Sketch.addThreePointArcSlot Method

Parent Object: Sketch
Defined in namespace "adsk::fusion" and the header file is <Fusion/Sketch/Sketch.h>

Description

Creates the geometry that represents a three-point arc slot. The two end points define the start and end of the arc that defines the center line of the slot, and the third point specifies a point that results in defining the radius. Geometric constraints are automatically added to the geometry to maintain the slot shape, and optionally, dimensions are created to control the size. The created geometry and dimensions are returned.

Syntax

"sketch_var" is a variable referencing a Sketch object.

# Uses no optional arguments.
returnValue = sketch_var.addThreePointArcSlot(startPoint, endPoint, pointOnArc, width)

# Uses optional arguments.
returnValue = sketch_var.addThreePointArcSlot(startPoint, endPoint, pointOnArc, width, createWidthDimension)
"sketch_var" is a variable referencing a Sketch object.

#include <Fusion/Sketch/Sketch.h>

// Uses no optional arguments.
returnValue = sketch_var->addThreePointArcSlot(startPoint, endPoint, pointOnArc, width);

// Uses optional arguments.
returnValue = sketch_var->addThreePointArcSlot(startPoint, endPoint, pointOnArc, width, createWidthDimension);
"sketch_var" is a variable referencing a Sketch object.

// Uses no optional arguments.
returnValue = sketch_var.addThreePointArcSlot(startPoint, endPoint, pointOnArc, width);

// Uses Optional arguments.
returnValue = sketch_var.addThreePointArcSlot(startPoint, endPoint, pointOnArc, width, createWidthDimension);

Return Value

Type Description
Base[] Returns an array containing the start point arc, the end point arc, the two arcs that define the sides of the slot, the construction arc that runs through the spine of the slot, and optionally the width dimension constraint that was created. Returns an empty array if the operation failed.

Parameters

Name Type Description
startPoint Base The start point of the arc that defines the center line of the slot. It can be a SketchPoint or Point3D object. If a SketchPoint is provided, the slot becomes dependent on that point and will recompute if the point moves.
endPoint Base The end point of the arc that defines the center line of the slot. It can be a SketchPoint or Point3D object. If a SketchPoint is provided, the slot becomes dependent on that point and will recompute if the point moves.
pointOnArc Point3D A Point3D that lies on the arc and defines the arc's curvature. The startPoint, endPoint, and pointOnArc must be three non-collinear points so a valid arc can be defined through them, similar to a three-point arc.
width ValueInput A ValueInput object that defines the width of the slot. The ValueInput can define either a real value or an expression string. If it is a real value, it defines the width of the slot in centimeters.

When using a ValueInput created using a string, it's the same as creating a parameter in the user-interface. You can specify any valid expression, i.e. "5", "5 in", "5 in / 2", "5 + Length" that defines a length.

The width must be greater than zero and strictly less than twice the radius of the base arc, otherwise the slot is invalid.
createWidthDimension boolean Specifies if a dimension constraint and its associated parameter is created to control the width of the slot.

This is an optional argument whose default value is False.

Version

Introduced in version September 2026