Mesh refinement does not work for GeometryList with inners

[grongen]

MeshKernel does not refine a mesh with with a GeometryList that contains an inner (a polygon with a hole)

To reproduce, run the code at the bottom. The plot below results from the code. The left one is the base mesh. The middle one refined correcly, based on a GeometryList object without inners. The right one does not refine, as a GeometryList object with inner is provided.

Version info:

• OS: Windows
• Version: meshkernel 1.0.0

Script to test
`# Import modules
import meshkernel as mk
import matplotlib.pyplot as plt
import numpy as np

Polygons

outer = mk.GeometryList(
x_coordinates=np.array([2.5, 6.5, 7.5, 1.5, 2.5]), y_coordinates=np.array([2.5, 1.5, 6.5, 7.5, 2.5])
)

inner = mk.GeometryList(
x_coordinates=np.array([4.0, 6.0, 6.0, 4.0, 4.0])-0.2, y_coordinates=np.array([4.0, 4.0, 6.0, 6.0, 4.0])-0.2,
)

holed = mk.GeometryList(
x_coordinates=np.concatenate([outer.x_coordinates, [outer.inner_outer_separator], inner.x_coordinates]),
y_coordinates=np.concatenate([outer.y_coordinates, [outer.inner_outer_separator], inner.y_coordinates]),
)

Refinement parameters

parameters = mk.MeshRefinementParameters(
refine_intersected=True,
use_mass_center_when_refining=False,
min_face_size=10.0, # Does nothing?
refinement_type=1, # No effect?
connect_hanging_nodes=True,
account_for_samples_outside_face=False,
max_refinement_iterations=1,
)

Meshkernel

meshkernel = mk.MeshKernel()

Function to create base mesh

def generate_base_mesh():
mesh2d_input = mk.Mesh2dFactory.create_rectilinear_mesh(
rows=10,
columns=10,
origin_x=0,
origin_y=0,
spacing_x=1,
spacing_y=1,
)
return mesh2d_input

Create base mesh

mesh2d_input = generate_base_mesh()
meshkernel.mesh2d_set(mesh2d_input)
mesh2d_base = meshkernel.mesh2d_get()

Create refined mesh

mesh2d_input = generate_base_mesh()
meshkernel.mesh2d_set(mesh2d_input)
meshkernel.mesh2d_refine_based_on_polygon(outer, parameters)
mesh2d_refined = meshkernel.mesh2d_get()

Create mesh that should be refined based on holed polygon

mesh2d_input = generate_base_mesh()
meshkernel.mesh2d_set(mesh2d_input)
meshkernel.mesh2d_refine_based_on_polygon(holed, parameters)
mesh2d_should_be_refined = meshkernel.mesh2d_get()

Plot

fig, axs = plt.subplots(ncols=3, figsize=(13.5, 5), constrained_layout=True)
for ax in axs:
ax.set(aspect=1.0)

mesh2d = meshkernel.mesh2d_get()
ax = axs[0]
mesh2d_base.plot_edges(ax=ax)

ax = axs[1]
mesh2d = meshkernel.mesh2d_get()
mesh2d_refined.plot_edges(ax=ax)
ax.plot(outer.x_coordinates, outer.y_coordinates, color='k')

ax = axs[2]
mesh2d_should_be_refined.plot_edges(ax=ax)
ax.plot(outer.x_coordinates, outer.y_coordinates, color='k')
ax.plot(inner.x_coordinates, inner.y_coordinates, color='k')`