plane_with_hole

marxs.visualization.utils.plane_with_hole(outer, inner)

Triangulation of a plane with an inner hole

This function constructs a triangulation for a plane with an inner hole, e.g. a rectangular plane where an inner circle is cut out.

Parameters:

outer, innernp.ndarray of shape (n, 3)

Coordinates in x,y,z of points that define the inner and outer boundary. outer and inner can have a different number of points, but points need to be listed in the same orientation (e.g. clockwise) for both and the starting points need to have a similar angle as seen from the center (e.g. for a plane with z=0, both outer and inner could list a point close to the y-axis first.

Returns:

xyznd.array

stacked outer and inner.

trianglesnd.array

List of the indices. Each row has the index of three points in xyz.

Examples

In this example, we make a square and cut out a smaller square in the middle.

>>> import numpy as np
>>> from marxs.visualization.utils import plane_with_hole
>>> outer = np.array([[-1, -1, 1, 1], [-1, 1, 1, -1], [0,0,0,0]]).T
>>> inner = 0.5 * outer
>>> xyz, triangles = plane_with_hole(outer, inner)
>>> triangles
array([[0, 4, 5],
   [0, 1, 5],
   [1, 5, 6],
   [1, 2, 6],
   [2, 6, 7],
   [2, 3, 7],
   [3, 7, 4],
   [3, 0, 4]])