Polyline¶

The POLYLINE entity (POLYLINE DXF Reference) is very complex, it’s used to build 2D/3D polylines, 3D meshes and 3D polyfaces. For every type exists a different wrapper class but they all have the same DXF type “POLYLINE”. Detect the actual POLYLINE type by the method Polyline.get_mode().

POLYLINE types returned by Polyline.get_mode():

'AcDb2dPolyline' for 2D Polyline

'AcDb3dPolyline' for 3D Polyline

'AcDbPolygonMesh' for Polymesh

'AcDbPolyFaceMesh' for Polyface

For 2D entities all vertices in OCS.

For 3D entities all vertices in WCS.

Subclass of	`ezdxf.entities.DXFGraphic`
DXF type	`'POLYLINE'`
2D factory function	`ezdxf.layouts.BaseLayout.add_polyline2d()`
3D factory function	`ezdxf.layouts.BaseLayout.add_polyline3d()`
Inherited DXF attributes	Common graphical DXF attributes

Warning

Do not instantiate entity classes by yourself - always use the provided factory functions!

class ezdxf.entities.Polyline¶

The Vertex entities are stored in the Python list Polyline.vertices. The VERTEX entities can be retrieved and deleted by direct access to the Polyline.vertices attribute:

# delete first and second vertex
del polyline.vertices[:2]

dxf.elevation¶: Elevation point, the X and Y values are always 0, and the Z value is the polyline elevation (3D Point).

dxf.flags¶

Constants defined in ezdxf.lldxf.const:

`Polyline.dxf.flags`	Value	Description
POLYLINE_CLOSED	1	This is a closed Polyline (or a polygon mesh closed in the M direction)
POLYLINE_MESH_CLOSED_M_DIRECTION	1	equals POLYLINE_CLOSED
POLYLINE_CURVE_FIT_VERTICES_ADDED	2	Curve-fit vertices have been added
POLYLINE_SPLINE_FIT_VERTICES_ADDED	4	Spline-fit vertices have been added
POLYLINE_3D_POLYLINE	8	This is a 3D Polyline
POLYLINE_3D_POLYMESH	16	This is a 3D polygon mesh
POLYLINE_MESH_CLOSED_N_DIRECTION	32	The polygon mesh is closed in the N direction
POLYLINE_POLYFACE_MESH	64	This Polyline is a polyface mesh
POLYLINE_GENERATE_LINETYPE_PATTERN	128	The linetype pattern is generated continuously around the vertices of this Polyline

dxf.default_start_width¶: Default line start width (float); default is 0

dxf.default_end_width¶: Default line end width (float); default is 0

dxf.m_count¶: Polymesh M vertex count (int); default is 1

dxf.n_count¶: Polymesh N vertex count (int); default is 1

dxf.m_smooth_density¶: Smooth surface M density (int); default is 0

dxf.n_smooth_density¶: Smooth surface N density (int); default is 0

dxf.smooth_type¶

Curves and smooth surface type (int); default is 0, see table below

Constants for smooth_type defined in ezdxf.lldxf.const:

`Polyline.dxf.smooth_type`	Value	Description
POLYMESH_NO_SMOOTH	0	no smooth surface fitted
POLYMESH_QUADRATIC_BSPLINE	5	quadratic B-spline surface
POLYMESH_CUBIC_BSPLINE	6	cubic B-spline surface
POLYMESH_BEZIER_SURFACE	8	Bezier surface

vertices¶: List of Vertex entities.

is_2d_polyline¶: True if POLYLINE is a 2D polyline.

is_3d_polyline¶: True if POLYLINE is a 3D polyline.

is_polygon_mesh¶: True if POLYLINE is a polygon mesh, see Polymesh

is_poly_face_mesh¶: True if POLYLINE is a poly face mesh, see Polyface

is_closed¶: True if POLYLINE is closed.

is_m_closed¶: True if POLYLINE (as Polymesh) is closed in m direction.

is_n_closed¶: True if POLYLINE (as Polymesh) is closed in n direction.

has_arc¶: Returns True if 2D POLYLINE has an arc segment.

has_width¶: Returns True if 2D POLYLINE has default width values or any segment with width attributes.

get_mode() → str¶

Returns POLYLINE type as string:

“AcDb2dPolyline”
“AcDb3dPolyline”
“AcDbPolygonMesh”
“AcDbPolyFaceMesh”

m_close(status=True) → None¶: Close POLYMESH in m direction if status is True (also closes POLYLINE), clears closed state if status is False.

n_close(status=True) → None¶: Close POLYMESH in n direction if status is True, clears closed state if status is False.

close(m_close=True, n_close=False) → None¶: Set closed state of POLYMESH and POLYLINE in m direction and n direction. True set closed flag, False clears closed flag.

__len__() → int¶: Returns count of Vertex entities.

__getitem__(pos) → DXFVertex¶: Get Vertex entity at position pos, supports list-like slicing.

points() → Iterator[Vec3]¶: Returns iterable of all polyline vertices as (x, y, z) tuples, not as Vertex objects.

append_vertex(point: UVec, dxfattribs=None) → None¶

Append a single Vertex entity at location point.

Parameters:

point – as (x, y[, z]) tuple
dxfattribs – dict of DXF attributes for Vertex class

append_vertices(points: Iterable[UVec], dxfattribs=None) → None¶

Append multiple Vertex entities at location points.

Parameters:

points – iterable of (x, y[, z]) tuples
dxfattribs – dict of DXF attributes for the VERTEX objects

append_formatted_vertices(points: Iterable[UVec], format: str = 'xy', dxfattribs=None) → None¶

Append multiple Vertex entities at location points.

Parameters:

points – iterable of (x, y, [start_width, [end_width, [bulge]]]) tuple
format – format string, default is “xy”, see: User Defined Point Format Codes
dxfattribs – dict of DXF attributes for the VERTEX objects

insert_vertices(pos: int, points: Iterable[UVec], dxfattribs=None) → None¶

Insert vertices points into Polyline.vertices list at insertion location pos .

Parameters:

pos – insertion position of list Polyline.vertices
points – list of (x, y[, z]) tuples
dxfattribs – dict of DXF attributes for Vertex class

transform(m: Matrix44) → Polyline¶

Transform the POLYLINE entity by transformation matrix m inplace.

A non-uniform scaling is not supported if a 2D POLYLINE contains circular arc segments (bulges).

Parameters:: m – transformation Matrix44
Raises:: NonUniformScalingError – for non-uniform scaling of 2D POLYLINE containing circular arc segments (bulges)

virtual_entities() → Iterator[Line | Arc | Face3d]¶

Yields the graphical representation of POLYLINE as virtual DXF primitives (LINE, ARC or 3DFACE).

These virtual entities are located at the original location, but are not stored in the entity database, have no handle and are not assigned to any layout.

explode(target_layout: BaseLayout | None = None) → EntityQuery¶

Explode the POLYLINE entity as DXF primitives (LINE, ARC or 3DFACE) into the target layout, if the target layout is None, the target layout is the layout of the POLYLINE entity.

Returns an EntityQuery container referencing all DXF primitives.

Parameters:: target_layout – target layout for DXF primitives, None for same layout as source entity.

Vertex¶

A VERTEX (VERTEX DXF Reference) represents a polyline/mesh vertex.

Subclass of	`ezdxf.entities.DXFGraphic`
DXF type	`'VERTEX'`
Factory function	`Polyline.append_vertex()`
Factory function	`Polyline.extend()`
Factory function	`Polyline.insert_vertices()`
Inherited DXF Attributes	Common graphical DXF attributes

class ezdxf.entities.Vertex¶

dxf.location¶: Vertex location (2D/3D Point OCS when 2D, WCS when 3D)

dxf.start_width¶: Line segment start width (float); default is 0

dxf.end_width¶: Line segment end width (float); default is 0

dxf.bulge¶

Bulge value (float); default is 0.

The bulge value is used to create arc shaped line segments.

dxf.flags¶

Constants defined in ezdxf.lldxf.const:

Vertex.dxf.flags	Value	Description
VTX_EXTRA_VERTEX_CREATED	1	Extra vertex created by curve-fitting
VTX_CURVE_FIT_TANGENT	2	curve-fit tangent defined for this vertex. A curve-fit tangent direction of 0 may be omitted from the DXF output, but is significant if this bit is set.
VTX_SPLINE_VERTEX_CREATED	8	spline vertex created by spline-fitting
VTX_SPLINE_FRAME_CONTROL_POINT	16	spline frame control point
VTX_3D_POLYLINE_VERTEX	32	3D polyline vertex
VTX_3D_POLYGON_MESH_VERTEX	64	3D polygon mesh
VTX_3D_POLYFACE_MESH_VERTEX	128	polyface mesh vertex

dxf.tangent¶: Curve fit tangent direction (float), used for 2D spline in DXF R12.

dxf.vtx1¶: Index of 1st vertex, if used as face (feature for experts)

dxf.vtx2¶: Index of 2nd vertex, if used as face (feature for experts)

dxf.vtx3¶: Index of 3rd vertex, if used as face (feature for experts)

dxf.vtx4¶: Index of 4th vertex, if used as face (feature for experts)

is_2d_polyline_vertex¶

is_3d_polyline_vertex¶

is_polygon_mesh_vertex¶

is_poly_face_mesh_vertex¶

is_face_record¶

format(format='xyz') → Sequence¶

Return formatted vertex components as tuple.

Format codes:

“x” = x-coordinate

“y” = y-coordinate

“z” = z-coordinate

“s” = start width

“e” = end width

“b” = bulge value

“v” = (x, y, z) as tuple

Args:: format: format string, default is “xyz”

Polymesh¶

Subclass of	`ezdxf.entities.Polyline`
DXF type	`'POLYLINE'`
Factory function	`ezdxf.layouts.BaseLayout.add_polymesh()`
Inherited DXF Attributes	Common graphical DXF attributes

class ezdxf.entities.Polymesh¶

A polymesh is a grid of m_count by n_count vertices, every vertex has its own (x, y, z) location. The Polymesh is a subclass of Polyline, the DXF type is also “POLYLINE”, the method get_mode() returns “AcDbPolygonMesh”.

get_mesh_vertex(pos: tuple[int, int]) → DXFVertex¶

Get location of a single mesh vertex.

Parameters:: pos – 0-based (row, col) tuple, position of mesh vertex

set_mesh_vertex(pos: tuple[int, int], point: UVec, dxfattribs=None)¶

Set location and DXF attributes of a single mesh vertex.

Parameters:

pos – 0-based (row, col) tuple, position of mesh vertex
point – (x, y, z) tuple, new 3D coordinates of the mesh vertex
dxfattribs – dict of DXF attributes

get_mesh_vertex_cache() → MeshVertexCache¶: Get a MeshVertexCache object for this POLYMESH. The caching object provides fast access to the location attribute of mesh vertices.

MeshVertexCache¶

class ezdxf.entities.MeshVertexCache¶

Cache mesh vertices in a dict, keys are 0-based (row, col) tuples.

Set vertex location: cache[row, col] = (x, y, z)

Get vertex location: x, y, z = cache[row, col]

vertices¶: Dict of mesh vertices, keys are 0-based (row, col) tuples.

__getitem__(pos: tuple[int, int]) → UVec¶

Get mesh vertex location as (x, y, z)-tuple.

Parameters:: pos – 0-based (row, col)-tuple.

__setitem__(pos: tuple[int, int], location: UVec) → None¶

Get mesh vertex location as (x, y, z)-tuple.

Parameters:

pos – 0-based (row, col)-tuple.
location – (x, y, z)-tuple

Polyface¶

Subclass of	`ezdxf.entities.Polyline`
DXF type	`'POLYLINE'`
Factory function	`ezdxf.layouts.BaseLayout.add_polyface()`
Inherited DXF Attributes	Common graphical DXF attributes