def make_offset(wire_or_face,
offsetDistance,
altitude=0,
joinType=GeomAbs_Arc):
"""
builds a offsetted wire or face from a wire or face
construct an offsetted version of the shape
@param wire_or_face: the wire or face to offset
@param offsetDistance: the distance to offset
@param altitude: move the offsetted shape to altitude
from the normal of the wire or face
@param joinType: the type of offset you want
can be one of GeomAbs_Arc, GeomAbs_Tangent, GeomAbs_Intersection
note: a shape that has a negative offsetDistance will return
a sharp corner
"""
_joints = [GeomAbs_Arc, GeomAbs_Tangent, GeomAbs_Intersection]
assert joinType in _joints, '%s is not one of %s' % (joinType, _joints)
try:
offset = BRepOffsetAPI_MakeOffset(wire_or_face, joinType)
offset.Perform(offsetDistance, altitude)
if offset.IsDone():
return ST(offset.Shape())
else:
return None
except RuntimeError('failed to offset shape'):
return None
def update_shape(self, change={}):
d = self.declaration
#: Get the shape to apply the fillet to
s = self.get_shape()
if isinstance(s.shape, BRepBuilderAPI_MakeWire):
shape = BRepOffsetAPI_MakeOffset(s.shape.Wire(),
self.join_types[d.join_type])
shape.Perform(d.offset)
self.shape = shape
else:
self.shape = BRepOffsetAPI_MakeOffsetShape(
s.shape.Shape() if hasattr(s.shape, 'Shape') else s.shape,
d.offset, d.tolerance, self.offset_modes[d.offset_mode],
d.intersection, False, self.join_types[d.join_type])
def create_offsets(face, nr_of_counters, distance_between_contours):
offset = BRepOffsetAPI_MakeOffset()
offset.Init(GeomAbs_Arc)
for wi in TopologyExplorer(face).wires():
offset.AddWire(wi)
for i in range(nr_of_counters):
offset.Perform(-distance_between_contours * i)
if offset.IsDone():
yield offset.Shape()