Sketcher SketchObject
Contents
Introduction
A Sketcher SketchObject, or formally a Sketcher::SketchObject
, is the base element to create 2D objects with the Sketcher Workbench.
The Sketcher::SketchObject
is derived from Part Part2DObject, which means it is a Part Feature object specialized for 2D geometry. Like Part2DObject, the SketchObject can be attached to planes and faces. In addition, the SketchObject can handle geometrical constraints of the lines and curves that are drawn within it.
Simplified diagram of the relationships between the core objects in FreeCAD. The Sketcher::SketchObject
class is specialized for 2D shapes, and additionally it includes an extension to handle geometrical constraints of its elements.
Usage
- Switch to the Sketcher Workbench.
- Press
Sketcher NewSketch.
- Select a Sketch orientation: XY-plane, XZ-plane, or YZ-plane. Optionally also choose Reverse direction, and give an Offset value.
- Press OK.
Although the SketchObject can be used by itself to draw on a plane, it is most commonly used in conjunction with the PartDesign Workbench to create extruded solids.
- Switch to the PartDesign Workbench.
- Press
PartDesign Body.
- Press
PartDesign NewSketch.
- Select feature: XY_Plane (Base plane), XZ_Plane (Base plane), or YZ_Plane (Base plane).
- Press OK.
Properties
See Property for all property types that scripted objects can have.
A Sketcher SketchObject (Sketcher::SketchObject
class) is derived from a Part Part2DObject (Part::Part2DObject
class), therefore it shares all the latter's properties.
In addition to the properties described in Part Part2DObject, the basic Sketcher SketchObject has the following properties in the property editor. Hidden properties can be shown by using the Show all command in the context menu of the property editor.
Data
Attachment
- DataMap Mode, DataMap Reversed, DataAttachment Offset: same as Part Part2DObject. See Part Attachment for more information on all attachment mapping modes.
Sketch
- DataConstraints: named constraints, if they exist; otherwise it is an empty list
[]
.
Hidden properties Data
See Part Part2DObject for the rest of the hidden properties.
Base
- DataProxy (
PythonObject
): a custom class associated with this object. This only exists for the Python version. See Scripting.
Sketch
- DataGeometry (
GeometryList
): a list of Part geometries that exist inside the sketch. - DataExternal Geometry (
LinkSubList
): a list of Part geometries outside this Sketch that are used for reference.
View
Auto Constraints
- ViewAutoconstraints (
Bool
): iftrue
it will try setting constraints when the geometry is drawn.
Visibility automation
- ViewEditing Workbench (
String
): name of the workbench to activate when editing the sketch; it defaults toSketcherWorkbench
. - ViewHide Dependent (
Bool
): iftrue
all objects that depend on the sketch are hidden when opening the sketch. - ViewRestore Camera (
Bool
): iftrue
the camera position is saved before opening the sketch, and is restored after closing it. - ViewShow Links (
Bool
): iftrue
all objects used in links to external geometry are shown when opening the sketch. - ViewShow Support (
Bool
): iftrue
all objects this sketch is attached to are shown when opening the sketch.
Hidden properties View
Base
- ViewProxy (
PythonObject
): a custom view provider class associated with this object. This only exists for the Python version. See Scripting.
Visibility automation
- ViewTempo Vis (
PythonObject
): a custom class associated with this object, that handles hiding and showing other objects when opening and closing the sketch.
All other view properties, including hidden properties, are those of the base Part Feature object.
Scripting
See also: FreeCAD Scripting Basics, and scripted objects.
See Part Feature for the general information on adding objects to the document.
A SketchObject is created with the addObject()
method of the document.
import FreeCAD as App
doc = App.newDocument()
obj = App.ActiveDocument.addObject("Sketcher::SketchObject", "Sketch")
obj.Label = "Custom label"
This basic Sketcher::SketchObject
doesn't have a Proxy object so it can't be fully used for sub-classing.
Therefore, for Python subclassing, you should create the Sketcher::SketchObjectPython
object.
import FreeCAD as App
doc = App.newDocument()
obj = App.ActiveDocument.addObject("Sketcher::SketchObjectPython", "CustomSketch")
obj.Label = "Custom label"
- The tools: New sketch, Edit sketch, Leave sketch, View sketch, View section, Map sketch to face, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch
- Sketcher geometries: Point, Line by 2 point, Create an arc, Arc, Arc by 3 Point, Create a circle, Circle, Circle by 3 Point, Create a conic, Ellipse by center, Ellipse by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola, Create a B-spline, Create B-spline, Create periodic B-pline, Polyline (multiple-point line), Rectangle, Create regular polygon, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Create Regular Polygon, Slot, Fillet, Trimming, Extend, External Geometry, CarbonCopy, Construction Mode
- Sketcher constraints
- Geometric constraints Coincident, Point On Object, Vertical, Horizontal, Parallel, Perpendicular, Tangent, Equal Length, Symmetric, Constrain Block
- Dimensional constraints Lock, Horizontal Distance, Vertical Distance, Distance, Radius, Internal Angle, Snell's Law, Internal Alignment, Toggle reference/driving constraint,
- Sketcher tools Select solver DOFs, Close Shape, Connect Edges, Select Constraints, Select Origin, Select Vertical Axis, Select Horizontal Axis, Select Redundant Constraints, Select Conflicting Constraints, Select Elements Associated with constraints, Show/Hide internal geometry, Symmetry, Clone, Copy, Move, Rectangular Array, Delete All Geometry, Delete All Constraints
- Sketcher B-spline tools Show/Hide B-spline degree, Show/Hide B-spline control polygon, Show/Hide B-spline curvature comb, Show/Hide B-spline knot multiplicity, Convert Geometry to B-spline, Increase degree, Increase knot multiplicity, Decrease knot multiplicity
- Sketcher virtual space Switch Virtual Space

- 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; Arch, Draft, FEM, Image, Inspection, Mesh, OpenSCAD, Part, PartDesign, Path, Points, Raytracing, Reverse Engineering, Sketcher, Spreadsheet, Start, Surface, TechDraw, Test Framework, Web
- Deprecated or unmaintained workbenches: Complete, Drawing, Robot
- Hubs: User hub, Power users hub, Developer hub
- Core: App DocumentObject
- Basic: App FeaturePython, App GeoFeature, Part Feature, Mesh Feature, Fem FemMeshObject
- Internal shapes: Part TopoShape, Mesh MeshObject, Fem FemMesh
- Structure: App DocumentObjectGroup (Std Group), App Part (Std Part), App Link (Std LinkMake)
- Derived: Part Part2DObject, Sketcher SketchObject, PartDesign Body, PartDesign Feature