def _process_unsplit_wing(compound, divide_closed, reloft, tol):
# Process a wing that was generated without "Split Surfs" option.
faces = compound.faces
if len(faces) != 1:
return None, None
face = faces[0]
# Get the surface.
master_surf = face.surface
# master_surf = NurbsSurface(master_surf.object)
uknots, vknots = master_surf.uknots, master_surf.vknots
vsplit = master_surf.local_to_global_param('v', 0.5)
# Segment off the end caps and the trailing edges.
u1, u2 = uknots[1], uknots[-2]
v1, v2 = vknots[1], vknots[-2]
s1 = master_surf.copy()
s1.segment(u1, u2, v1, v2)
# Reloft the surface by tessellating a curve at each spanwise knot. This
# enforces C1 continuity but assumes linear spanwise wing which may not
# support blending wing sections in newer versions of OpenVSP. Also, since
# the tessellated curves may not match up to the wing end caps making
# sewing unreliable, flat end caps are assumed.
if reloft:
s1 = _reloft_wing_surface(s1, tol)
# Generate new flat end caps using isocurves at the root and tip of
# this new surface
c0 = s1.v_iso(s1.v1)
c1 = s1.v_iso(s1.v2)
e0 = Edge.by_curve(c0)
e1 = Edge.by_curve(c1)
w0 = Wire.by_edge(e0)
w1 = Wire.by_edge(e1)
f0 = Face.by_wire(w0)
f1 = Face.by_wire(w1)
# Make faces of surfaces
f = Face.by_surface(s1)
new_faces = [f, f0, f1]
else:
# Reparamterize knots in spanwise direction to be chord length instead
# of uniform. Use isocurve at quarter-chord to determine knot values.
# This only works as long as surfaces are linear.
c0 = s1.u_iso(s1.u1)
c0.segment(vsplit, c0.u2)
qc_u = PointFromParameter(c0, vsplit, 0.25 * c0.length).parameter
c = s1.v_iso(qc_u)
pnts = [c.eval(u) for u in c.knots]
new_uknots = geom_utils.chord_parameters(pnts, 0., 1.)
s1.set_uknots(new_uknots)
# Segment off end caps
u1, u2 = uknots[0], uknots[1]
v1, v2 = vknots[1], vsplit
s2 = master_surf.copy()
s2.segment(u1, u2, v1, v2)
u1, u2 = uknots[0], uknots[1]
v1, v2 = vsplit, vknots[-2]
s3 = master_surf.copy()
s3.segment(u1, u2, v1, v2)
u1, u2 = uknots[-2], uknots[-1]
v1, v2 = vknots[1], vsplit
s4 = master_surf.copy()
s4.segment(u1, u2, v1, v2)
u1, u2 = uknots[-2], uknots[-1]
v1, v2 = vsplit, vknots[-2]
s5 = master_surf.copy()
s5.segment(u1, u2, v1, v2)
# Make faces of surfaces
new_faces = []
for s in [s1, s2, s3, s4, s5]:
f = Face.by_surface(s)
new_faces.append(f)
# Segment off TE.
u1, u2 = uknots[0], uknots[-1]
v1, v2 = vknots[0], vknots[1]
s6 = master_surf.copy()
s6.segment(u1, u2, v1, v2)
u1, u2 = uknots[0], uknots[-1]
v1, v2 = vknots[-2], vknots[-1]
s7 = master_surf.copy()
s7.segment(u1, u2, v1, v2)
# Split the TE surface at each u-knot.
usplits = occ_utils.to_tcolstd_hseq_real(uknots[1:-1])
split = ShapeUpgrade_SplitSurface()
split.Init(s6.object)
split.SetUSplitValues(usplits)
split.Perform()
comp_surf1 = split.ResSurfaces()
split = ShapeUpgrade_SplitSurface()
split.Init(s7.object)
split.SetUSplitValues(usplits)
split.Perform()
comp_surf2 = split.ResSurfaces()
# For each patch in the composite surfaces create a face.
for i in range(1, comp_surf1.NbUPatches() + 1):
for j in range(1, comp_surf1.NbVPatches() + 1):
hpatch = comp_surf1.Patch(i, j)
f = BRepBuilderAPI_MakeFace(hpatch, 0.).Face()
new_faces.append(f)
for i in range(1, comp_surf2.NbUPatches() + 1):
for j in range(1, comp_surf2.NbVPatches() + 1):
hpatch = comp_surf2.Patch(i, j)
f = BRepBuilderAPI_MakeFace(hpatch, 0.).Face()
new_faces.append(f)
# Put all faces into a compound a generate solid.
new_compound = Compound.by_shapes(new_faces)
return _build_solid(new_compound, divide_closed)
def _build_solid(compound, divide_closed):
"""
Try to build a solid from the OpenVSP compound of faces.
:param afem.topology.entities.Compound compound: The compound.
:param bool divide_closed: Option to divide closed faces.
:return: The solid.
:rtype: afem.topology.entities.Solid
"""
# Get all the faces in the compound. The surfaces must be split. Discard
# any with zero area.
faces = []
for face in compound.faces:
area = SurfaceProps(face).area
if area > 1.0e-7:
faces.append(face)
# Replace any planar B-Spline surfaces with planes.
non_planar_faces = []
planar_faces = []
for f in faces:
srf = f.surface
try:
pln = srf.as_plane()
if pln:
w = f.outer_wire
# Fix the wire because they are usually degenerate edges in
# the planar end caps.
builder = BRepBuilderAPI_MakeWire()
for e in w.edges:
if LinearProps(e).length > 1.0e-7:
builder.Add(e.object)
w = builder.Wire()
fix = ShapeFix_Wire()
fix.Load(w)
fix.SetSurface(pln.object)
fix.FixReorder()
fix.FixConnected()
fix.FixEdgeCurves()
fix.FixDegenerated()
w = Wire(fix.WireAPIMake())
fnew = Face.by_wire(w)
planar_faces.append(fnew)
else:
non_planar_faces.append(f)
except RuntimeError:
logger.info('Failed to check for planar face...')
non_planar_faces.append(f)
# Make a compound of the faces
shape = Compound.by_shapes(non_planar_faces + planar_faces)
# Split closed faces
if divide_closed:
shape = DivideClosedShape(shape).shape
# Sew shape
sewn_shape = SewShape(shape).sewed_shape
if isinstance(sewn_shape, Face):
sewn_shape = sewn_shape.to_shell()
# Attempt to unify planar domains
shell = UnifyShape(sewn_shape).shape
# Make solid
if not isinstance(shell, Shell):
logger.info('\tA valid shell was not able to be generated.')
check = CheckShape(shell)
if not check.is_valid:
logger.info('\tShape errors:')
check.log_errors()
return shell, check.invalid_shapes
solid = Solid.by_shell(shell)
# Limit tolerance
FixShape.limit_tolerance(solid)
# Check the solid and attempt to fix
invalid = []
check = CheckShape(solid)
if not check.is_valid:
logger.info('\tFixing the solid...')
solid = FixShape(solid).shape
check = CheckShape(solid)
if not check.is_valid:
logger.info('\t...solid could not be fixed.')
logger.info('\tShape errors:')
check.log_errors()
failed = check.invalid_shapes
invalid += failed
else:
tol = solid.tol_avg
logger.info(
'\tSuccessfully generated solid with tolerance={}'.format(tol))
return solid, invalid
