r12writer¶

The fast file/stream writer creates simple DXF R12 drawings with just an ENTITIES section. The HEADER, TABLES and BLOCKS sections are not present except FIXED-TABLES are written. Only LINE, CIRCLE, ARC, TEXT, POINT, SOLID, 3DFACE and POLYLINE entities are supported. FIXED-TABLES is a predefined TABLES section, which will be written, if the init argument fixed_tables of R12FastStreamWriter is True.

The R12FastStreamWriter writes the DXF entities as strings direct to the stream without creating an in-memory drawing and therefore the processing is very fast.

Because of the lack of a BLOCKS section, BLOCK/INSERT can not be used. Layers can be used, but this layers have a default setting color = 7 (black/white) and linetype = 'Continuous'. If writing the FIXED-TABLES, some predefined text styles and line types are available, else text style is always 'STANDARD' and line type is always 'ByLayer'.

If using FIXED-TABLES, following predefined line types are available:

CONTINUOUS
CENTER ____ _ ____ _ ____ _ ____ _ ____ _ ____
CENTERX2 ________ __ ________ __ ________
CENTER2 ____ _ ____ _ ____ _ ____ _ ____
DASHED __ __ __ __ __ __ __ __ __ __ __ __ __ _
DASHEDX2 ____ ____ ____ ____ ____ ____
DASHED2 _ _ _ _ _ _ _ _ _ _ _ _ _ _
PHANTOM ______ __ __ ______ __ __ ______
PHANTOMX2 ____________ ____ ____ ____________
PHANTOM2 ___ _ _ ___ _ _ ___ _ _ ___ _ _ ___
DASHDOT __ . __ . __ . __ . __ . __ . __ . __
DASHDOTX2 ____ . ____ . ____ . ____
DASHDOT2 _ . _ . _ . _ . _ . _ . _ . _
DOT . . . . . . . . . . . . . . . .
DOTX2 . . . . . . . .
DOT2 . . . . . . . . . . . . . . . . . . .
DIVIDE __ . . __ . . __ . . __ . . __ . . __
DIVIDEX2 ____ . . ____ . . ____ . . ____
DIVIDE2 _ . _ . _ . _ . _ . _ . _ . _

If using FIXED-TABLES, following predefined text styles are available:

OpenSans
OpenSansCondensed-Light

Tutorial¶

A simple example with different DXF entities:

from random import random
from ezdxf.addons import r12writer

with r12writer("quick_and_dirty_dxf_r12.dxf") as dxf:
    dxf.add_line((0, 0), (17, 23))
    dxf.add_circle((0, 0), radius=2)
    dxf.add_arc((0, 0), radius=3, start=0, end=175)
    dxf.add_solid([(0, 0), (1, 0), (0, 1), (1, 1)])
    dxf.add_point((1.5, 1.5))

    # 2d polyline, new in v0.12
    dxf.add_polyline_2d([(5, 5), (7, 3), (7, 6)])

    # 2d polyline with bulge value, new in v0.12
    dxf.add_polyline_2d([(5, 5), (7, 3, 0.5), (7, 6)], format='xyb')

    # 3d polyline only, changed in v0.12
    dxf.add_polyline([(4, 3, 2), (8, 5, 0), (2, 4, 9)])

    dxf.add_text("test the text entity", align="MIDDLE_CENTER")

A simple example of writing really many entities in a short time:

from random import random
from ezdxf.addons import r12writer

MAX_X_COORD = 1000.0
MAX_Y_COORD = 1000.0
CIRCLE_COUNT = 1000000

with r12writer("many_circles.dxf") as dxf:
    for i in range(CIRCLE_COUNT):
        dxf.add_circle((MAX_X_COORD*random(), MAX_Y_COORD*random()), radius=2)

Show all available line types:

import ezdxf

LINETYPES = [
    'CONTINUOUS', 'CENTER', 'CENTERX2', 'CENTER2',
    'DASHED', 'DASHEDX2', 'DASHED2', 'PHANTOM', 'PHANTOMX2',
    'PHANTOM2', 'DASHDOT', 'DASHDOTX2', 'DASHDOT2', 'DOT',
    'DOTX2', 'DOT2', 'DIVIDE', 'DIVIDEX2', 'DIVIDE2',
]

with r12writer('r12_linetypes.dxf', fixed_tables=True) as dxf:
    for n, ltype in enumerate(LINETYPES):
        dxf.add_line((0, n), (10, n), linetype=ltype)
        dxf.add_text(ltype, (0, n+0.1), height=0.25, style='OpenSansCondensed-Light')

Reference¶

ezdxf.addons.r12writer.r12writer(stream: TextIO | BinaryIO | str, fixed_tables=False, fmt='asc') → R12FastStreamWriter¶

Context manager for writing DXF entities to a stream/file. stream can be any file like object with a write() method or just a string for writing DXF entities to the file system. If fixed_tables is True, a standard TABLES section is written in front of the ENTITIES section and some predefined text styles and line types can be used.

Set argument fmt to “asc” to write ASCII DXF file (default) or “bin” to write Binary DXF files. ASCII DXF require a TextIO stream and Binary DXF require a BinaryIO stream.

class ezdxf.addons.r12writer.R12FastStreamWriter(stream: TextIO, fixed_tables=False)¶

Fast stream writer to create simple DXF R12 drawings.

Parameters:

stream – a file like object with a write() method.
fixed_tables – if fixed_tables is True, a standard TABLES section is written in front of the ENTITIES section and some predefined text styles and line types can be used.

close() → None¶: Writes the DXF tail. Call is not necessary when using the context manager r12writer().

add_line(start: Sequence[float], end: Sequence[float], layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a LINE entity from start to end.

Parameters:

start – start vertex as (x, y[, z]) tuple
end – end vertex as as (x, y[, z]) tuple
layer – layer name as string, without a layer definition the assigned color = 7 (black/white) and line type is 'Continuous'.
color – color as AutoCAD Color Index (ACI) in the range from 0 to 256, 0 is ByBlock and 256 is ByLayer, default is ByLayer which is always color = 7 (black/white) without a layer definition.
linetype – line type as string, if FIXED-TABLES are written some predefined line types are available, else line type is always ByLayer, which is always 'Continuous' without a LAYERS table.

add_circle(center: Sequence[float], radius: float, layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a CIRCLE entity.

Parameters:

center – circle center point as (x, y) tuple
radius – circle radius as float
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_arc(center: Sequence[float], radius: float, start: float = 0, end: float = 360, layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add an ARC entity. The arc goes counter-clockwise from start angle to end angle.

Parameters:

center – arc center point as (x, y) tuple
radius – arc radius as float
start – arc start angle in degrees as float
end – arc end angle in degrees as float
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_point(location: Sequence[float], layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a POINT entity.

Parameters:

location – point location as (x, y [,z]) tuple
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_3dface(vertices: Iterable[Sequence[float]], invisible: int = 0, layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a 3DFACE entity. 3DFACE is a spatial area with 3 or 4 vertices, all vertices have to be in the same plane.

Parameters:

vertices – iterable of 3 or 4 (x, y, z) vertices.
invisible –
bit coded flag to define the invisible edges,
1. edge = 1
2. edge = 2
3. edge = 4
4. edge = 8
Add edge values to set multiple edges invisible, 1. edge + 3. edge = 1 + 4 = 5, all edges = 15
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_solid(vertices: Iterable[Sequence[float]], layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a SOLID entity. SOLID is a solid filled area with 3 or 4 edges and SOLID is a 2D entity.

Parameters:

vertices – iterable of 3 or 4 (x, y[, z]) tuples, z-axis will be ignored.
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_polyline_2d(points: Iterable[Sequence], format: str = 'xy', closed: bool = False, start_width: float = 0, end_width: float = 0, layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a 2D POLYLINE entity with start width, end width and bulge value support.

Format codes:

x	x-coordinate
y	y-coordinate
s	start width
e	end width
b	bulge value
v	(x, y) tuple (z-axis is ignored)

Parameters:

points – iterable of (x, y, [start_width, [end_width, [bulge]]]) tuple, value order according to the format string, unset values default to 0
format – format: format string, default is 'xy'
closed – True creates a closed polyline
start_width – default start width, default is 0
end_width – default end width, default is 0
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_polyline(vertices: Iterable[Sequence[float]], closed: bool = False, layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a 3D POLYLINE entity.

Parameters:

vertices – iterable of (x, y[, z]) tuples, z-axis is 0 by default
closed – True creates a closed polyline
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_polyface(vertices: Iterable[Sequence[float]], faces: Iterable[Sequence[int]], layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a POLYFACE entity. The POLYFACE entity supports only faces of maximum 4 vertices, more indices will be ignored. A simple square would be:

v0 = (0, 0, 0)
v1 = (1, 0, 0)
v2 = (1, 1, 0)
v3 = (0, 1, 0)
dxf.add_polyface(vertices=[v0, v1, v2, v3], faces=[(0, 1, 2, 3)])

All 3D form functions of the ezdxf.render.forms module return MeshBuilder objects, which provide the required vertex and face lists.

See sphere example: https://github.com/mozman/ezdxf/blob/master/examples/r12writer.py

Parameters:

vertices – iterable of (x, y, z) tuples
faces – iterable of 3 or 4 vertex indices, indices have to be 0-based
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_polymesh(vertices: Iterable[Sequence[float]], size: tuple[int, int], closed=(False, False), layer: str = '0', color: int | None = None, linetype: str | None = None) → None¶

Add a POLYMESH entity. A POLYMESH is a mesh of m rows and n columns, each mesh vertex has its own x-, y- and z coordinates. The mesh can be closed in m- and/or n-direction. The vertices have to be in column order: (m0, n0), (m0, n1), (m0, n2), (m1, n0), (m1, n1), (m1, n2), …

See example: https://github.com/mozman/ezdxf/blob/master/examples/r12writer.py

Parameters:

vertices – iterable of (x, y, z) tuples, in column order
size – mesh dimension as (m, n)-tuple, requirement: len(vertices) == m*n
closed – (m_closed, n_closed) tuple, for closed mesh in m and/or n direction
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()
linetype – line type as string see add_line()

add_text(text: str, insert: Sequence[float] = (0, 0), height: float = 1.0, width: float = 1.0, align: str = 'LEFT', rotation: float = 0.0, oblique: float = 0.0, style: str = 'STANDARD', layer: str = '0', color: int | None = None) → None¶

Add a one line TEXT entity.

Parameters:

text – the text as string
insert – insert location as (x, y) tuple
height – text height in drawing units
width – text width as factor
align – text alignment, see table below
rotation – text rotation in degrees as float
oblique – oblique in degrees as float, vertical = 0 (default)
style – text style name as string, if FIXED-TABLES are written some predefined text styles are available, else text style is always 'STANDARD'.
layer – layer name as string see add_line()
color – color as AutoCAD Color Index (ACI) see add_line()

Vert/Horiz	Left	Center	Right
Top	`TOP_LEFT`	`TOP_CENTER`	`TOP_RIGHT`
Middle	`MIDDLE_LEFT`	`MIDDLE_CENTER`	`MIDDLE_RIGHT`
Bottom	`BOTTOM_LEFT`	`BOTTOM_CENTER`	`BOTTOM_RIGHT`
Baseline	`LEFT`	`CENTER`	`RIGHT`

The special alignments ALIGNED and FIT are not available.