'jdZddlmZddlmZmZmZddlmZddl m Z m Z m Z m Z mZer ddlmZddlmZGdd Zd S) a DXF R12 Splines =============== DXF R12 supports 2d B-splines, but Autodesk do not document the usage in the DXF Reference. The base entity for splines in DXF R12 is the POLYLINE entity. Transformed Into 3D Space ------------------------- The spline itself is always in a plane, but as any 2D entity, the spline can be transformed into the 3D object by elevation, extrusion and thickness/width. Open Quadratic Spline with Fit Vertices ------------------------------------- Example: 2D_SPLINE_QUADRATIC.dxf expected knot vector: open uniform degree: 2 order: 3 POLYLINE: flags (70): 4 = SPLINE_FIT_VERTICES_ADDED smooth type (75): 5 = QUADRATIC_BSPLINE Sequence of VERTEX flags (70): SPLINE_VERTEX_CREATED = 8 # Spline vertex created by spline-fitting This vertices are the curve vertices of the spline (fitted). Frame control vertices appear after the curve vertices. Sequence of VERTEX flags (70): SPLINE_FRAME_CONTROL_POINT = 16 No control point at the starting point, but a control point at the end point, last control point == last fit vertex Closed Quadratic Spline with Fit Vertices ----------------------------------------- Example: 2D_SPLINE_QUADRATIC_CLOSED.dxf expected knot vector: closed uniform degree: 2 order: 3 POLYLINE: flags (70): 5 = CLOSED | SPLINE_FIT_VERTICES_ADDED smooth type (75): 5 = QUADRATIC_BSPLINE Sequence of VERTEX flags (70): SPLINE_VERTEX_CREATED = 8 # Spline vertex created by spline-fitting Frame control vertices appear after the curve vertices. Sequence of VERTEX flags (70): SPLINE_FRAME_CONTROL_POINT = 16 Open Cubic Spline with Fit Vertices ----------------------------------- Example: 2D_SPLINE_CUBIC.dxf expected knot vector: open uniform degree: 3 order: 4 POLYLINE: flags (70): 4 = SPLINE_FIT_VERTICES_ADDED smooth type (75): 6 = CUBIC_BSPLINE Sequence of VERTEX flags (70): SPLINE_VERTEX_CREATED = 8 # Spline vertex created by spline-fitting This vertices are the curve vertices of the spline (fitted). Frame control vertices appear after the curve vertices. Sequence of VERTEX flags (70): SPLINE_FRAME_CONTROL_POINT = 16 No control point at the starting point, but a control point at the end point, last control point == last fit vertex Closed Curve With Extra Vertices Created ---------------------------------------- Example: 2D_FIT_CURVE_CLOSED.dxf POLYLINE: flags (70): 3 = CLOSED | CURVE_FIT_VERTICES_ADDED Vertices with bulge values: flags (70): 1 = EXTRA_VERTEX_CREATED Vertex 70=0, Vertex 70=1, Vertex 70=0, Vertex 70=1 ) annotations) TYPE_CHECKINGIterableOptional)const)BSplineclosed_uniform_bsplineVec3UCSUVec) BaseLayout)Polylinec<eZdZdZ ddd Z dddZ dddZd S) R12SplineaDXF R12 supports 2D B-splines, but Autodesk do not document the usage in the DXF Reference. The base entity for splines in DXF R12 is the POLYLINE entity. The spline itself is always in a plane, but as any 2D entity, the spline can be transformed into the 3D object by elevation and extrusion (:ref:`OCS`, :ref:`UCS`). This way it was possible to store the spline parameters in the DXF R12 file, to allow CAD applications to modify the spline parameters and rerender the B-spline afterward again as polyline approximation. Therefore, the result is not better than an approximation by the :class:`Spline` class, it is also just a POLYLINE entity, but maybe someone need exact this tool in the future. Tcontrol_pointsIterable[UVec]degreeintclosedboolcTtj||_||_||_dS)z Args: control_points: B-spline control frame vertices degree: degree of B-spline, only 2 and 3 is supported closed: ``True`` for closed curve N)r listrrr)selfrrrs P/DATA/AppData/hermes/venv/lib/python3.11/site-packages/ezdxf/render/r12spline.py__init__zR12Spline.__init__s(#i77  (Nsegmentsucs Optional[UCS]return list[UVec]c|jrt|j|jdz}nt |j|jdz}||}fd|D}t |S)alApproximate the B-spline by a polyline with `segments` line segments. If `ucs` is not ``None``, ucs defines an :class:`~ezdxf.math.UCS`, to transform the curve into :ref:`OCS`. The control points are placed xy-plane of the UCS, don't use z-axis coordinates, if so make sure all control points are in a plane parallel to the OCS base plane (UCS xy-plane), else the result is unpredictable and depends on the CAD application used to open the DXF file - it may crash. Args: segments: count of line segments for approximation, vertex count is `segments` + 1 ucs: :class:`~ezdxf.math.UCS` definition, control points in ucs coordinates Returns: list of vertices in :class:`~ezdxf.math.OCS` as :class:`~ezdxf.math.Vec3` objects )orderNc3BK|]}|VdS)N)to_ocs).0vertexr s r z(R12Spline.approximate..s/BBv 6**BBBBBBr)rr rrr approximater)rrr splineverticess ` rr,zR12Spline.approximates, ; I+#4;?FFT0 aHHHF%%h// ?BBBBBBBHH~~rlayoutr rc|g|}|j}|jr ||jz}||j_|jdkr|j}n"|jdkr|j}ntd||j_ ||j |j_ | ||||jjt jd|j}|rSsaaD#"""""4444444444GGGGGGGGGGGGGG(((((((''''''}}}}}}}}}}r