pyvista.DataSetFilters.extract_surface#

DataSetFilters.extract_surface(pass_pointid=True, pass_cellid=True, nonlinear_subdivision=1, progress_bar=False)[source]#

Extract surface mesh of the grid.

Parameters:

pass_pointidbool, default: True

Adds a point array "vtkOriginalPointIds" that identifies which original points these surface points correspond to.

pass_cellidbool, default: True

Adds a cell array "vtkOriginalCellIds" that identifies which original cells these surface cells correspond to.

nonlinear_subdivisionint, default: 1

If the input is an unstructured grid with nonlinear faces, this parameter determines how many times the face is subdivided into linear faces.

If 0, the output is the equivalent of its linear counterpart (and the midpoints determining the nonlinear interpolation are discarded). If 1 (the default), the nonlinear face is triangulated based on the midpoints. If greater than 1, the triangulated pieces are recursively subdivided to reach the desired subdivision. Setting the value to greater than 1 may cause some point data to not be passed even if no nonlinear faces exist. This option has no effect if the input is not an unstructured grid.

progress_barbool, default: False

Display a progress bar to indicate progress.

Returns:

pyvista.PolyData: Surface mesh of the grid.

Examples

Extract the surface of an UnstructuredGrid.

>>> import pyvista as pv
>>> from pyvista import examples
>>> grid = examples.load_hexbeam()
>>> surf = grid.extract_surface()
>>> type(surf)
<class 'pyvista.core.pointset.PolyData'>
>>> surf["vtkOriginalPointIds"]
pyvista_ndarray([ 0,  2, 36, 27,  7,  8, 81,  1, 18,  4, 54,  3,  6, 45,
                 72,  5, 63,  9, 35, 44, 11, 16, 89, 17, 10, 26, 62, 13,
                 12, 53, 80, 15, 14, 71, 19, 37, 55, 20, 38, 56, 21, 39,
                 57, 22, 40, 58, 23, 41, 59, 24, 42, 60, 25, 43, 61, 28,
                 82, 29, 83, 30, 84, 31, 85, 32, 86, 33, 87, 34, 88, 46,
                 73, 47, 74, 48, 75, 49, 76, 50, 77, 51, 78, 52, 79, 64,
                 65, 66, 67, 68, 69, 70])
>>> surf["vtkOriginalCellIds"]
pyvista_ndarray([ 0,  0,  0,  1,  1,  1,  3,  3,  3,  2,  2,  2, 36, 36,
                 36, 37, 37, 37, 39, 39, 39, 38, 38, 38,  5,  5,  9,  9,
                 13, 13, 17, 17, 21, 21, 25, 25, 29, 29, 33, 33,  4,  4,
                  8,  8, 12, 12, 16, 16, 20, 20, 24, 24, 28, 28, 32, 32,
                  7,  7, 11, 11, 15, 15, 19, 19, 23, 23, 27, 27, 31, 31,
                 35, 35,  6,  6, 10, 10, 14, 14, 18, 18, 22, 22, 26, 26,
                 30, 30, 34, 34])

Note that in the “vtkOriginalCellIds” array, the same original cells appears multiple times since this array represents the original cell of each surface cell extracted.

See the Extract Surface for more examples using this filter.