Use Freehand to create hand-drawn splines directly in the viewport.
Use the Freehand Spline tool to create hand-drawn splines using a mouse or other pointing device. You can constrain the spline to be drawn only on selected objects in the scene which then automatically follows their contours.
![](../images/GUID-98924321-B871-4EDC-A128-360F2B472F36.png)
Piped icing created by drawing a freehand spline constrained to two objects: a donut and plate.
Interface
Rendering and Interpolation rollouts
Most spline-based shapes share these parameters. For details, see the Rendering and Interpolation rollouts in the Spline Primitives and Extended Splines topic.
Freehand Spline rollout, Create mode
![](../images/GUID-598A868E-D4F5-432D-AA9D-4AA7267A1E6B.png)
Rollout shown before spline is drawn.
- Show Knots
- Displays knots on the spline.
Create group
- Granularity
- The number of cursor position samples taken before a knot is created.
- Threshold
- Sets how far the cursor must move before a new knot is created. A higher value increases the distance.
- Constrain
- Constrains the spline to selected objects in the scene.
- Pick Object button
- Enables Object Selection mode for constraining objects. When you have finished picking objects, click again to complete the operation.
- Clear
- Clears the list of selected objects.
- End Create On Button Up
- When enabled, creates a Freehand spline when the mouse button is released. When disabled, the shape is continued when the mouse button is pressed again, automatically connecting the open end of the spline; you must press Esc or right-click in the viewport to finish drawing.
Options group
- Curved/Straight toggle
- Sets whether the segments between knots are curved or straight.
- Closed
- Draws a line between the beginning and the end of the spline to close it.
- Normals
- Shows the resulting normals of the constrained spline in the viewport.
- Offset
- Offsets the position of the hand-drawn spline away from the surface of the constraining object.
Statistics group
- Number of Splines
- Displays the number of splines in the shape.
- Original Knots
- Shows the number of knots automatically created while drawing the spline (0 before drawing).
- New Knots
- Shows the new number of knots (0 before drawing).
Freehand Spline rollout, Modify mode
![](../images/GUID-6869E0C3-5EA2-4060-B37D-504C9DAF8C1A.png)
Rollout shown once the spline has been created.
- Show Knots
- Displays knots on the spline.
Options group
- Sampling
- Sets the sampling amount. Values greater than zero progressively reduce neighboring knots, smoothing the result.
- Curved/Straight toggle
- Sets whether the segments between knots are curved or straight.
- Closed
- Draws a line between the beginning and the end of the spline to close it.
- Normals
- Shows the resulting normals of the constrained spline in the viewport.
- Offset
- Offsets the position of the hand-drawn spline away from the surface of the constraining object.
Statistics group
- Number of Splines
- Displays the number of splines in the shape.
- Orig Knots
- Shows the number of knots automatically created while drawing the spline.
- New Knots
- Shows the new number of knots (0 before drawing).
Procedures
To create a freehand spline:
- From the
Create panel, turn on
Shapes.
- From the drop-down list, choose Splines.
- In the Object Type rollout, click Freehand.
- Set Threshold and Granularity to adjust the sampling when drawing, and set any additional options such as Rendering options, End Create On Button Up, and Offset.
Tip: Check Enable in Renderer if you want the result to be visible when rendered.
- In a viewport, drag the cursor to draw the desired shape.
- Release the mouse button to complete the shape. If the End Create On Button Up option is disabled, press the Esc key or right-click in the viewport to finish.
Tip: After drawing a Freehand spline, use the Spline Relax and Spline Overlap modifiers to fine-tune the results.
To constrain a Freehand spline to one or more objects in a scene:
- From the
Create panel, turn on
Shapes.
- From the drop-down list, choose Splines.
- In the Object Type rollout, click Freehand.
- In the Freehand Spline rollout, enable the Constrain option.
If an object is already selected it in the scene, it will be automatically added to the Constrain list.
- Click Pick Object and select objects from the scene.
- Click the blue Pick Object button again to disable it.
- In a viewport, drag the cursor over the selected object(s) to draw a shape.
The resulting spline will not go outside the edges of any constraining objects and will automatically follow the contours of the shapes.
- Release the mouse button to complete the shape. If the End Create On Button Up option is disabled, press the Esc key or right-click in the viewport to finish.
Tip: After drawing a constrained Freehand spline, use the Spline Relax and Spline Overlap modifiers to fine-tune the results.