def is_not_null_vector(v) -> bool:
return not NULLVEC.isclose(v)
def from_hatch_edge_path(cls,
edges: 'EdgePath',
ocs: OCS = None,
elevation: float = 0) -> 'Path':
"""
Returns a :class:`Path` from a :class:`~ezdxf.entities.Hatch` edge path.
"""
def add_line_edge(edge):
start = wcs(edge.start)
end = wcs(edge.end)
if len(path):
if path.end.isclose(start):
# path-end -> line-end
path.line_to(end)
elif path.end.isclose(end):
# path-end (==line-end) -> line-start
path.line_to(start)
else:
# path-end -> edge-start -> edge-end
path.line_to(start)
path.line_to(end)
else: # start path
path.start = start
path.line_to(end)
def add_arc_edge(edge):
x, y, *_ = edge.center
# from_arc() requires OCS data:
ellipse = ConstructionEllipse.from_arc(
center=(x, y, elevation),
radius=edge.radius,
extrusion=extrusion,
start_angle=edge.start_angle,
end_angle=edge.end_angle,
)
path.add_ellipse(ellipse, reset=not bool(path))
def add_ellipse_edge(edge):
ocs_ellipse = edge.construction_tool()
# ConstructionEllipse has WCS representation:
ellipse = ConstructionEllipse(
center=wcs(ocs_ellipse.center.replace(z=elevation)),
major_axis=wcs(ocs_ellipse.major_axis),
ratio=ocs_ellipse.ratio,
extrusion=extrusion,
start_param=ocs_ellipse.start_param,
end_param=ocs_ellipse.end_param,
)
path.add_ellipse(ellipse, reset=not bool(path))
def add_spline_edge(edge):
control_points = [wcs(p) for p in edge.control_points]
if len(control_points) == 0:
fit_points = [wcs(p) for p in edge.fit_points]
if len(fit_points):
bspline = from_fit_points(edge, fit_points)
else:
# No control points and no fit points:
# DXF structure error
return
else:
bspline = from_control_points(edge, control_points)
path.add_spline(bspline, reset=not bool(path))
def from_fit_points(edge, fit_points):
tangents = None
if edge.start_tangent and edge.end_tangent:
tangents = (wcs(edge.start_tangent), wcs(edge.end_tangent))
return global_bspline_interpolation(
fit_points,
degree=edge.degree,
tangents=tangents,
)
def from_control_points(edge, control_points):
return BSpline(control_points=control_points,
order=edge.degree + 1,
knots=edge.knot_values,
weights=edge.weights if edge.weights else None)
def wcs(vertex):
if ocs and ocs.transform:
return ocs.to_wcs((vertex.x, vertex.y, elevation))
else:
return Vector(vertex)
extrusion = ocs.uz if ocs else Z_AXIS
path = Path()
for edge in edges:
if edge.EDGE_TYPE == "LineEdge":
add_line_edge(edge)
elif edge.EDGE_TYPE == "ArcEdge":
if not math.isclose(edge.radius, 0):
add_arc_edge(edge)
elif edge.EDGE_TYPE == "EllipseEdge":
if not NULLVEC.isclose(edge.major_axis):
add_ellipse_edge(edge)
elif edge.EDGE_TYPE == "SplineEdge":
add_spline_edge(edge)
return path