def make_loft(elements,
ruled=False,
tolerance=TOLERANCE,
continuity=GeomAbs_C2,
check_compatibility=True):
sections = BRepOffsetAPI_ThruSections(False, ruled, tolerance)
for i in elements:
if isinstance(i, TopoDS_Wire):
sections.AddWire(i)
elif isinstance(i, TopoDS_Vertex):
sections.AddVertex(i)
else:
raise TypeError(
'elements is a list of TopoDS_Wire or TopoDS_Vertex, found a %s fool'
% i.__class__)
sections.CheckCompatibility(check_compatibility)
sections.SetContinuity(continuity)
sections.Build()
with assert_isdone(sections, 'failed lofting'):
te = ShapeToTopology()
loft = te(sections.Shape())
return loft
anEdge2OnSurf2 = BRepBuilderAPI_MakeEdge(aSegment.Value(),
Handle_Geom_Surface(aCyl2))
threadingWire1 = BRepBuilderAPI_MakeWire(anEdge1OnSurf1.Edge(),
anEdge2OnSurf1.Edge())
threadingWire2 = BRepBuilderAPI_MakeWire(anEdge1OnSurf2.Edge(),
anEdge2OnSurf2.Edge())
# Compute the 3D representations of the edges/wires
breplib.BuildCurves3d(threadingWire1.Shape())
breplib.BuildCurves3d(threadingWire2.Shape())
# Create the surfaces of the threading
aTool = BRepOffsetAPI_ThruSections(True)
aTool.AddWire(threadingWire1.Wire())
aTool.AddWire(threadingWire2.Wire())
aTool.CheckCompatibility(False)
myThreading = aTool.Shape()
# Build the resulting compound
aRes = TopoDS_Compound()
aBuilder = BRep_Builder()
aBuilder.MakeCompound(aRes)
aBuilder.Add(aRes, myBody.Shape())
aBuilder.Add(aRes, myThreading)
display, start_display, add_menu, add_function_to_menu = init_display('wx')
display.DisplayColoredShape(aRes)
start_display()
def AddSurfaceLoft(objs, continuity=GeomAbs_C2, check_compatibility=True,
solid=True, first_vertex=None, last_vertex=None,
max_degree=8, close_sections=True):
"""Create a lift surface through curve objects
Parameters
----------
objs : list of python classes
Each obj is expected to have an obj.Curve attribute :
see airconics.primitives.airfoil class
continuity : OCC.GeomAbs.GeomAbs_XX type (default C2)
The order of continuity (C^0, C^1, C^2, G^0, ....)
check_compatibility : bool (default=True)
Adds a surface compatibility check to the builder
solid : bool (default=True)
Creates a solid object from the loft if True
first_vertex : TopoDS_Vertex (optional, default=None)
The starting vertex of the surface to add to the 'ThruSections'
algorithm
last_vertex : TopoDS_Vertex (optional, default=None)
The end vertex of the surface to add to the 'ThruSections'
algorithm
max_degree : int (default=8)
The order of the fitted NURBS surface
close_sections : bool (default=True):
Connects the start and end point of the loft rib curves if true. This
has the same effect as adding an airfoil trailing edge.
Returns
-------
shape : TopoDS_Shape
The generated loft surface
Notes
-----
Uses OCC.BRepOffsetAPI.BRepOffsetAPI_ThruSections. This function is
ORDER DEPENDANT, i.e. add elements in the order through which they should
be lofted
"""
assert (len(objs) >= 2), 'Loft Failed: Less than two input curves'
# Note: This is to give a smooth loft.
ruled = False
pres3d = 1e-6
args = [solid, ruled, pres3d] # args (in order) for ThruSections
generator = BRepOffsetAPI_ThruSections(*args)
generator.SetMaxDegree(max_degree)
# from OCC.GeomAbs import GeomAbs_G1
generator.SetParType(Approx_ChordLength)
if first_vertex:
generator.AddVertex(first_vertex)
for obj in objs:
try:
# Check if this is an airconics object with a GeomBspline handle
# as its 'Curve' attribute
obj = obj.Curve
# edge = [make_edge(obj)]
except:
# Assume the object is already a geombspline handle
pass
# try:
# # If working with an airconics object, the OCC curve is stored
# # in obj.Curve:
edges = [make_edge(obj)]
if close_sections:
crv = obj.GetObject()
if crv.IsClosed() is False:
# Add Finite TE edge
TE = make_edge(crv.Value(1), crv.Value(0))
edges.append(TE)
generator.AddWire(BRepBuilderAPI_MakeWire(*edges).Wire())
# else:
# generator
if last_vertex:
generator.AddVertex(last_vertex)
generator.CheckCompatibility(check_compatibility)
generator.SetContinuity(continuity)
generator.Build()
with assert_isdone(generator, 'failed lofting'):
return generator.Shape()