PolyData.strip_connectivity

property PolyData.strip_connectivity: NumpyArray[int]

Return the connectivity array of the triangle strips.

The connectivity array stores the point ids of every strip, one strip after another and without any padding. Use strip_offsets to determine where each strip begins and ends.

Vertices, lines, faces, and strips are held in four separate cell arrays, each with its own offsets and connectivity.

Added in version 0.49.

Returns:

numpy.ndarray

Point ids that define the strips.

Notes

The returned array is read-only and cannot be modified in place. To change the connectivity, assign a new array to this property. The input is copied, so the mesh never aliases an array that may be modified later. To replace the offsets and connectivity together, assign a pyvista.CellArray to strips.

Where that copy is too expensive, assign a pyvista.CellArray built with from_arrays() and deep=False to strips, and keep a reference to the connectivity array. The mesh then wraps that array, so writing to it changes the strips without any copy. Nothing validates the point ids written this way.

Examples

Download Python source code | Download Jupyter notebook

>>> import pyvista as pv
>>> mesh = pv.Rectangle().extrude((0, 0, 1), capping=False)
>>> mesh.strip_connectivity[:4]
array([0, 1, 4, 5]...)

The array is read-only and writing to it raises a ValueError.

>>> mesh.strip_connectivity.flags['WRITEABLE']
False

Assign a new array instead. Here the first strip is wound the other way.

>>> connectivity = mesh.strip_connectivity.copy()
>>> connectivity[:4] = [1, 0, 5, 4]
>>> mesh.strip_connectivity = connectivity
>>> mesh.strip_connectivity[:4]
array([1, 0, 5, 4]...)

For a mesh large enough that the copy matters, keep the connectivity array and edit it in place.

>>> import numpy as np
>>> connectivity = np.array([0, 1, 4, 5], dtype=pv.ID_TYPE)
>>> mesh.strips = pv.CellArray.from_arrays([0, 4], connectivity, deep=False)
>>> connectivity[:] = [1, 0, 5, 4]
>>> mesh.strip_connectivity
array([1, 0, 5, 4]...)

See Also

strip_offsets

Index into this array at which each strip begins.

n_strips

Number of strips.

strips

Strips in the legacy padded format.

vert_connectivity, line_connectivity, face_connectivity

Connectivity arrays of the other PolyData cell types.

Used In

Docstring Examples

• PolyData.strip_offsets (1 use)