fillet tangency creates poorly conditioned mesh
Issue #94
new
Attempting to create a fillet with a circle subtraction can produce an nearly infinitely fine mesh at the tangency point.
Code to reproduce, issue is at location (14.5,30)
from dolfin import *
import mshr
import matplotlib.pyplot as plt
s = mshr.Rectangle(Point(0,100),Point(14.5,0))
fill = mshr.Rectangle(Point(0,120),Point(44.5,30))
fillet = mshr.Circle(Point(44.5,30),30,20)
plot(mshr.generate_mesh((s+fill)-fillet,30))
plt.show()
first zoom spanning 20 units
second zoom spanning 0.025 units
The mesh is almost infinitely self similar until it starts to approach 1e-13.
Changing the mesh resolution can cause crashing.
Attempts at reproduction with other similar geometries do not do this.