Edit curves
Curves can be edited by changing their control-point structure.
Turn curve points on
![](../image/command_icons/pointson.png)
PointsOn
Display curve and surface control points.
![](../image/command_icons/pointsoff_rt.png)
PointsOff
![](../image/command_icons/editpton.png)
EditPtOn
Displays edit points on curves or SubDs.
![](../image/command_icons/solidpton.png)
SolidPtOn
Turn on pseudo control points for polysurfaces.
Insert or remove control points
![](../image/command_icons/insertcontrolpoint.png)
InsertControlPoint
Add control points to a curve or a row of control points to a surface.
![](../image/command_icons/inserteditpoint_rt.png)
InsertEditPoint
Add edit points to a curve.
![](../image/command_icons/insertkink.png)
InsertKink
Add kinks to a curve.
![](../image/command_icons/insertknot.png)
InsertKnot
Add knots to curves or surfaces.
![](../image/command_icons/removeknot.png)
RemoveKnot
Delete specified knots from a curve or surface.
![](../image/command_icons/removemultiknot.png)
RemoveMultiKnot
Remove multiple knots from curves and surfaces.
![](../image/command_icons/makeperiodic.png)
MakePeriodic
Remove the kink from the start/end of a curve or surface.
![](../image/command_icons/makenonperiodic.png)
MakeNonPeriodic
Insert a kink at the start/end of a curve or surface.
Change control point structure
![](../image/command_icons/changedegree.png)
ChangeDegree
Change the degree of the polynomial that defines the curve or surface by adding or subtracting control points between knot spans, while maintaining the knot structure.
![](../image/command_icons/convert_arcs.png)
Convert
Change a curve to polyline or arc segments.
![](../image/command_icons/_no_toolbar_button.png)
ConvertToBeziers
Change the structure of a NURBS object to a Bézier object.
![](../image/command_icons/crvseam.png)
CrvSeam
Change the seam (start/end) location on closed curves.
![](../image/command_icons/fair.png)
Fair
Remove large curvature variations in a curve while limiting the geometry changes to the specified tolerance.
![](../image/command_icons/fitcrv.png)
FitCrv
Make a non-rational NURBS curve of a specified degree that matches the input curve to within the specified tolerance.
![](../image/command_icons/makenonperiodic.png)
MakeNonPeriodic
Insert a kink at the start/end of a curve or surface.
![](../image/command_icons/makeperiodic.png)
MakePeriodic
Remove the kink from the start/end of a curve or surface.
![](../image/command_icons/makeuniform.png)
MakeUniform
Make the object knot vectors uniform without changing the control point locations.
![](../image/command_icons/makeuniformuv_makeuniform_rt.png)
MakeUniformUV
Make the surface knots uniform in u or v direction.
![](../image/command_icons/rebuild.png)
Rebuild
Reconstruct curves, surfaces, and extrusion objects to a specified degree and control point number.
![](../image/command_icons/rebuildcrvnonuniform.png)
RebuildCrvNonUniform
Interactively modify selected curves by non-uniformly re-spacing the control points.
![](../image/command_icons/removemultiknot.png)
RemoveMultiKnot
Remove multiple knots from curves and surfaces.
![](../image/command_icons/_no_toolbar_button.png)
Reparameterize
Recalculate an object's parameter space to match its 3-D geometry.
![](../image/command_icons/simplifycrv.png)
SimplifyCrv
Replace each curve segment that has the geometry of a line or an arc with a true line or arc.
![](../image/command_icons/smooth.png)
Smooth
Average the positions of curve and surface control points and mesh vertices and evens out the spacing to remove unwanted detail and loops.
![](../image/command_icons/weight.png)
Weight
Edit the weight of a curve or surface control point.
Interactive editing
These commands allow interactive curve editing.
![](../image/command_icons/fixedlengthcrvedit.png)
FixedLengthCrvEdit
Drag points on a curve to change its shape without changing the curve's length.
![](../image/command_icons/extractsubcrv.png)
ExtractSubCrv
Separate or duplicate polycurve segments.
![](../image/command_icons/hbar.png)
HBar
Edit a curve or surface with Bézier curve editing handles.
![](../image/command_icons/insertcontrolpoint.png)
InsertControlPoint
Add control points to a curve or a row of control points to a surface.
![](../image/command_icons/inserteditpoint_rt.png)
InsertEditPoint
Add edit points to a curve.
![](../image/command_icons/insertkink.png)
InsertKink
Add kinks to a curve.
![](../image/command_icons/insertknot.png)
InsertKnot
Add knots to curves or surfaces.
![](../image/command_icons/insertlineintocrv.png)
InsertLineIntoCrv
Flatten the curve segment between picked points.
![](../image/command_icons/match.png)
Match
Change a curve end to meet another curve or surface edge with a specified continuity.
![](../image/command_icons/matchcurvedir.png)
MatchCrvDir
Change a curve's direction to match another curve's direction.
![](../image/command_icons/moveuvn.png)
MoveUVN
Move curve or surface control points along the u, v, and normal directions of the object.
![](../image/command_icons/rebuildcrvnonuniform.png)
RebuildCrvNonUniform
Interactively modify selected curves by non-uniformly re-spacing the control points.
![](../image/command_icons/removeknot.png)
RemoveKnot
Delete specified knots from a curve or surface.
![](../image/command_icons/setpt.png)
SetPt
Moves selected points and control points of objects to a specified location in the x, y, and/or z directions.
![](../image/command_icons/softeditcrv.png)
SoftEditCrv
Move the surrounding curve area smoothly relative to the distance.
![](../image/command_icons/subcrv.png)
SubCrv
Shorten a curve to the new picked endpoints and select.
Curve analysis
These commands gather information about the structure of a curve.
![](../image/command_icons/curve deviation.png)
CrvDeviation
Report the maximum and minimum distances between two curves.
![](../image/command_icons/crvend_rt.png)
CrvEnd
Place a point object at the end of a curve.
![](../image/command_icons/crvseam.png)
CrvSeam
Change the seam (start/end) location on closed curves.
![](../image/command_icons/crvstart.png)
CrvStart
Place a point object at the start of a curve.
![](../image/command_icons/curvature_rt.png)
Curvature
Evaluate the curvature of a curve or surface.
![](../image/command_icons/curvaturegraph.png)
CurvatureGraph
Evaluate curve or surface curvature with a graph.
![](../image/command_icons/direction.png)
Dir
Display and edit an object's normal direction.
![](../image/command_icons/domain_rt.png)
Domain
Report the domain of a curve or surface.
![](../image/command_icons/editpton.png)
EditPtOn
Displays edit points on curves or SubDs.
![](../image/command_icons/extractpt.png)
ExtractPt
Duplicate curve control or edit points, surface control points, and mesh vertices.
![](../image/command_icons/gcon.png)
GCon
Report the geometric continuity between two curves.
![](../image/command_icons/radius.png)
Radius
Report the radius of a curve.