def vertex_fillet(cube, vert):
# apply a fillet on incident edges on a vertex
afillet = BRepFilletAPI_MakeFillet(cube)
cnt = 0
# find edges from vertex
_map = TopTools_IndexedDataMapOfShapeListOfShape()
topexp_MapShapesAndAncestors(cube, TopAbs_VERTEX, TopAbs_EDGE, _map)
results = _map.FindFromKey(vert)
topology_iterator = TopTools_ListIteratorOfListOfShape(results)
while topology_iterator.More():
edge = topods_Edge(topology_iterator.Value())
topology_iterator.Next()
first, last = topexp_FirstVertex(edge), topexp_LastVertex(edge)
vertex, first_vert, last_vert = BRep_Tool().Pnt(vert), BRep_Tool().Pnt(
first), BRep_Tool().Pnt(last)
if edge.Orientation():
if not vertex.IsEqual(first_vert, 0.001):
afillet.Add(0, 20., edge)
else:
afillet.Add(20, 0, edge)
cnt += 1
afillet.Build()
if afillet.IsDone():
return afillet.Shape()
else:
raise AssertionError('you failed on me you fool!')
def project_curve(self, other):
# this way Geom_Circle and alike are valid too
if (isinstance(other, TopoDS_Edge) or isinstance(other, Geom_Curve)
or issubclass(other, Geom_Curve)):
# convert edge to curve
first, last = topexp.FirstVertex(other), topexp.LastVertex(other)
lbound, ubound = BRep_Tool().Parameter(
first, other), BRep_Tool().Parameter(last, other)
other = BRep_Tool.Curve(other, lbound, ubound).GetObject()
return geomprojlib.Project(other, self.surface_handle)
def sort_edges_into_order(occedgelist, isclosed=False):
from OCC.TopoDS import topods
from OCC.TopExp import topexp
from OCC.BRep import BRep_Tool
from OCC.ShapeAnalysis import ShapeAnalysis_WireOrder
from OCC.Precision import precision
sawo_statusdict = {
0: "all edges are direct and in sequence",
1: "all edges are direct but some are not in sequence",
2: "unresolved gaps remain",
-1: "some edges are reversed, but no gaps remain",
-2: "some edges are reversed and some gaps remain",
-10: "failure on reorder"
}
mode3d = True
SAWO = ShapeAnalysis_WireOrder(mode3d, precision.PConfusion())
for occedge in occedgelist:
V1 = topexp.FirstVertex(topods.Edge(occedge))
V2 = topexp.LastVertex(topods.Edge(occedge))
pnt1 = BRep_Tool().Pnt(V1)
pnt2 = BRep_Tool().Pnt(V2)
SAWO.Add(pnt1.XYZ(), pnt2.XYZ())
SAWO.SetKeepLoopsMode(True)
SAWO.Perform(isclosed)
#print "SAWO.Status()", SAWO.Status()
if not SAWO.IsDone():
raise RuntimeError, "build wire: Unable to reorder edges: \n" + sawo_statusdict[
SAWO.Status()]
else:
if SAWO.Status() not in [0, -1]:
pass # not critical, wirebuilder will handle this
SAWO.SetChains(precision.PConfusion())
sorted_edge2dlist = []
#print "Number of chains: ", SAWO.NbChains()
for i in range(SAWO.NbChains()):
sorted_edges = []
estart, eend = SAWO.Chain(i + 1)
#print "Number of edges in chain", i, ": ", eend - estart + 1
if (eend - estart + 1) == 0:
continue
for j in range(estart, eend + 1):
idx = abs(SAWO.Ordered(j))
edge2w = occedgelist[idx - 1]
if SAWO.Ordered(j) < 0:
edge2w.Reverse()
sorted_edges.append(edge2w)
sorted_edge2dlist.append(sorted_edges)
return sorted_edge2dlist
def project_curve(self, other):
# this way Geom_Circle and alike are valid too
if isinstance(other, TopoDS_Edge) or\
isinstance(other, Geom_Curve) or\
issubclass(other, Geom_Curve):
if isinstance(other, TopoDS_Edge):
# convert edge to curve
first, last = TopExp.FirstVertex(other), TopExp.LastVertex(other)
lbound, ubound = BRep_Tool().Parameter(first, other), BRep_Tool().Parameter(first, other)
other = BRep_Tool.Curve(other, lbound, ubound).GetObject()
from OCC.GeomProjLib import GeomProjLib
return GeomProjLib().Project(other, self.surface_handle)
def curve(self):
if self._curve is not None and not self.is_dirty:
pass
else:
self._curve_handle = BRep_Tool().Curve(self)[0]
self._curve = self._curve_handle.GetObject()
return self._curve
def pcurve(self, face):
"""
computes the 2d parametric spline that lies on the surface of the face
:return: Geom2d_Curve, u, v
"""
crv, u, v = BRep_Tool().CurveOnSurface(self, face)
return crv.GetObject(), u, v
def simple_mesh(occshape, mesh_incremental_float=0.8):
#TODO: figure out why is it that some surfaces do not work
occshape = TopoDS_Shape(occshape)
bt = BRep_Tool()
BRepMesh_IncrementalMesh(occshape, mesh_incremental_float)
occshape_face_list = fetch.geom_explorer(occshape, "face")
occface_list = []
for occshape_face in occshape_face_list:
location = TopLoc_Location()
#occshape_face = modify.fix_face(occshape_face)
facing = bt.Triangulation(occshape_face, location).GetObject()
if facing:
tab = facing.Nodes()
tri = facing.Triangles()
for i in range(1, facing.NbTriangles() + 1):
trian = tri.Value(i)
index1, index2, index3 = trian.Get()
#print index1, index2, index3
pypt1 = fetch.occpt2pypt(tab.Value(index1))
pypt2 = fetch.occpt2pypt(tab.Value(index2))
pypt3 = fetch.occpt2pypt(tab.Value(index3))
#print pypt1, pypt2, pypt3
occface = make_polygon([pypt1, pypt2, pypt3])
occface_list.append(occface)
return occface_list
def occ_triangle_mesh(event=None):
#
# Mesh the shape
#
BRepMesh_IncrementalMesh(aShape, 0.1)
builder = BRep_Builder()
Comp = TopoDS_Compound()
builder.MakeCompound(Comp)
ex = TopExp_Explorer(aShape, TopAbs_FACE)
while ex.More():
F = topods_Face(ex.Current())
L = TopLoc_Location()
facing = (BRep_Tool().Triangulation(F, L)).GetObject()
tab = facing.Nodes()
tri = facing.Triangles()
for i in range(1, facing.NbTriangles() + 1):
trian = tri.Value(i)
#print trian
index1, index2, index3 = trian.Get()
for j in range(1, 4):
if j == 1:
M = index1
N = index2
elif j == 2:
N = index3
elif j == 3:
M = index2
ME = BRepBuilderAPI_MakeEdge(tab.Value(M), tab.Value(N))
if ME.IsDone():
builder.Add(Comp, ME.Edge())
ex.Next()
display.DisplayShape(Comp, update=True)
def face_normal(face):
umin, umax, vmin, vmax = BRepTools.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 uv_from_projected_point_on_face(face, pt):
'''
returns the uv coordinate from a projected point on a face
'''
srf = BRep_Tool().Surface(face)
sas = ShapeAnalysis_Surface(srf)
uv = sas.ValueOfUV(pt, 1e-2)
print('distance ', sas.Value(uv).Distance(pt))
return uv.Coord()
def process_wire(wire):
'''takes a wire and extracts points
returns a list of points'''
vertices = []
explorer = BRepTools_WireExplorer(wire)
while explorer.More():
vertex = TopoDS().Vertex(explorer.CurrentVertex())
xyz = Point(BRep_Tool().Pnt(vertex))
vertices.append(xyz)
explorer.Next()
return vertices
def face_normal(face: TopoDS_Face) -> gp_Dir:
"""
:param face:
:return:
"""
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 make_coons(edges):
bt = BRep_Tool()
if len(edges) == 4:
spl1, spl2, spl3, spl4 = edges #[curve_to_bspline(bt.Curve(i)[0]) for i in edges]
srf = GeomFill_BSplineCurves(spl1, spl2, spl3, spl4,
GeomFill_StretchStyle)
elif len(edges) == 3:
spl1, spl2, spl3 = edges #[curve_to_bspline(bt.Curve(i)[0]) for i in edges]
srf = GeomFill_BSplineCurves(spl1, spl2, spl3, GeomFill_StretchStyle)
elif len(edges) == 2:
spl1, spl2 = edges #[curve_to_bspline(bt.Curve(i)[0]) for i in edges]
srf = GeomFill_BSplineCurves(spl1, spl2, GeomFill_StretchStyle)
else:
raise ValueError('give 2,3 or 4 curves')
return srf.Surface()
def continuity_edge_face(self, edge, face):
"""
compute the continuity between two faces at :edge:
:param edge: an Edge or TopoDS_Edge from :face:
:param face: a Face or TopoDS_Face
:return: bool, GeomAbs_Shape if it has continuity, otherwise
False, None
"""
bt = BRep_Tool()
if bt.HasContinuity(edge, self, face):
continuity = bt.Continuity(edge, self, face)
return True, continuity
else:
return False, None
def __init__(self, pnt):
if isinstance(pnt, (list, tuple)):
gp_Pnt.__init__(self, *pnt)
elif isinstance(pnt, vec):
gp_Pnt.__init__(self, *pnt)
elif isinstance(pnt, gp_Pnt):
gp_Pnt.__init__(self, pnt)
elif isinstance(pnt, TopoDS_Vertex):
# convert to type "gp_Pnt"
gp_Pnt.__init__(self, BRep_Tool.Pnt(pnt))
elif isinstance(pnt, TopoDS_Shape):
self.brt = BRep_Tool()
self.pnt1 = self.brt.Pnt(topods_Vertex(pnt))
gp_Pnt.__init__(self, self.pnt1.XYZ())
else:
raise TypeError
def format_wire_for_roboDK(wire, is_reverse=False):
vertices = sweeper.get_ordered_vertices_from_wire(wire)
brt = BRep_Tool()
wire = []
last_path_direction = None
for i in range(len(vertices)):
index = i
next_index = index + 1
if is_reverse:
index = len(vertices) - 1 - i
next_index = index - 1
v = vertices[index]
pnt = brt.Pnt(topods_Vertex(v))
normal = get_vertex_normal(v, front_face)
if not ((index == 0 and is_reverse) or
(index == len(vertices) - 1 and not is_reverse)):
pnt_next = brt.Pnt(topods_Vertex(vertices[next_index]))
mat_pnt = numpy.mat([pnt.X(), pnt.Y(), pnt.Z()])
mat_pnt_next = numpy.mat(
[pnt_next.X(), pnt_next.Y(),
pnt_next.Z()])
path_direction = mat_pnt_next - mat_pnt
path_direction = path_direction / scipy.linalg.norm(path_direction)
last_path_direction = path_direction
else:
path_direction = last_path_direction
#direction should be away from base_position
p1 = [pnt.X() + normal.X(), pnt.Y() + normal.Y(), pnt.Z() + normal.Z()]
p2 = [pnt.X() - normal.X(), pnt.Y() - normal.Y(), pnt.Z() - normal.Z()]
#normal vector should point towards base_position
if sweeper.get_distance_points(
p1, sweeper.base_position) < sweeper.get_distance_points(
p2, sweeper.base_position):
direction = [normal.X(), normal.Y(), normal.Z()]
else:
direction = [-normal.X(), -normal.Y(), -normal.Z()]
wire.append({
"location": [pnt.X(), pnt.Y(), pnt.Z()],
"direction":
direction,
"path_direction": [
path_direction.item(0),
path_direction.item(1),
path_direction.item(2)
]
})
return wire
def GetFacesSurfaces(BRepShape):
FaceExplorer = TopExp_Explorer(BRepShape, TopAbs_FACE)
Faces = []
while FaceExplorer.More():
ShapeFace = FaceExplorer.Current() # a TopoDS_Shape
# Convert TopoDS_Shape to a TopoDS_Face
Face = topods.Face(ShapeFace)
Faces.append(Face)
FaceExplorer.Next()
pass
Surfaces = [BRep_Tool().Surface(Face) for Face in Faces]
SurfObjs = [Surface.GetObject() for Surface in Surfaces]
return (Faces, Surfaces, SurfObjs)
def dumpTopology(shape, level=0):
"""
Print the details of an object from the top down
"""
brt = BRep_Tool()
s = shape.ShapeType()
if s == TopAbs_VERTEX:
pnt = brt.Pnt(topods_Vertex(shape))
print(".." * level + "<Vertex %i: %s %s %s>" % (hash(shape), pnt.X(), pnt.Y(), pnt.Z()))
else:
print(".." * level, end="")
print(shapeTypeString(shape))
it = TopoDS_Iterator(shape)
while it.More():
shp = it.Value()
it.Next()
dumpTopology(shp, level + 1)
def continuity_edge_face(self, edge, face):
"""
compute the continuity between two faces at :edge:
:param edge: an Edge or TopoDS_Edge from :face:
:param face: a Face or TopoDS_Face
:return: bool, GeomAbs_Shape if it has continuity, otherwise
False, None
"""
edge = edge if not isinstance(edge,KbeObject) else edge.topo
face = face if not isinstance(face, KbeObject) else face.topo
bt = BRep_Tool()
if bt.HasContinuity(edge, self.topo, face):
continuity = bt.Continuity(edge, self.topo, face)
return True, continuity
else:
return False, None
def __init__(self, wireA, wireB):
self.wireA = wireA
self.wireB = wireB
self.we_A = WireExplorer(self.wireA)
self.we_B = WireExplorer(self.wireB)
self.tp_A = Topo(self.wireA)
self.tp_B = Topo(self.wireB)
self.bt = BRep_Tool()
self.vertsA = [v for v in self.we_A.ordered_vertices()]
self.vertsB = [v for v in self.we_B.ordered_vertices()]
self.edgesA = [v for v in WireExplorer(wireA).ordered_edges()]
self.edgesB = [v for v in WireExplorer(wireB).ordered_edges()]
self.pntsB = [self.bt.Pnt(v) for v in self.vertsB]
self.number_of_vertices = len(self.vertsA)
self.index = 0
def dump_topology_to_string(shape, level=0, buffer=""):
"""
Reutnrs the details of an object from the top down
"""
brt = BRep_Tool()
s = shape.ShapeType()
if s == TopAbs_VERTEX:
pnt = brt.Pnt(topods_Vertex(shape))
print(".." * level + "<Vertex %i: %s %s %s>\n" %
(hash(shape), pnt.X(), pnt.Y(), pnt.Z()))
else:
print(".." * level, end="")
print(shape_type_string(shape))
it = TopoDS_Iterator(shape)
while it.More() and level < 5: # LEVEL MAX
shp = it.Value()
it.Next()
print(dump_topology_to_string(shp, level + 1, buffer))
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 make_point(vertex):
#print "make_point: vertex=", vertex
if isinstance(vertex, TopoDS_Vertex):
#first check to see if it points anywhere
location = vertex.Location()
if location.IsDifferent(location.__class__()) == 1:
print "making a gp_Pnt"
pnt = BRep_Tool().Pnt(vertex)
print "making a point"
return Point(pnt)
else:
print "vertex wasn't anything special"
return Point(0, 0, 0) #but it might not actually be 0,0,0
elif isinstance(vertex, Point):
return vertex
elif isinstance(vertex, gp_Pnt):
return Point(vertex)
else:
return vertex
def simple_mesh():
#
# Create the shape
#
shape = BRepPrimAPI_MakeBox(200, 200, 200).Shape()
theBox = BRepPrimAPI_MakeBox(200, 60, 60).Shape()
theSphere = BRepPrimAPI_MakeSphere(gp_Pnt(100, 20, 20), 80).Shape()
shape = BRepAlgoAPI_Fuse(theSphere, theBox).Shape()
#
# Mesh the shape
#
BRepMesh_IncrementalMesh(shape, 0.8)
builder = BRep_Builder()
comp = TopoDS_Compound()
builder.MakeCompound(comp)
bt = BRep_Tool()
ex = TopExp_Explorer(shape, TopAbs_FACE)
while ex.More():
face = topods_Face(ex.Current())
location = TopLoc_Location()
facing = (bt.Triangulation(face, location)).GetObject()
tab = facing.Nodes()
tri = facing.Triangles()
for i in range(1, facing.NbTriangles()+1):
trian = tri.Value(i)
index1, index2, index3 = trian.Get()
for j in range(1, 4):
if j == 1:
m = index1
n = index2
elif j == 2:
n = index3
elif j == 3:
m = index2
me = BRepBuilderAPI_MakeEdge(tab.Value(m), tab.Value(n))
if me.IsDone():
builder.Add(comp, me.Edge())
ex.Next()
display.EraseAll()
display.DisplayShape(shape)
display.DisplayShape(comp, update=True)
def DumpTop(self, shape, level=0):
"""
Print the details of an object from the top down
"""
brt = BRep_Tool()
s = shape.ShapeType()
if s == TopAbs_VERTEX:
pnt = brt.Pnt(topods_Vertex(shape))
dmp = " " * level
dmp += "%s - " % shapeTypeString(shape)
dmp += "%.5e %.5e %.5e" % (pnt.X(), pnt.Y(), pnt.Z())
print(dmp)
else:
dmp = " " * level
dmp += shapeTypeString(shape)
print(dmp)
it = TopoDS_Iterator(shape)
while it.More():
shp = it.Value()
it.Next()
self.DumpTop(shp, level + 1)
def discretize(shape, tol):
"""This method discretizes the OpenCascade shape.
:param shape: Shape to discretize
:type shape:
:return: discretized face; profile coordinates; id of the surface the\
coordinates belong to
:rtype: OCC.TopoDS.TopoDS_Compound; numpy.ndarray; numpy.ndarray
"""
BRepMesh_IncrementalMesh(shape, tol, False, 5)
builder = BRep_Builder()
comp = TopoDS_Compound()
builder.MakeCompound(comp)
bt = BRep_Tool()
ex = TopExp_Explorer(shape, TopAbs_EDGE)
edge_coords = np.zeros([0, 3])
edge_ids = np.zeros([0], dtype=int)
edge_id = 0
while ex.More():
edge = topods_Edge(ex.Current())
location = TopLoc_Location()
edging = (bt.Polygon3D(edge, location)).GetObject()
tab = edging.Nodes()
for i in range(1, edging.NbNodes() + 1):
p = tab.Value(i)
edge_coords = np.append(edge_coords,
[[p.X(), p.Y(), p.Z()]],
axis=0)
edge_ids = np.append(edge_ids, edge_id)
mv = BRepBuilderAPI_MakeVertex(p)
if mv.IsDone():
builder.Add(comp, mv.Vertex())
edge_id += 1
ex.Next()
edge_coords = np.round(edge_coords, 8)
return edge_coords, edge_ids
def arrange_edges_2_wires(occedgelist, isclosed=False):
from OCC.TopoDS import topods
from OCC.TopExp import topexp
from OCC.BRep import BRep_Tool
from OCC.ShapeAnalysis import ShapeAnalysis_WireOrder
from OCC.Precision import precision
from OCC.BRepBuilderAPI import BRepBuilderAPI_WireDone, BRepBuilderAPI_EmptyWire, BRepBuilderAPI_DisconnectedWire, BRepBuilderAPI_NonManifoldWire
wb_errdict = {
BRepBuilderAPI_WireDone: "No error",
BRepBuilderAPI_EmptyWire: "Empty wire",
BRepBuilderAPI_DisconnectedWire: "disconnected wire",
BRepBuilderAPI_NonManifoldWire: "non-manifold wire"
}
sawo_statusdict = {
0: "all edges are direct and in sequence",
1: "all edges are direct but some are not in sequence",
2: "unresolved gaps remain",
-1: "some edges are reversed, but no gaps remain",
-2: "some edges are reversed and some gaps remain",
-10: "failure on reorder"
}
mode3d = True
SAWO = ShapeAnalysis_WireOrder(mode3d, precision.PConfusion())
for edge in occedgelist:
V1 = topexp.FirstVertex(topods.Edge(edge))
V2 = topexp.LastVertex(topods.Edge(edge))
pnt1 = BRep_Tool().Pnt(V1)
pnt2 = BRep_Tool().Pnt(V2)
SAWO.Add(pnt1.XYZ(), pnt2.XYZ())
SAWO.SetKeepLoopsMode(True)
SAWO.Perform(isclosed)
#print "SAWO.Status()", SAWO.Status()
if not SAWO.IsDone():
raise RuntimeError, "build wire: Unable to reorder edges: \n" + sawo_statusdict[
SAWO.Status()]
else:
if SAWO.Status() not in [0, -1]:
pass # not critical, wirebuilder will handle this
SAWO.SetChains(precision.PConfusion())
wirelist = []
#print "Number of chains: ", SAWO.NbChains()
for i in range(SAWO.NbChains()):
wirebuilder = BRepBuilderAPI_MakeWire()
estart, eend = SAWO.Chain(i + 1)
#print "Number of edges in chain", i, ": ", eend - estart + 1
if (eend - estart + 1) == 0:
continue
for j in range(estart, eend + 1):
idx = abs(
SAWO.Ordered(j)
) # wirebuilder = s_addToWireBuilder(wirebuilder, edgelist[idx-1])
edge2w = occedgelist[idx - 1]
wirebuilder.Add(edge2w)
if wirebuilder is None:
raise RuntimeError, " build wire: Error adding edge number " + str(
j + 1) + " to Wire number " + str(i)
err = wirebuilder.Error()
if err != BRepBuilderAPI_WireDone:
raise RuntimeError, "Overlay2D: build wire: Error adding edge number " + str(
j + 1) + " to Wire number " + str(
i) + ": \n" + wb_errdict[err]
try:
wirebuilder.Build()
aWire = wirebuilder.Wire()
wirelist.append(aWire)
except Exception, err:
raise RuntimeError, "Overlay2D: build wire: Creation of Wire number " + str(
i) + " from edge(s) failed. \n" + str(err)
wirebuilder.Build()
aWire = wirebuilder.Wire()
wirelist.append(aWire)
#!/usr/bin/env python
def shape_to_pts(sh):
return [BRep_Tool().Pnt(topods_Vertex(v)) for v in Topo(sh).vertices()]
def __init__(self, shape):
from OCC.BRep import BRep_Tool
from OCC.BRepMesh import BRepMesh_IncrementalMesh
from OCC.TopAbs import TopAbs_FACE, TopAbs_VERTEX
from OCC.TopExp import TopExp_Explorer
from OCC.TopLoc import TopLoc_Location
from OCC.TopoDS import topods_Face, topods_Vertex, TopoDS_Iterator
vertices = [] # a (nested) list of vec3
triangles = [] # a (flat) list of integers
normals = []
uv = []
# Mesh the shape
linDeflection = 0.8
BRepMesh_IncrementalMesh(shape, linDeflection)
bt = BRep_Tool()
# Explore the faces of the shape
# each face is triangulated, we need to collect all the parts
expFac = TopExp_Explorer(shape, TopAbs_FACE)
while expFac.More():
face = topods_Face(expFac.Current())
location = TopLoc_Location()
facing = (bt.Triangulation(face, location)).GetObject()
try:
tri = facing.Triangles()
nTri = facing.NbTriangles()
ver = facing.Nodes()
except:
tri = None
nTri = None
ver = None
# store origin of the face's local coordinates
transf = face.Location().Transformation()
# iterate over triangles and store indices of vertices defining each triangle
# OCC uses one-based indexing
for i in range(1, nTri + 1):
# each triangle is defined by three points
# each point is defined by its index in the list of vertices
index1, index2, index3 = tri.Value(i).Get()
indices = [index1, index2, index3]
# python uses zero-based indexing
# for each vertex of a triangle, check whether it is already known
# then store it (or not) and update the index
for idx in [0, 1, 2]:
# read global coordinates of each point
vec3 = [
ver.Value(indices[idx]).Transformed(transf).X(),
ver.Value(indices[idx]).Transformed(transf).Y(),
ver.Value(indices[idx]).Transformed(transf).Z()
]
if vec3 not in vertices:
vertices.append(vec3)
indices[idx] = vertices.index(vec3)
triangles.extend(indices)
expFac.Next()
self.shape = shape
self.vertices = vertices
self.triangles = triangles
self.normals = normals
self.uv = uv