors
ps_net.add_vector_quantity("rand vecs opt", vecs_node, radius=0.001, length=0.005, color=(0.2, 0.5, 0.5))

# ambient vectors don't get auto-scaled, useful e.g. when representing offsets in 3D space
ps_net.add_vector_quantity("vecs ambient", vecs_node, vectortype='ambient')

# view the network with all of these quantities
ps.show()

CurveNetwork.add_vector_quantity(name, values, defined_on='nodes', enabled=None, vectortype="standard", length=None, radius=None, color=None)

Add a vector quantity to the network.

  • name string, a name for the quantity
  • values an Nx3 numpy array, vectors at nodes/edges (or Nx2 for 2D data)
  • defined_on string, one of nodes or edges, is this data a vector per-node or a vector per-edge?

This function also accepts optional keyword arguments listed below, which customize the appearance and behavior of the quantity.

Vector Quantity Options

When adding a vector quantity, the following keyword options can be set. These are available for all kinds of vector quantities on all structures.

Keyword arguments:

  • enabled boolean, whether the quantity is initially enabled (Default: false)
  • vectortype, one of "standard" or "ambient". Ambient vectors don’t get auto-scaled, and thus are good for representing values in absolute 3D world coordinates. (Default: "standard")
  • length float, a (relative) length for the vectors
  • radius float, a (relative) radius for the vectors
  • color 3-tuple, color for the vectors

If not specified, these optional parameters will assume a reasonable default value, or a persistent value if previously set.