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import numpy as np
import optimesh
import pygmsh
import meshio
# def _old_logo()
# with pygmsh.occ.Geometry() as geom:
# characteristic_length_min = 0.5
# characteristic_length_max = 0.5
#
# container = geom.add_rectangle([0.0, 0.0, 0.0], 10.0, 10.0)
#
# letter_i = geom.add_rectangle([2.0, 2.0, 0.0], 1.0, 4.5)
# i_dot = geom.add_disk([2.5, 7.5, 0.0], 0.6)
#
# disk1 = geom.add_disk([6.25, 4.5, 0.0], 2.5)
# disk2 = geom.add_disk([6.25, 4.5, 0.0], 1.5)
# letter_o = geom.boolean_difference([disk1], [disk2])
#
# geom.boolean_difference([container], [letter_i, i_dot, letter_o])
#
# mesh = pygmsh.generate_mesh(geom)
#
# X, cells = mesh.points, mesh.cells
# X, cells = optimesh.cvt.lloyd.quasi_newton_uniform_lloyd(
# X, cells["triangle"], 1.0e-3, 1000
# )
# return X, cells
def create_logo2(y=0.0):
with pygmsh.geo.Geometry() as geom:
mesh_size = 0.15
arrow1 = geom.add_polygon(
[
[0.10, 0.70 - y, 0.0],
[0.35, 0.60 - y, 0.0],
[0.35, 0.65 - y, 0.0],
[0.80, 0.65 - y, 0.0],
[0.80, 0.75 - y, 0.0],
[0.35, 0.75 - y, 0.0],
[0.35, 0.80 - y, 0.0],
],
mesh_size=mesh_size,
make_surface=False,
)
arrow2 = geom.add_polygon(
[
[0.90, 0.30 + y, 0.0],
[0.65, 0.40 + y, 0.0],
[0.65, 0.35 + y, 0.0],
[0.20, 0.35 + y, 0.0],
[0.20, 0.25 + y, 0.0],
[0.65, 0.25 + y, 0.0],
[0.65, 0.20 + y, 0.0],
],
mesh_size=mesh_size,
make_surface=False,
)
geom.add_polygon(
[[0.0, 0.0, 0.0], [1.0, 0.0, 0.0], [1.0, 1.0, 0.0], [0.0, 1.0, 0.0]],
mesh_size=mesh_size,
holes=[arrow1, arrow2],
)
mesh = geom.generate_mesh()
# return mesh.points, mesh.cells["triangle"]
X = mesh.points
cells = mesh.get_cells_type("triangle")
# np.bincount doesn't work with uint
# <https://github.com/numpy/numpy/issues/17760>
cells = cells.astype(int)
X, cells = optimesh.cvt.quasi_newton_uniform_full(
X, cells, 1.0e-10, 100, verbose=True
)
return X, cells
if __name__ == "__main__":
X, cells = create_logo2(y=0.08)
mesh = meshio.Mesh(X, {"triangle": cells})
meshio.svg.write("logo.svg", mesh, image_width=300)
X = np.column_stack([X, np.zeros_like(X[:, 0])])
meshio.Mesh(X, {"triangle": cells}).write("logo.vtk")
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