Toolbar Menu

Geometry Fix



The Smooth command averages the positions of curve and surface control points and mesh vertices in a specified region.

The Smooth command evens out the spacing of selected control points in small increments. This command is useful for removing unwanted detail, and for removing loops in curves and surfaces.

On mesh objects use the Weld command before smoothing in order to prevent the mesh from pulling apart.


To smooth part of a curve or surface

  1. Select a curve, surface, or mesh to smooth.
  2. To smooth a region, turn on control points, and select the control points in the region of the object to smooth.
  3. Start the Smooth command.
  4. Click the check boxes for the coordinate directions and adjust the Smooth factor.
    The selected control points will move slightly, smoothing the curve or surface.

To set one check box and clear the others

Smooth Options

Smooth X / Y / Z

Smooths only in the specified x, y, or z direction.


Fix Boundaries

Prevents edges and endpoints from being included.

Meshes: Vertices along naked edges will not be modified.

Curves: End control points will not be modified.

Surfaces: The control points along the boundaries of the surface will not be modified. The edges and trims of trimmed surfaces will be modified if they do not coincide with the surface boundary.


World / CPlane / Object coordinates

Use world or construction plane or object u, v, and n coordinates to determine the direction of the smoothing.

Smooth factor per step

Sets an amount of smoothing.

0 to 1

The curve control point toward the average.

Greater than 1

The curve control point moves past the average.


The curve control point moves away from the average (roughing).

Number of smooth steps

Specifies the number of steps to iterate the smoothing factor through.


Command-line options


Type subcrv to select part of a curve as input.

See also

Edit curves

Edit surfaces




Rhinoceros 6 © 2010-2019 Robert McNeel & Associates. 16-May-2019