def face_normal(face):
from OCCT.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 radius_at_uv(face, u, v):
'''
returns the mean radius at a u,v coordinate
@param face: surface input
@param u,v: u,v coordinate
'''
h_srf = BRep_Tool().Surface(face)
#uv_domain = GeomLProp_SurfaceTool().Bounds(h_srf)
curvature = GeomLProp_SLProps(h_srf, u, v, 1, 1e-6)
try:
_crv_min = 1. / curvature.MinCurvature()
except ZeroDivisionError:
_crv_min = 0.
try:
_crv_max = 1. / curvature.MaxCurvature()
except ZeroDivisionError:
_crv_max = 0.
return abs((_crv_min + _crv_max) / 2.)
def curvature(self, u, v):
'''returns the curvature at the u parameter
the curvature object can be returned too using
curvatureType == curvatureType
curvatureTypes are:
gaussian
minimum
maximum
mean
curvatureType
'''
if not self._curvature_initiated:
self._curvature = GeomLProp_SLProps(self.instance.surface_handle,
u, v, 2, 1e-7)
_domain = self.instance.domain()
if u in _domain or v in _domain:
print('<<<CORRECTING DOMAIN...>>>')
div = 1000
delta_u, delta_v = (_domain[0] - _domain[1]) / div, (
_domain[2] - _domain[3]) / div
if u in _domain:
low, hi = u - _domain[0], u - _domain[1]
if low < hi:
u = u - delta_u
else:
u = u + delta_u
if v in _domain:
low, hi = v - _domain[2], v - _domain[3]
if low < hi:
v = v - delta_v
else:
v = v + delta_v
self._curvature.SetParameters(u, v)
self._curvature_initiated = True
return self._curvature
class DiffGeomSurface(object):
def __init__(self, instance):
self.instance = instance
self._curvature = None
self._curvature_initiated = False
def curvature(self, u, v):
'''returns the curvature at the u parameter
the curvature object can be returned too using
curvatureType == curvatureType
curvatureTypes are:
gaussian
minimum
maximum
mean
curvatureType
'''
if not self._curvature_initiated:
self._curvature = GeomLProp_SLProps(self.instance.surface_handle,
u, v, 2, 1e-7)
_domain = self.instance.domain()
if u in _domain or v in _domain:
print('<<<CORRECTING DOMAIN...>>>')
div = 1000
delta_u, delta_v = (_domain[0] - _domain[1]) / div, (
_domain[2] - _domain[3]) / div
if u in _domain:
low, hi = u - _domain[0], u - _domain[1]
if low < hi:
u = u - delta_u
else:
u = u + delta_u
if v in _domain:
low, hi = v - _domain[2], v - _domain[3]
if low < hi:
v = v - delta_v
else:
v = v + delta_v
self._curvature.SetParameters(u, v)
self._curvature_initiated = True
return self._curvature
def gaussian_curvature(self, u, v):
return self.curvature(u, v).GaussianCurvature()
def min_curvature(self, u, v):
return self.curvature(u, v).MinCurvature()
def mean_curvature(self, u, v):
return self.curvature(u, v).MeanCurvature()
def max_curvature(self, u, v):
return self.curvature(u, v).MaxCurvature()
def normal(self, u, v):
# TODO: should make this return a gp_Vec
curv = self.curvature(u, v)
if curv.IsNormalDefined():
return curv.Normal()
else:
raise ValueError('normal is not defined at u,v: {0}, {1}'.format(
u, v))
def tangent(self, u, v):
dU, dV = gp_Dir(), gp_Dir()
curv = self.curvature(u, v)
if curv.IsTangentUDefined() and curv.IsTangentVDefined():
curv.TangentU(dU), curv.TangentV(dV)
return dU, dV
else:
return None, None
def radius(self, u, v):
'''returns the radius at u
'''
# TODO: SHOULD WE RETURN A SIGNED RADIUS? ( get rid of abs() )?
try:
_crv_min = 1. / self.min_curvature(u, v)
except ZeroDivisionError:
_crv_min = 0.
try:
_crv_max = 1. / self.max_curvature(u, v)
except ZeroDivisionError:
_crv_max = 0.
return abs((_crv_min + _crv_max) / 2.)