def face_normal(face):
from OCC.Core.BRepTools import breptools_UVBounds
umin, umax, vmin, vmax = breptools_UVBounds(face)
surf = BRep_Tool().Surface(face)
props = GeomLProp_SLProps(surf, (umin+umax)/2., (vmin+vmax)/2., 1, TOLERANCE)
norm = props.Normal()
if face.Orientation() == TopAbs_REVERSED:
norm.Reverse()
return norm
def normal_to_face_center(face):
u_min, u_max, v_min, v_max = breptools_UVBounds(face)
u_mid = (u_min + u_max) / 2.
v_mid = (v_min + v_max) / 2.
surf = BRep_Tool_Surface(face)
normal = GeomLProp_SLProps(surf,u_mid, v_mid,1,0.01).Normal()
if face.Orientation() == TopAbs_REVERSED:
normal.Reverse()
return normal
def is_trimmed(self):
"""
:return: True if the Wire delimiting the Face lies on the bounds
of the surface
if this is not the case, the wire represents a contour that delimits
the face [ think cookie cutter ]
and implies that the surface is trimmed
"""
_round = lambda x: round(x, 3)
a = map(_round, breptools_UVBounds(self))
b = map(_round, self.adaptor.Surface().Surface().GetObject().Bounds())
if a != b:
print('a,b', a, b)
return True
return False
def sample_point(face):
# randomly choose a point from F
u_min, u_max, v_min, v_max = breptools_UVBounds(face)
u = random.uniform(u_min, u_max)
v = random.uniform(v_min, v_max)
itool = IntTools_FClass2d(face, 1e-6)
while itool.Perform(gp_Pnt2d(u,v)) != 0:
print('outside')
u = random.uniform(u_min, u_max)
v = random.uniform(v_min, v_max)
P = BRepAdaptor_Surface(face).Value(u, v)
# the normal
surf = BRep_Tool_Surface(face)
D = GeomLProp_SLProps(surf,u,v,1,0.01).Normal()
if face.Orientation() == TopAbs_REVERSED:
D.Reverse()
return P, D
def domain(self):
'''the u,v domain of the curve
:return: UMin, UMax, VMin, VMax
'''
return breptools_UVBounds(self)