def test_2d():
points = numpy.array([[0.0, 0.0], [1.0, 0.0], [1.0, 1.0], [0.0, 1.0]])
constraints = [[0, 1], [1, 2], [2, 3], [3, 0]]
mesh = pygalmesh.generate_2d(points,
constraints,
cell_size=1.0e-1,
num_lloyd_steps=10)
assert mesh.points.shape == (276, 2)
assert mesh.get_cells_type("triangle").shape == (486, 3)
def square2x2():
points = numpy.array([[0.0, 0.0], [2.0, 0.0], [2.0, 2.0], [0.0, 2.0]])
constraints = [[0, 1], [1, 2], [2, 3], [3, 0]]
mesh = pygalmesh.generate_2d(
points,
constraints,
max_edge_size=0.3,
num_lloyd_steps=10,
)
print(len(mesh.points), len( mesh.get_cells_type("triangle")))
write_node(mesh.points)
write_ele(len(mesh.points), mesh.get_cells_type("triangle"))
mesh.write("square.svg")
def disk(h):
n = int(2 * numpy.pi / h)
points = numpy.array([[
numpy.cos(alpha), numpy.sin(alpha)
] for alpha in numpy.linspace(0.0, 2 * numpy.pi, n + 1, endpoint=False)])
constraints = [[k, k + 1] for k in range(n)] + [[n, 0]]
mesh = pygalmesh.generate_2d(
points,
constraints,
# Relax max_edge size a bit; with 1.5, one gets node/cell numbers comparable to
# the other mesh generators.
max_edge_size=h * 1.5,
num_lloyd_steps=0,
)
return mesh.points, mesh.get_cells_type("triangle")
def test_disk():
h = 0.1
n = int(2 * numpy.pi / h)
points = numpy.array([[
numpy.cos(alpha), numpy.sin(alpha)
] for alpha in numpy.linspace(0.0, 2 * numpy.pi, n + 1, endpoint=False)])
constraints = [[k, k + 1] for k in range(n)] + [[n, 0]]
mesh = pygalmesh.generate_2d(
points,
constraints,
max_edge_size=h,
num_lloyd_steps=0,
)
areas = compute_triangle_areas(mesh.points,
mesh.get_cells_type("triangle"))
assert numpy.all(areas > 1.0e-5)
def l_shape(h):
points = numpy.array([
[-1.0, -1.0],
[+1.0, -1.0],
[+1.0, +0.0],
[+0.0, +0.0],
[+0.0, +1.0],
[-1.0, +1.0],
])
n = len(points) - 1
constraints = [[k, k + 1] for k in range(n)] + [[n, 0]]
mesh = pygalmesh.generate_2d(
points,
constraints,
# Relax max_edge size a bit; with 1.5, one gets node/cell numbers comparable to
# the other mesh generators.
max_edge_size=h * 1.5,
num_lloyd_steps=0,
)
return mesh.points, mesh.get_cells_type("triangle")
def run_cgal(HMIN=0.01):
n = 50
points = numpy.array(
[[numpy.cos(alpha), numpy.sin(alpha)]
for alpha in numpy.linspace(0.0, 2 * numpy.pi, n, endpoint=False)])
constraints = [[k, k + 1] for k in range(n - 1)] + [[n - 1, 0]]
t1 = time.time()
mesh = pygalmesh.generate_2d(points, constraints, edge_size=HMIN)
elapsed = time.time() - t1
# mesh.write("cgal_circle.vtk")
points = mesh.points
cells = mesh.cells[0].data
num_cells = len(cells)
num_vertices = len(points)
plex = meshplex.MeshTri(points, cells)
quality = numpy.abs(plex.cell_quality)
return quality, elapsed, num_vertices, num_cells