DXF multilayer support (#1267)

* Test DXF export with text

* DXF multilayer support

Also supports:

* setting units
* setting color by layer
* setting line type by layer

* Apply transformation to bspline curve on DXF export

* Typing improvements

* Improve test coverage

---------

Co-authored-by: Lorenz Neureuter <hello@lorenz.space>

cadquery/occ_impl/exporters/__init__.py

@@ -15,7 +15,7 @@ from .svg import getSVG
 from .json import JsonMesh
 from .amf import AmfWriter
 from .threemf import ThreeMFWriter
-from .dxf import exportDXF
+from .dxf import exportDXF, DxfDocument
 from .vtk import exportVTP
 from .utils import toCompound
 

cadquery/occ_impl/exporters/dxf.py

@@ -1,56 +1,246 @@
-from ...cq import Workplane, Plane, Face
+"""DXF export utilities."""
+
+from typing import Any, Dict, List, Literal, Optional, Tuple, Union
+
+import ezdxf
+from ezdxf import units, zoom
+from ezdxf.entities import factory
+from OCP.GeomConvert import GeomConvert
+from OCP.gp import gp_Dir
+from typing_extensions import Self
+
+from ...cq import Face, Plane, Workplane
 from ...units import RAD2DEG
 from ..shapes import Edge
 from .utils import toCompound
 
-from OCP.gp import gp_Dir
+ApproxOptions = Literal["spline", "arc"]
-from OCP.GeomConvert import GeomConvert
+DxfEntityAttributes = Tuple[
-
+    Literal["ARC", "CIRCLE", "ELLIPSE", "LINE", "SPLINE",], Dict[str, Any]
-from typing import Optional, Literal
+]
-
-import ezdxf
-
-CURVE_TOLERANCE = 1e-9
 
 
-def _dxf_line(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
+class DxfDocument:
+    """Create DXF document from CadQuery objects.
 
-    msp.add_line(
+    A wrapper for `ezdxf <https://ezdxf.readthedocs.io/>`_ providing methods for
-        e.startPoint().toTuple(), e.endPoint().toTuple(),
+    converting :class:`cadquery.Workplane` objects to DXF entities.
+
+    The ezdxf document is available as the property ``document``, allowing most
+    features of ezdxf to be utilised directly.
+
+    .. rubric:: Example usage
+
+    .. code-block:: python
+        :caption: Single layer DXF document
+
+        rectangle = cq.Workplane().rect(10, 20)
+
+        dxf = DxfDocument()
+        dxf.add_shape(rectangle)
+        dxf.document.saveas("rectangle.dxf")
+
+    .. code-block:: python
+        :caption: Multilayer DXF document
+
+        rectangle = cq.Workplane().rect(10, 20)
+        circle = cq.Workplane().circle(3)
+
+        dxf = DxfDocument()
+        dxf = (
+            dxf.add_layer("layer_1", color=2)
+            .add_layer("layer_2", color=3)
+            .add_shape(rectangle, "layer_1")
+            .add_shape(circle, "layer_2")
+        )
+        dxf.document.saveas("rectangle-with-hole.dxf")
+    """
+
+    CURVE_TOLERANCE = 1e-9
+
+    def __init__(
+        self,
+        dxfversion: str = "AC1027",
+        setup: Union[bool, List[str]] = False,
+        doc_units: int = units.MM,
+        *,
+        metadata: Union[Dict[str, str], None] = None,
+        approx: Optional[ApproxOptions] = None,
+        tolerance: float = 1e-3,
+    ):
+        """Initialize DXF document.
+
+        :param dxfversion: :attr:`DXF version specifier <ezdxf-stable:ezdxf.document.Drawing.dxfversion>`
+            as string, default is "AC1027" respectively "R2013"
+        :param setup: setup default styles, ``False`` for no setup, ``True`` to set up
+            everything or a list of topics as strings, e.g. ``["linetypes", "styles"]``
+            refer to :func:`ezdxf-stable:ezdxf.new`.
+        :param doc_units: ezdxf document/modelspace :doc:`units <ezdxf-stable:concepts/units>`
+        :param metadata: document :ref:`metadata <ezdxf-stable:ezdxf_metadata>` a dictionary of name value pairs
+        :param approx: Approximation strategy for converting :class:`cadquery.Workplane` objects to DXF entities:
+
+            ``None``
+                no approximation applied
+            ``"spline"``
+                all splines approximated as cubic splines
+            ``"arc"``
+                all curves approximated as arcs and straight segments
+
+        :param tolerance: Approximation tolerance for converting :class:`cadquery.Workplane` objects to DXF entities.
+        """
+        if metadata is None:
+            metadata = {}
+
+        self._DISPATCH_MAP = {
+            "LINE": self._dxf_line,
+            "CIRCLE": self._dxf_circle,
+            "ELLIPSE": self._dxf_ellipse,
+        }
+
+        self.approx = approx
+        self.tolerance = tolerance
+
+        self.document = ezdxf.new(dxfversion=dxfversion, setup=setup, units=doc_units)  # type: ignore[attr-defined]
+        self.msp = self.document.modelspace()
+
+        doc_metadata = self.document.ezdxf_metadata()
+        for key, value in metadata.items():
+            doc_metadata[key] = value
+
+    def add_layer(
+        self, name: str, *, color: int = 7, linetype: str = "CONTINUOUS"
+    ) -> Self:
+        """Create a layer definition
+
+        Refer to :ref:`ezdxf layers <ezdxf-stable:layer_concept>` and
+        :doc:`ezdxf layer tutorial <ezdxf-stable:tutorials/layers>`.
+
+        :param name: layer definition name
+        :param color: color index. Standard colors include:
+            1 red, 2 yellow, 3 green, 4 cyan, 5 blue, 6 magenta, 7 white/black
+        :param linetype: ezdxf :doc:`line type <ezdxf-stable:concepts/linetypes>`
+        """
+        self.document.layers.add(name, color=color, linetype=linetype)
+
+        return self
+
+    def add_shape(self, workplane: Workplane, layer: str = "") -> Self:
+        """Add CadQuery shape to a DXF layer.
+
+        :param workplane: CadQuery Workplane
+        :param layer: layer definition name
+        """
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+
+        general_attributes = {}
+        if layer:
+            general_attributes["layer"] = layer
+
+        if self.approx == "spline":
+            edges = [
+                e.toSplines() if e.geomType() == "BSPLINE" else e for e in shape.Edges()
+            ]
+
+        elif self.approx == "arc":
+            edges = []
+
+            # this is needed to handle free wires
+            for el in shape.Wires():
+                edges.extend(Face.makeFromWires(el).toArcs(self.tolerance).Edges())
+
+        else:
+            edges = shape.Edges()
+
+        for edge in edges:
+            converter = self._DISPATCH_MAP.get(edge.geomType(), None)
+
+            if converter:
+                entity_type, entity_attributes = converter(edge)
+                entity = factory.new(
+                    entity_type, dxfattribs={**entity_attributes, **general_attributes}
+                )
+                self.msp.add_entity(entity)  # type: ignore[arg-type]
+            else:
+                _, entity_attributes = self._dxf_spline(edge, plane)
+                entity = ezdxf.math.BSpline(**entity_attributes)  # type: ignore[assignment]
+                self.msp.add_spline(
+                    dxfattribs=general_attributes
+                ).apply_construction_tool(entity)
+
+        zoom.extents(self.msp)
+
+        return self
+
+    @staticmethod
+    def _dxf_line(edge: Edge) -> DxfEntityAttributes:
+        """Convert a Line to DXF entity attributes.
+
+        :param edge: CadQuery Edge to be converted to a DXF line
+
+        :return: dictionary of DXF entity attributes for creating a line
+        """
+        return (
+            "LINE",
+            {"start": edge.startPoint().toTuple(), "end": edge.endPoint().toTuple(),},
         )
 
+    @staticmethod
+    def _dxf_circle(edge: Edge) -> DxfEntityAttributes:
+        """Convert a Circle to DXF entity attributes.
 
-def _dxf_circle(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
+        :param edge: CadQuery Edge to be converted to a DXF circle
 
-    geom = e._geomAdaptor()
+        :return: dictionary of DXF entity attributes for creating either a circle or arc
+        """
+        geom = edge._geomAdaptor()
         circ = geom.Circle()
 
-    r = circ.Radius()
+        radius = circ.Radius()
-    c = circ.Location()
+        location = circ.Location()
 
-    c_dy = circ.YAxis().Direction()
+        direction_y = circ.YAxis().Direction()
-    c_dz = circ.Axis().Direction()
+        direction_z = circ.Axis().Direction()
 
         dy = gp_Dir(0, 1, 0)
 
-    phi = c_dy.AngleWithRef(dy, c_dz)
+        phi = direction_y.AngleWithRef(dy, direction_z)
 
-    if c_dz.XYZ().Z() > 0:
+        if direction_z.XYZ().Z() > 0:
             a1 = RAD2DEG * (geom.FirstParameter() - phi)
             a2 = RAD2DEG * (geom.LastParameter() - phi)
         else:
             a1 = -RAD2DEG * (geom.LastParameter() - phi) + 180
             a2 = -RAD2DEG * (geom.FirstParameter() - phi) + 180
 
-    if e.IsClosed():
+        if edge.IsClosed():
-        msp.add_circle((c.X(), c.Y(), c.Z()), r)
+            return (
+                "CIRCLE",
+                {
+                    "center": (location.X(), location.Y(), location.Z()),
+                    "radius": radius,
+                },
+            )
         else:
-        msp.add_arc((c.X(), c.Y(), c.Z()), r, a1, a2)
+            return (
+                "ARC",
+                {
+                    "center": (location.X(), location.Y(), location.Z()),
+                    "radius": radius,
+                    "start_angle": a1,
+                    "end_angle": a2,
+                },
+            )
 
+    @staticmethod
+    def _dxf_ellipse(edge: Edge) -> DxfEntityAttributes:
+        """Convert an Ellipse to DXF entity attributes.
 
-def _dxf_ellipse(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
+        :param edge: CadQuery Edge to be converted to a DXF ellipse
 
-    geom = e._geomAdaptor()
+        :return: dictionary of DXF entity attributes for creating an ellipse
+        """
+        geom = edge._geomAdaptor()
         ellipse = geom.Ellipse()
 
         r1 = ellipse.MinorRadius()
@@ -60,26 +250,38 @@ def _dxf_ellipse(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
         xdir = ellipse.XAxis().Direction()
         xax = r2 * xdir.XYZ()
 
-    msp.add_ellipse(
+        return (
-        (c.X(), c.Y(), c.Z()),
+            "ELLIPSE",
-        (xax.X(), xax.Y(), xax.Z()),
+            {
-        r1 / r2,
+                "center": (c.X(), c.Y(), c.Z()),
-        geom.FirstParameter(),
+                "major_axis": (xax.X(), xax.Y(), xax.Z()),
-        geom.LastParameter(),
+                "ratio": r1 / r2,
+                "start_param": geom.FirstParameter(),
+                "end_param": geom.LastParameter(),
+            },
         )
 
+    @classmethod
+    def _dxf_spline(cls, edge: Edge, plane: Plane) -> DxfEntityAttributes:
+        """Convert a Spline to ezdxf.math.BSpline parameters.
 
-def _dxf_spline(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
+        :param edge: CadQuery Edge to be converted to a DXF spline
+        :param plane: CadQuery Plane
 
-    adaptor = e._geomAdaptor()
+        :return: dictionary of ezdxf.math.BSpline parameters
+        """
+        adaptor = edge._geomAdaptor()
         curve = GeomConvert.CurveToBSplineCurve_s(adaptor.Curve().Curve())
 
         spline = GeomConvert.SplitBSplineCurve_s(
-        curve, adaptor.FirstParameter(), adaptor.LastParameter(), CURVE_TOLERANCE
+            curve,
+            adaptor.FirstParameter(),
+            adaptor.LastParameter(),
+            cls.CURVE_TOLERANCE,
         )
 
         # need to apply the transform on the geometry level
-    spline.Transform(plane.fG.wrapped.Trsf())
+        spline.Transform(adaptor.Trsf())
 
         order = spline.Degree() + 1
         knots = list(spline.KnotSequence())
@@ -94,25 +296,25 @@ def _dxf_spline(e: Edge, msp: ezdxf.layouts.Modelspace, plane: Plane):
             pad = spline.NbKnots() - spline.LastUKnotIndex()
             poles += poles[:pad]
 
-    dxf_spline = ezdxf.math.BSpline(poles, order, knots, weights)
+        return (
-
+            "SPLINE",
-    msp.add_spline().apply_construction_tool(dxf_spline)
+            {
-
+                "control_points": poles,
-
+                "order": order,
-DXF_CONVERTERS = {
+                "knots": knots,
-    "LINE": _dxf_line,
+                "weights": weights,
-    "CIRCLE": _dxf_circle,
+            },
-    "ELLIPSE": _dxf_ellipse,
+        )
-    "BSPLINE": _dxf_spline,
-}
 
 
 def exportDXF(
     w: Workplane,
     fname: str,
-    approx: Optional[Literal["spline", "arc"]] = None,
+    approx: Optional[ApproxOptions] = None,
     tolerance: float = 1e-3,
-):
+    *,
+    doc_units: int = units.MM,
+) -> None:
     """
     Export Workplane content to DXF. Works with 2D sections.
 
@@ -122,33 +324,9 @@ def exportDXF(
         "spline" results in all splines being approximated as cubic splines. "arc" results
         in all curves being approximated as arcs and straight segments.
     :param tolerance: Approximation tolerance.
-
+    :param doc_units: ezdxf document/modelspace :doc:`units <ezdxf-stable:concepts/units>` (in. = ``1``, mm = ``4``).
     """
 
-    plane = w.plane
+    dxf = DxfDocument(approx=approx, tolerance=tolerance, doc_units=doc_units)
-    shape = toCompound(w).transformShape(plane.fG)
+    dxf.add_shape(w)
-
+    dxf.document.saveas(fname)
-    dxf = ezdxf.new()
-    msp = dxf.modelspace()
-
-    if approx == "spline":
-        edges = [
-            e.toSplines() if e.geomType() == "BSPLINE" else e for e in shape.Edges()
-        ]
-
-    elif approx == "arc":
-        edges = []
-
-        # this is needed to handle free wires
-        for el in shape.Wires():
-            edges.extend(Face.makeFromWires(el).toArcs(tolerance).Edges())
-
-    else:
-        edges = shape.Edges()
-
-    for e in edges:
-
-        conv = DXF_CONVERTERS.get(e.geomType(), _dxf_spline)
-        conv(e, msp, plane)
-
-    dxf.saveas(fname)

doc/apireference.rst

@@ -206,6 +206,7 @@ File Management and Export
     importers.importStep
     importers.importDXF
     exporters.export
+    occ_impl.exporters.dxf.DxfDocument
 
 
 Iteration Methods

doc/classreference.rst

@@ -101,3 +101,8 @@ Class Details
    :members:
 
 .. autofunction:: cadquery.occ_impl.assembly.toJSON
+
+.. autoclass:: cadquery.occ_impl.exporters.dxf.DxfDocument
+   :members:
+
+   .. automethod:: __init__

doc/conf.py

@@ -38,6 +38,7 @@ extensions = [
     "sphinx.ext.autodoc",
     "sphinx.ext.viewcode",
     "sphinx.ext.autosummary",
+    "sphinx.ext.intersphinx",
     "cadquery.cq_directive",
     "sphinx.ext.mathjax",
     "sphinx_autodoc_multimethod",
@@ -212,6 +213,11 @@ html_show_sphinx = False
 # Output file base name for HTML help builder.
 htmlhelp_basename = "CadQuerydoc"
 
+# -- Options for intersphinx --------------------------------------------------
+
+intersphinx_mapping = {
+    "ezdxf-stable": ("https://ezdxf.readthedocs.io/en/stable/", None),
+}
 
 # -- Options for LaTeX output --------------------------------------------------
 

doc/importexport.rst

@@ -239,17 +239,99 @@ optimum values that will produce an acceptable mesh.
 Exporting DXF
 ##############
 
+.. seealso::
+
+    :class:`cadquery.occ_impl.exporters.dxf.DxfDocument` for exporting multiple
+    Workplanes to one or many layers of a DXF document.
+
+Options
+-------
+
+``approx``
+    Approximation strategy for converting :class:`cadquery.Workplane` objects to DXF entities:
+
+        ``None``
+            no approximation applied
+        ``"spline"``
+            all splines approximated as cubic splines
+        ``"arc"``
+            all curves approximated as arcs and straight segments
+``tolerance``
+    Approximation tolerance for converting :class:`cadquery.Workplane` objects to DXF entities.
+    See `Approximation strategy`_.
+``doc_units``
+    Ezdxf document/modelspace :doc:`units <ezdxf-stable:concepts/units>`.
+    See `Units`_.
+
+.. code-block:: python
+    :caption: DXF document without options.
+
+    import cadquery as cq
+    from cadquery import exporters
+
+    result = cq.Workplane().box(10, 10, 10)
+
+    exporters.exportDXF(result, "/path/to/file/object.dxf")
+    # or
+    exporters.export(result, "/path/to/file/object.dxf")
+
+
+Units
+-----
+
+The default DXF document units are mm (:code:`doc_units = 4`).
+
+========= ===============
+doc_units Unit
+========= ===============
+0         Unitless
+1         Inches
+2         Feet
+3         Miles
+4         Millimeters
+5         Centimeters
+6         Meters
+========= ===============
+
+Document units can be set to any :doc:`unit supported by ezdxf <ezdxf-stable:concepts/units>`.
+
+.. code-block:: python
+    :caption: DXF document with units set to meters.
+
+    import cadquery as cq
+    from cadquery import exporters
+
+    result = cq.Workplane().box(10, 10, 10)
+
+    exporters.exportDXF(
+        result, "/path/to/file/object.dxf", doc_units=6,  # set DXF document units to meters
+    )
+
+    # or
+
+    exporters.export(
+        result,
+        "/path/to/file/object.dxf",
+        opt={"doc_units": 6},  # set DXF document units to meters
+    )
+
+
+.. _Approximation strategy:
+
+Approximation strategy
+----------------------
+
 By default, the DXF exporter will output splines exactly as they are represented by the OpenCascade kernel. Unfortunately some software cannot handle higher-order splines resulting in missing curves after DXF import. To resolve this, specify an approximation strategy controlled by the following options:
 
 * ``approx`` - ``None``, ``"spline"`` or ``"arc"``. ``"spline"`` results in all splines approximated with cubic splines. ``"arc"`` results in all curves approximated with arcs and line segments.
-* ``tolerance``: Acceptable error of the approximation, in the DXF's coordinate system. Defaults to 0.001 (1 thou for inch-scale drawings, 1 µm for mm-scale drawings).
+* ``tolerance``: Acceptable error of the approximation, in document/modelspace units. Defaults to 0.001 (1 thou for inch-scale drawings, 1 µm for mm-scale drawings).
 
 .. code-block:: python
-
+    :caption: DXF document with curves approximated with cubic splines.
 
     cq.exporters.exportDXF(
         result,
-        '/path/to/file/object.dxf',
+        "/path/to/file/object.dxf",
         approx="spline"
     )
 

tests/test_exporters.py

@@ -1,5 +1,5 @@
 """
-    Tests basic workplane functionality
+    Tests exporters
 """
 # core modules
 import os
@@ -16,6 +16,7 @@ from pytest import approx
 from cadquery import (
     exporters,
     importers,
+    Sketch,
     Workplane,
     Edge,
     Vertex,
@@ -24,6 +25,8 @@ from cadquery import (
     Location,
     Vector,
 )
+from cadquery.occ_impl.exporters.dxf import DxfDocument
+from cadquery.occ_impl.exporters.utils import toCompound
 from tests import BaseTest
 from OCP.GeomConvert import GeomConvert
 from OCP.BRepBuilderAPI import BRepBuilderAPI_MakeEdge
@@ -34,6 +37,11 @@ def tmpdir(tmp_path_factory):
     return tmp_path_factory.mktemp("out")
 
 
+@pytest.fixture(scope="module")
+def testdatadir():
+    return Path(__file__).parent.joinpath("testdata")
+
+
 @pytest.fixture()
 def box123():
     return Workplane().box(1, 2, 3)
@@ -59,6 +67,223 @@ def test_step_options(tmpdir):
     assert w.faces().size() == 6
 
 
+class TestDxfDocument(BaseTest):
+    """Test class DxfDocument."""
+
+    def test_line(self):
+        workplane = Workplane().line(1, 1)
+
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+        edges = shape.Edges()
+
+        result = DxfDocument._dxf_line(edges[0])
+
+        expected = ("LINE", {"start": (0.0, 0.0, 0.0), "end": (1.0, 1.0, 0.0)})
+
+        self.assertEqual(expected, result)
+
+    def test_circle(self):
+        workplane = Workplane().circle(1)
+
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+        edges = shape.Edges()
+
+        result = DxfDocument._dxf_circle(edges[0])
+
+        expected = ("CIRCLE", {"center": (0.0, 0.0, 0.0), "radius": 1.0})
+
+        self.assertEqual(expected, result)
+
+    def test_arc(self):
+        workplane = Workplane().radiusArc((1, 1), 1)
+
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+        edges = shape.Edges()
+
+        result_type, result_attributes = DxfDocument._dxf_circle(edges[0])
+
+        expected_type, expected_attributes = (
+            "ARC",
+            {"center": (1, 0, 0), "radius": 1, "start_angle": 90, "end_angle": 180,},
+        )
+
+        self.assertEqual(expected_type, result_type)
+        self.assertTupleAlmostEquals(
+            expected_attributes["center"], result_attributes["center"], 3
+        )
+        self.assertAlmostEqual(
+            expected_attributes["radius"], approx(result_attributes["radius"])
+        )
+        self.assertAlmostEqual(
+            expected_attributes["start_angle"], result_attributes["start_angle"]
+        )
+        self.assertAlmostEqual(
+            expected_attributes["end_angle"], result_attributes["end_angle"]
+        )
+
+    def test_ellipse(self):
+        workplane = Workplane().ellipse(2, 1, 0)
+
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+        edges = shape.Edges()
+
+        result_type, result_attributes = DxfDocument._dxf_ellipse(edges[0])
+
+        expected_type, expected_attributes = (
+            "ELLIPSE",
+            {
+                "center": (0, 0, 0),
+                "major_axis": (2.0, 0, 0),
+                "ratio": 0.5,
+                "start_param": 0,
+                "end_param": 6.283185307179586,
+            },
+        )
+
+        self.assertEqual(expected_type, result_type)
+        self.assertEqual(expected_attributes["center"], result_attributes["center"])
+        self.assertEqual(
+            expected_attributes["major_axis"], result_attributes["major_axis"]
+        )
+        self.assertEqual(expected_attributes["ratio"], result_attributes["ratio"])
+        self.assertEqual(
+            expected_attributes["start_param"], result_attributes["start_param"]
+        )
+        self.assertAlmostEqual(
+            expected_attributes["end_param"], result_attributes["end_param"]
+        )
+
+    def test_spline(self):
+        pts = [(0, 0), (0, 0.5), (1, 1)]
+        workplane = (
+            Workplane().spline(pts).close().extrude(1).edges("|Z").fillet(0.1).section()
+        )
+
+        plane = workplane.plane
+        shape = toCompound(workplane).transformShape(plane.fG)
+        edges = shape.Edges()
+
+        result_type, result_attributes = DxfDocument._dxf_spline(edges[0], plane)
+
+        expected_type, expected_attributes = (
+            "SPLINE",
+            {
+                "control_points": [
+                    (-0.032010295564216654, 0.2020130195642037, 0.0),
+                    (-0.078234124721739, 0.8475143728081896, 0.0),
+                    (0.7171193004814275, 0.9728923786984539, 0.0),
+                ],
+                "order": 3,
+                "knots": [
+                    0.18222956891558767,
+                    0.18222956891558767,
+                    0.18222956891558767,
+                    1.416096480384525,
+                    1.416096480384525,
+                    1.416096480384525,
+                ],
+                "weights": None,
+            },
+        )
+
+        self.assertEqual(expected_type, result_type)
+        self.assertAlmostEqual(
+            expected_attributes["control_points"], result_attributes["control_points"]
+        )
+        self.assertEqual(expected_attributes["order"], result_attributes["order"])
+        self.assertEqual(expected_attributes["knots"], result_attributes["knots"])
+        self.assertEqual(expected_attributes["weights"], result_attributes["weights"])
+
+    def test_add_layer_definition(self):
+        dxf = DxfDocument()
+        dxf.add_layer("layer_1")
+
+        self.assertIn("layer_1", dxf.document.layers)
+
+    def test_add_layer_definition_with_color(self):
+        dxf = DxfDocument()
+        dxf.add_layer("layer_1", color=2)
+        layer = dxf.document.layers.get("layer_1")
+
+        self.assertEqual(2, layer.color)
+
+    def test_add_layer_definition_with_linetype(self):
+        dxf = DxfDocument(setup=True)
+        dxf.add_layer("layer_1", linetype="CENTER")
+        layer = dxf.document.layers.get("layer_1")
+
+        self.assertEqual("CENTER", layer.dxf.linetype)
+
+    def test_add_shape_to_layer(self):
+        line = Workplane().line(0, 10)
+
+        dxf = DxfDocument(setup=True)
+
+        default_layer_names = set()
+        for layer in dxf.document.layers:
+            default_layer_names.add(layer.dxf.name)
+
+        dxf = dxf.add_layer("layer_1").add_shape(line, "layer_1")
+
+        expected_layer_names = default_layer_names.copy()
+        expected_layer_names.add("layer_1")
+
+        self.assertEqual({"0", "Defpoints"}, default_layer_names)
+
+        self.assertEqual(1, len(dxf.msp))
+        self.assertEqual({"0", "Defpoints", "layer_1"}, expected_layer_names)
+        self.assertEqual("layer_1", dxf.msp[0].dxf.layer)
+        self.assertEqual("LINE", dxf.msp[0].dxftype())
+
+    def test_set_dxf_version(self):
+        dxfversion = "AC1032"
+
+        dxf_default = DxfDocument()
+        dxf = DxfDocument(dxfversion=dxfversion)
+
+        self.assertNotEqual(dxfversion, dxf_default.document.dxfversion)
+        self.assertEqual(dxfversion, dxf.document.dxfversion)
+
+    def test_set_units(self):
+        doc_units = 17
+
+        dxf_default = DxfDocument()
+        dxf = DxfDocument(doc_units=17)
+
+        self.assertNotEqual(doc_units, dxf_default.document.units)
+        self.assertEqual(doc_units, dxf.document.units)
+
+    def test_set_metadata(self):
+        metadata = {"CUSTOM_KEY": "custom value"}
+
+        dxf = DxfDocument(metadata=metadata)
+
+        self.assertEqual(
+            metadata["CUSTOM_KEY"], dxf.document.ezdxf_metadata().get("CUSTOM_KEY"),
+        )
+
+    def test_add_shape_line(self):
+        workplane = Workplane().line(1, 1)
+        dxf = DxfDocument()
+        dxf.add_shape(workplane)
+
+        result = dxf.msp.query("LINE")[0]
+
+        expected = ezdxf.entities.line.Line.new(
+            dxfattribs={"start": (0.0, 0.0, 0.0), "end": (1.0, 1.0, 0.0),},
+        )
+
+        self.assertEqual(expected.dxf.start, result.dxf.start)
+        self.assertEqual(expected.dxf.end, result.dxf.end)
+
+    def test_DxfDocument_import(self):
+        assert isinstance(exporters.DxfDocument(), DxfDocument)
+
+
 class TestExporters(BaseTest):
     def _exportBox(self, eType, stringsToFind, tolerance=0.1, angularTolerance=0.1):
         """
@@ -420,3 +645,26 @@ def test_dxf_approx():
     assert _check_dxf_no_spline("limit2.dxf")
 
     assert w1.val().Area() == approx(w1_i2.val().Area(), 1e-3)
+
+
+def test_dxf_text(tmpdir, testdatadir):
+
+    w1 = (
+        Workplane("XZ")
+        .box(8, 8, 1)
+        .faces("<Y")
+        .workplane()
+        .text(
+            ",,", 10, -1, True, fontPath=str(Path(testdatadir, "OpenSans-Regular.ttf")),
+        )
+    )
+
+    fname = tmpdir.joinpath(f"dxf_text.dxf").resolve()
+    exporters.exportDXF(w1.section(), fname)
+
+    s2 = Sketch().importDXF(fname)
+    w2 = Workplane("XZ", origin=(0, -0.5, 0)).placeSketch(s2).extrude(-1)
+
+    assert w1.val().Volume() == approx(59.983287, 1e-2)
+    assert w2.val().Volume() == approx(w1.val().Volume(), 1e-2)
+    assert w2.intersect(w1).val().Volume() == approx(w1.val().Volume(), 1e-2)