def MakeHexagonalMesh2D(maxh=0.1):
geo = SplineGeometry()
pnums = [
geo.AddPoint(math.cos(phi), math.sin(phi))
for phi in [xx * math.pi / 3 for xx in range(6)]
]
l1 = geo.Append(["line", 0, 1],
leftdomain=1,
rightdomain=0,
bc="upperRight")
geo.Append(["line", 4, 3],
leftdomain=0,
rightdomain=1,
bc="lowerLeft",
copy=l1)
l2 = geo.Append(["line", 1, 2],
leftdomain=1,
rightdomain=0,
bc="upperCenter")
geo.Append(["line", 5, 4],
leftdomain=0,
rightdomain=1,
bc="lowerCenter",
copy=l2)
l3 = geo.Append(["line", 2, 3],
leftdomain=1,
rightdomain=0,
bc="upperLeft")
geo.Append(["line", 0, 5],
leftdomain=0,
rightdomain=1,
bc="lowerRight",
copy=l3)
return geo.GenerateMesh(maxh=maxh)
from ngsolve import *
from netgen.geom2d import SplineGeometry
from math import sqrt
geo = SplineGeometry()
s = 0.3
Points = [(-s/2,-sqrt(3)/6*s),(s/2,-sqrt(3)/6*s),(0,sqrt(3)/3*s),
(-s/2*4,-sqrt(3)/6*s*4),(s/2*4,-sqrt(3)/6*s*4),(0,sqrt(3)/3*s*4),
(-s/2*6,-sqrt(3)/6*s*6),(s/2*6,-sqrt(3)/6*s*6),(0,sqrt(3)/3*s*6)]
for pnt in Points:
geo.AddPoint(*pnt)
for pids in [[0,1],[1,2],[2,0]]:
geo.Append(["line"]+pids,leftdomain=0,rightdomain=1,bc="scatterer")
for pids in [[3,4],[4,5],[5,3]]:
geo.Append(["line"]+pids,leftdomain=1,rightdomain=2)
for pids in [[6,7],[7,8],[8,6]]:
geo.Append(["line"]+pids,leftdomain=2,rightdomain=0)
ngmesh = geo.GenerateMesh(maxh=0.04)
# ngmesh.Save("scattering.vol")
mesh = Mesh(ngmesh)
# mesh = Mesh ("scattering.vol")
p=pml.HalfSpace(point=(0,4/3*sqrt(3)*s),normal=(sqrt(3),1),alpha=0.5j)+pml.HalfSpace(point=(0,4/3*sqrt(3)*s),normal=(-sqrt(3),1),alpha=0.5j)+pml.HalfSpace(point=(0,-sqrt(3)*s*2/3),normal=(0,-1),alpha=0.5j)
print(p)
mesh.SetPML(p,definedon=2)
