Draft DXF
Description
Draft DXF is a software module used by the Std Open,
Std Import and
Std Export commands to handle the DXF file format.
From the user's point of view, the DXF import/export module will be loaded automatically when any of those commands are invoked and the file to open, import or export is a DXF file. The main difference between Std Open and the import command is that the former will create a new FreeCAD document and then do the import, whereas the later will import the DXF file and insert the result in the currently active document.
QCAD drawing exported to DXF, which is subsequently opened in FreeCAD
Importing
Two importers are available, which one is used can be specified under Edit → Preferences → Import-Export → DXF. One is built-in, C++-based and fast, the other is legacy, coded in Python, slower, and requires the installation of an add-on, but can handle some entities better and can create more refined FreeCAD objects. Both support all DXF versions starting from R12.
3D solids inside a DXF file are stored under a binary ACIS/SAT blob, which at the moment cannot be read by FreeCAD.
| Entity | C++ importer | Legacy importer |
|---|---|---|
| Lines | ✓ | ✓ |
| Polylines (and LWPOLYLINES) | ✓ | ✓ |
| Arcs | ✓ | ✓ |
| Circles | ✓ | ✓ |
| Ellipses | ✓ | ✓ |
| Splines | ✓ | ✓ |
| Texts & MTexts | ✓ | ✓ |
| Leaders | ✗ | ✓ |
| Layers | ✓ | ✓ |
| Points | ✓ | ✓ |
| Dimensions | ✓ | ✓ |
| Blocks | ✓ (Geometry only; texts, dimensions, and attributes inside blocks are skipped) |
✓ |
| Paper space objects | ✓ | ✓ |
| 3D Faces | ✗ | ✓ |
Exporting
There are also two exporters. The legacy exporter exports to the R12 DXF format, the C++ exporter to the R14 DXF format. Both formats can be handled by many applications.
| Feature | C++ exporter (R14) | Legacy exporter (R12) |
|---|---|---|
| Supported 2D Geometry | All except Bezier curves. Ellipses and Splines are exported natively. | All except Points. Ellipses and B-splines may be inaccurate or exported as polylines. |
| Points | ✓ (If the "Export points" preference is enabled) |
✗ |
| 3D Objects | Edges from faces are exported. Curved edges only if on XY plane. May create duplicate lines. | Exported as flattened 2D views. |
| Texts and Dimensions | ✗ | ✓ |
| Colors | ✗ | ✓ (Based on object line color) |
| Layers | ✓ (Mapped from object names) |
✓ (Mapped from layers and nested groups) |
| Compounds | ✗ | ✓ (Exported as blocks) |
Installing
For licensing reasons, the required DXF import/export libraries needed by the legacy version of the importer are not part of the FreeCAD source code. For more information see: FreeCAD and DXF Import.
Preferences
See Import Export Preferences.
DWG
Because the DWG format is a proprietary, closed and undocumented format it is hard for open-source projects like FreeCAD to support it. That is why FreeCAD relies on external converters to read and write DWG files. To import a DWG file a converter is used to create a DXF first, which can then be processed by the FreeCAD DXF importer. When exporting to DWG the opposite conversion happens: the DXF created by the FreeCAD DXF exporter is turned into a DWG.
Note that the DXF format allows a 1:1 conversion of the DWG format. All applications that can read and write DWG files can do the same with DXF files, with no data loss. So asking for DXF files instead of DWG files, and supplying DXF files in turn, should not cause any problems.
There is built-in support for the following DWG converters:
- LibreDWG (open-source, lacks support for some DWG entities).
- ODA File Converter (free).
- QCAD pro (commercial).
See Import Export Preferences and FreeCAD and DWG Import for more information.
Scripting
See also: Autogenerated API documentation and FreeCAD Scripting Basics.
To export objects to DXF use the export method of the importDXF module.
importDXF.export(objectslist, filename, nospline=False, lwPoly=False)
- For the Windows OS: use a / (forward slash) as the path separator in
filename.
Example:
import FreeCAD as App
import Draft
import importDXF
doc = App.newDocument()
polygon1 = Draft.make_polygon(3, radius=500)
polygon2 = Draft.make_polygon(5, radius=1500)
doc.recompute()
objects = [polygon1, polygon2]
importDXF.export(objects, "/home/user/Pictures/myfile.dxf")
- Drafting: Line, Polyline, Fillet, Arc, Arc From 3 Points, Circle, Ellipse, Rectangle, Polygon, B-Spline, Cubic Bézier Curve, Bézier Curve, Point, Facebinder, ShapeString, Hatch
- Annotation: Text, Dimension, Label, Annotation Styles, Annotation Scale
- Modification: Move, Rotate, Scale, Mirror, Offset, Trimex, Stretch, Clone, Array, Polar Array, Circular Array, Path Array, Path Link Array, Point Array, Point Link Array, Edit, Highlight Subelements, Join, Split, Upgrade, Downgrade, Convert Wire/B-Spline, Draft to Sketch, Set Slope, Flip Dimension, Shape 2D View
- Draft Tray: Working Plane, Set Style, Toggle Construction Mode, AutoGroup
- Snapping: Snap Lock, Snap Endpoint, Snap Midpoint, Snap Center, Snap Angle, Snap Intersection, Snap Perpendicular, Snap Extension, Snap Parallel, Snap Special, Snap Near, Snap Ortho, Snap Grid, Snap Working Plane, Snap Dimensions, Toggle Grid
- Miscellaneous: Apply Current Style, New Layer, Manage Layers, New Named Group, SelectGroup, Add to Layer, Add to Group, Add to Construction Group, Toggle Wireframe, Working Plane Proxy, Heal, Show Snap Toolbar
- Additional: Constraining, Pattern, Preferences, Import Export Preferences, DXF/DWG, SVG, OCA, DAT
- Context menu:
- Most objects: Edit
- Layer container: Add New Layer, Reassign Properties of All Layers, Merge Layer Duplicates
- Layer: Activate Layer, Reassign Properties of Layer, Select Layer Contents
- Text and label: Open Links
- Wire: Flatten
- Working plane proxy: Save Camera Position, Save Visibility of Objects
- Getting started
- Installation: Download, Windows, Linux, Mac, Additional components, Docker, AppImage, Ubuntu Snap
- Basics: About FreeCAD, Interface, Mouse navigation, Selection methods, Object name, Preferences, Workbenches, Document structure, Properties, Help FreeCAD, Donate
- Help: Tutorials, Video tutorials
- Workbenches: Std Base, Assembly, BIM, CAM, Draft, FEM, Inspection, Material, Mesh, OpenSCAD, Part, PartDesign, Points, Reverse Engineering, Robot, Sketcher, Spreadsheet, Surface, TechDraw, Test Framework
- Hubs: User hub, Power users hub, Developer hub
