Curve Class

Protected serialization constructor for internal use.

Gets the maximum algebraic degree of any span or a good estimate if curve spans are not algebraic.

Gets the dimension of the object.

The dimension is typically three. For parameter space trimming curves the dimension is two. In rare cases the dimension can be one or greater than three.

Indicates if this object has been disposed or the document it originally belonged to has been disposed.

Gets or sets the domain of the curve.

Returns true if the Brep.TryConvertBrep function will be successful for this object

Gets true if this class has any custom information attached to it through UserData.

Gets a value indicating whether or not this curve is a closed curve.

true if object can be accurately modified with "squishy" transformations like projections, shears, and non-uniform scaling.

If true this object may not be modified. Any properties or functions that attempt to modify this object when it is set to "IsReadOnly" will throw a NotSupportedException.

Gets a value indicating whether or not this curve is considered to be Periodic.

Returns true if the curve is a cubic, non-rational, uniform NURBS curve that is either periodic or has natural end conditions. Otherwise, false is returned.

Tests an object to see if it is valid.

Useful for switch statements that need to differentiate between basic object types like points, curves, surfaces, and so on.

Evaluates point at the end of the curve.

Evaluates point at the start of the curve.

Gets the number of non-empty smooth (c-infinity) spans in the curve.

Evaluate unit tangent vector at the end of the curve.

Evaluates the unit tangent vector at the start of the curve.

List of custom information that is attached to this class.

Dictionary of custom information attached to this class. The dictionary is actually user data provided as an easy to use shareable set of information.

Gets the amount of user strings.

If this curve is closed, then modify it so that the start/end point is at curve parameter t.

Changes the dimension of a curve.

Determines the orientation (counterclockwise or clockwise) of a closed, planar curve in the world XY plane. Only works with simple (no self intersections) closed, planar curves.

Determines the orientation (counterclockwise or clockwise) of a closed, planar curve in a given plane. Only works with simple (no self intersections) closed, planar curves.

Determines the orientation (counterclockwise or clockwise) of a closed, planar curve. Only works with simple (no self intersections) closed, planar curves.

Determines the orientation (counterclockwise or clockwise) of a closed, planar curve in a given plane. Only works with simple (no self intersections) closed, planar curves.

Finds parameter of the point on a curve that is closest to testPoint. If the maximumDistance parameter is > 0, then only points whose distance to the given point is <= maximumDistance will be returned. Using a positive value of maximumDistance can substantially speed up the search.

Finds the parameter of the point on a curve that is closest to testPoint. If the maximumDistance parameter is > 0, then only points whose distance to the given point is <= maximumDistance will be returned. Using a positive value of maximumDistance can substantially speed up the search.

Gets closest points between this and another curves.

Finds the object (and the closest point in that object) that is closest to this curve.

Breps, surfaces, curves and point clouds are examples of objects that can be passed to this function.

Finds the object (and the closest point in that object) that is closest to this curve.

Breps, surfaces, curves and point clouds are examples of objects that can be passed to this function.

Looks for segments that are shorter than tolerance that can be combined. For NURBS of degree greater than 1, spans are combined by removing knots. Similarly for NURBS segments of polycurves. Otherwise, RemoveShortSegments() is called. Does not change the domain, but it will change the relative parameterization.

If this piece of geometry is a component in something larger, like a BrepEdge in a Brep, then this function returns the component index.

Assigns a parent object and a sub-object index to this.

Computes the relationship between a point and a closed curve region. This curve must be closed or the return value will be Unset. Both curve and point are projected to the World XY plane.

Computes the relationship between a point and a closed curve region. This curve must be closed or the return value will be Unset.

Computes the relationship between a point and a closed curve region. This curve must be closed or the return value will be Unset.

Creates a polycurve consisting of two tangent arc segments that connect two points and two directions.

Creates an arc-line-arc blend curve between two curves. The output is generally a PolyCurve with three segments: arc, line, arc. In some cases, one or more of those segments will be absent because they would have 0 length. If there is only a single segment, the result will either be an ArcCurve or a LineCurve.

Create a Blend curve between two existing curves.

Create a Blend curve between two existing curves.

Makes a curve blend between 2 curves at the parameters specified with the directions and continuities specified

Calculates the boolean difference between two closed, planar curves. Note, curves must be co-planar.

Calculates the boolean difference between a closed planar curve, and a list of closed planar curves. Note, curves must be co-planar.

Calculates the boolean difference between two closed, planar curves. Note, curves must be co-planar.

Calculates the boolean difference between a closed planar curve, and a list of closed planar curves. Note, curves must be co-planar.

Calculates the boolean intersection of two closed, planar curves. Note, curves must be co-planar.

Calculates the boolean intersection of two closed, planar curves. Note, curves must be co-planar.

Calculates curve Boolean regions, which trims and splits curves based on their overlapping regions.

Curve Boolean method, which trims and splits curves based on their overlapping regions.

Calculates the boolean union of two or more closed, planar curves. Note, curves must be co-planar.

Calculates the boolean union of two or more closed, planar curves. Note, curves must be co-planar.

Constructs a control-point of degree=3 (or less).

Constructs a curve from a set of control-point locations.

Creates a third curve from two curves that are planar in different construction planes. The new curve looks the same as each of the original curves when viewed in each plane.

Computes the fillet arc for a curve filleting operation.

Rounds the corners of a kinked curve with arcs of a single, specified radius.

Creates a tangent arc between two curves and trims or extends the curves to the arc.

Interpolates a sequence of points. Used by InterpCurve Command This routine works best when degree=3.

Interpolates a sequence of points. Used by InterpCurve Command This routine works best when degree=3.

Interpolates a sequence of points. Used by InterpCurve Command This routine works best when degree=3.

Changes a curve end to meet a specified curve with a specified continuity.

Constructs a mean, or average, curve from two curves.

Constructs a mean, or average, curve from two curves.

Removes kinks from a curve. Periodic curves deform smoothly without kinks.

Removes kinks from a curve. Periodic curves deform smoothly without kinks.

Creates a soft edited curve from an existing curve using a smooth field of influence.

Creates outline curves created from a text string. The functionality is similar to what you find in Rhino's TextObject command or TextEntity.Explode() in RhinoCommon.

Creates curves between two open or closed input curves. Uses the control points of the curves for finding tween curves. That means the first control point of first curve is matched to first control point of the second curve and so on. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Creates curves between two open or closed input curves. Uses the control points of the curves for finding tween curves. That means the first control point of first curve is matched to first control point of the second curve and so on. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Creates curves between two open or closed input curves. Make the structure of input curves compatible if needed. Refits the input curves to have the same structure. The resulting curves are usually more complex than input unless input curves are compatible and no refit is needed. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Creates curves between two open or closed input curves. Make the structure of input curves compatible if needed. Refits the input curves to have the same structure. The resulting curves are usually more complex than input unless input curves are compatible and no refit is needed. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Creates curves between two open or closed input curves. Use sample points method to make curves compatible. This is how the algorithm works: Divides the two curves into an equal number of points, finds the midpoint between the corresponding points on the curves and interpolates the tween curve through those points. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Creates curves between two open or closed input curves. Use sample points method to make curves compatible. This is how the algorithm works: Divides the two curves into an equal number of points, finds the midpoint between the corresponding points on the curves and interpolates the tween curve through those points. There is no matching of curves direction. Caller must match input curves direction before calling the function.

Evaluate the curvature vector at a curve parameter.

Returns a CRC calculated from the information that defines the object. This CRC can be used as a quick way to see if two objects are not identical.

Evaluate the derivatives at the specified curve parameter.

Evaluate the derivatives at the specified curve parameter.

Actively reclaims unmanaged resources that this instance uses.

For derived class implementers.

This method is called with argument true when class user calls Dispose(), while with argument false when the Garbage Collector invokes the finalizer, or Finalize() method.

You must reclaim all used unmanaged resources in both cases, and can use this chance to call Dispose on disposable fields if the argument is true.

Also, you must call the base virtual method within your overriding method.

Divides this curve at fixed steps along a defined contour line.

Divide the curve into a number of equal-length segments.

Divide the curve into a number of equal-length segments.

Divide the curve into specific length segments.

Divide the curve into specific length segments.

Divide the curve into specific length segments.

Divide the curve into specific length segments.

Calculates 3d points on a curve where the linear distance between the points is equal.

Determines whether two curves travel more or less in the same direction.

Constructs an exact duplicate of this Curve.

Constructs an exact duplicate of this curve.

Duplicates curve segments. Explodes polylines, polycurves and G1 discontinuous NURBS curves. Single segment curves, such as lines, arcs, unkinked NURBS curves, are duplicated.

Constructs a light copy of this object. By "light", it is meant that the same underlying data is used until something is done to attempt to change it. For example, you could have a shallow copy of a very heavy mesh object and the same underlying data will be used when doing things like inspecting the number of faces on the mesh. If you modify the location of one of the mesh vertices, the shallow copy will create a full duplicate of the underlying mesh data and the shallow copy will become a deep copy.

If you want to keep a copy of this class around by holding onto it in a variable after a command completes, call EnsurePrivateCopy to make sure that this class is not tied to the document. You can call this function as many times as you want.

Determines whether the specified object is equal to the current object.

Where possible, analytically extends curve to include the given domain. This will not work on closed curves. The original curve will be identical to the restriction of the resulting curve to the original curve domain.

Where possible, analytically extends curve to include the given domain. This will not work on closed curves. The original curve will be identical to the restriction of the resulting curve to the original curve domain.

Extends a curve to a point.

Extends a curve until it intersects a collection of objects.

Extends a curve by a specific length.

Extends a curve by an Arc until it intersects a collection of objects.

Extends a curve by a line until it intersects a collection of objects.

Extends a curve on a surface.

Extends a curve on a surface.

Returns the parameter values of all local extrema. Parameter values are in increasing order so consecutive extrema define an interval on which each component of the curve is monotone. Note, non-periodic curves always return the end points.

Fairs a curve object. Fair works best on degree 3 (cubic) curves. Attempts to remove large curvature variations while limiting the geometry changes to be no more than the specified tolerance.

Creates a constant-radius fillet surface between a surface and the curve.

Creates a surface between two surfaces, with a fixed rail curve on the first surface.

Passively reclaims unmanaged resources when the class user did not explicitly call Dispose().

Local minimization for point on a curve with tangent perpendicular to N.

Fits a new curve through an existing curve.

Returns a 3d frame at a parameter.

Bounding box solver. Gets the world axis aligned bounding box for the geometry.

Aligned Bounding box solver. Gets the plane aligned bounding box.

Aligned Bounding box solver. Gets the world axis aligned bounding box for the transformed geometry.

Aligned Bounding box solver. Gets the plane aligned bounding box.

Returns the type of conic section based on the curve's shape.

Returns the type of conic section based on the curve's shape.

Convert a NURBS curve parameter to a curve parameter.

Calculates the minimum and maximum distances between two curves. This function is useful for computing curve deviation. If you are not computing curve deviation, use .

Finds points at which to cut a pair of curves so that a fillet of given radius can be inserted.

Serves as the default hash function.

Gets the length of the curve with a fractional tolerance of 1.0e-8.

Get the length of the curve.

Get the length of a sub-section of the curve with a fractional tolerance of 1e-8.

Get the length of a sub-section of the curve.

Search for a location on the curve, near seedParmameter, that is perpendicular to a test point.

Search for a location on the curve, near seedParmameter, that is perpendicular to a test point.

Search for a location on the curve, near seedParmameter, that is tangent to a test point.

Search for a location on the curve, near seedParmameter, that is tangent to a test point.

Searches for a derivative, tangent, or curvature discontinuity.

Searches for a derivative, tangent, or curvature discontinuity.

Convert a curve parameter to a NURBS curve parameter.

Populates a System.Runtime.Serialization.SerializationInfo with the data needed to serialize the target object.

Gets a collection of perpendicular frames along the curve. Perpendicular frames are also known as 'Zero-twisting frames' and they minimize rotation from one frame to the next.

Gets the Type of the current instance.

Gets user string from this geometry.

Gets a copy of all (user key string, user value string) pairs attached to this geometry.

Does a NURBS curve representation of this curve exist?

Returns a curve's inflection points. An inflection point is a location on a curve at which the sign of the curvature (i.e., the concavity) changes. The curvature at these locations is always 0.

Returns a curve's inflection points. An inflection point is a location on a curve at which the sign of the curvature (i.e., the concavity) changes. The curvature at these locations is always 0.

Test a curve to see if it can be represented by an arc or circle within RhinoMath.ZeroTolerance.

Test a curve to see if it can be represented by an arc or circle within the given tolerance.

Test a curve to see if it can be represented by a circle within RhinoMath.ZeroTolerance.

Test a curve to see if it can be represented by a circle within the given tolerance.

Decide if it makes sense to close off this curve by moving the endpoint to the start based on start-end gap size and length of curve as approximated by chord defined by 6 points.

Decide if it makes sense to close off this curve by moving the endpoint to the start based on start-end gap size and length of curve as approximated by chord defined by 6 points.

Test continuity at a curve parameter value.

Test a curve to see if it can be represented by an ellipse within RhinoMath.ZeroTolerance.

Test a curve to see if it can be represented by an ellipse within a given tolerance.

Test a curve to see if it lies in a specific plane.

Test a curve to see if it lies in a specific plane.

Test a curve to see if it is linear to within RhinoMath.ZeroTolerance units (1e-12).

Test a curve to see if it is linear to within the custom tolerance.

Test a curve for planarity.

Test a curve for planarity.

Several types of Curve can have the form of a polyline including a degree 1 NurbsCurve, a PolylineCurve, and a PolyCurve all of whose segments are some form of polyline. IsPolyline tests a curve to see if it can be represented as a polyline.

Used to quickly find short curves.

Used to quickly find short curves.

Determines if an object is valid. Also provides a report on errors if this object happens not to be valid.

Joins a collection of curve segments together.

Joins a collection of curve segments together.

Joins a collection of curve segments together.

Joins a collection of curve segments together.

Gets the parameter along the curve which coincides with a given length along the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Gets the parameter along the curve which coincides with a given length along the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Gets the parameter along the curve which coincides with a given length along the curve.

Gets the parameter along the curve which coincides with a given length along the curve.

Find parameter of the point on a curve that is locally closest to the testPoint. The search for a local close point starts at a seed parameter.

If IsClosed, just return true. Otherwise, decide if curve can be closed as follows: Linear curves polylinear curves with 2 segments, NURBS with 3 or less control points cannot be made closed. Also, if tolerance > 0 and the gap between start and end is larger than tolerance, curve cannot be made closed. Adjust the curve's endpoint to match its start point.

If possible, converts the object into a form that can be accurately modified with "squishy" transformations like projections, shears, an non-uniform scaling.

Makes adjustments to the ends of one or both input curves so that they meet at a point.

Returns a curve's maximum curvature points. The maximum curvature points identify where the curvature starts to decrease in both directions from the points.

Returns a curve's maximum curvature points. The maximum curvature points identify where the curvature starts to decrease in both directions from the points.

Creates a shallow copy of the current Object.

Computes an estimate of the number of bytes that this object is using in memory.

For derived classes implementers.

Defines the necessary implementation to free the instance from being constant.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve. A fractional tolerance of 1e-8 is used in this version of the function.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve.

Input the parameter of the point on the curve that is a prescribed arc length from the start of the curve.

Offsets this curve. If you have a nice offset, then there will be one entry in the array. If the original curve had kinks or the offset curve had self intersections, you will get multiple segments in the output array.

Offsets this curve. If you have a nice offset, then there will be one entry in the array. If the original curve had kinks or the offset curve had self intersections, you will get multiple segments in the output array.

Offsets this curve. If you have a nice offset, then there will be one entry in the array. If the original curve had kinks or the offset curve had self intersections, you will get multiple segments in the output array.

Finds a curve by offsetting an existing curve normal to a surface. The caller is responsible for ensuring that the curve lies on the input surface.

Offset a curve on a brep face surface. This curve must lie on the surface.

This overload allows to specify a surface point at which the offset will pass.

Offset this curve on a brep face surface. This curve must lie on the surface.

Offset a curve on a surface. This curve must lie on the surface.

This overload allows to specify a surface point at which the offset will pass.

Offset a curve on a surface. This curve must lie on the surface.

Offset a curve on a brep face surface. This curve must lie on the surface.

This overload allows to specify different offsets for different curve parameters.

Offset this curve on a surface. This curve must lie on the surface.

This overload allows to specify different offsets for different curve parameters.

Finds a curve by offsetting an existing curve tangent to a surface. The caller is responsible for ensuring that the curve lies on the input surface.

Is called when a non-constant operation occurs.

Return a 3d frame at a parameter. This is slightly different than FrameAt in that the frame is computed in a way so there is minimal rotation from one frame to the next.

Determines whether two coplanar simple closed curves are disjoint or intersect; otherwise, if the regions have a containment relationship, discovers which curve encloses the other.

Determines if two coplanar curves collide (intersect).

Evaluates point at a curve parameter.

Gets a point at a certain length along the curve. The length must be non-negative and less than or equal to the length of the curve. Lengths will not be wrapped when the curve is closed or periodic.

Gets a point at a certain normalized length along the curve. The length must be between or including 0.0 and 1.0, where 0.0 equals the start of the curve and 1.0 equals the end of the curve.

Projects a Curve onto a Brep along a given direction.

Projects a Curve onto a collection of Breps along a given direction.

Projects a collection of Curves onto a collection of Breps along a given direction.

Projects a Curve onto a collection of Breps along a given direction.

Projects a collection of Curves onto a collection of Breps along a given direction.

Projects a curve to a mesh using a direction and tolerance.

Projects a curve to a set of meshes using a direction and tolerance.

Projects a curve to a set of meshes using a direction and tolerance.

Constructs a curve by projecting an existing curve to a plane.

Pulls this curve to a brep face and returns the result of that operation.

Pull a curve to a BrepFace using closest point projection.

Makes a polyline approximation of the curve and gets the closest point on the mesh for each point on the curve. Then it "connects the points" so that you have a polyline on the mesh.

Rebuild a curve with a specific point count.

Looks for segments that are shorter than tolerance that can be removed. Does not change the domain, but it will change the relative parameterization.

Reverses the direction of the curve.

Offsets a closed curve in the following way: pProject the curve to a plane with given normal. Then, loose Offset the projection by distance + blend_radius and trim off self-intersection. THen, Offset the remaining curve back in the opposite direction by blend_radius, filling gaps with blends. Finally, use the elevations of the input curve to get the correct elevations of the result.

Offsets a closed curve in the following way: pProject the curve to a plane with given normal. Then, loose Offset the projection by distance + blend_radius and trim off self-intersection. THen, Offset the remaining curve back in the opposite direction by blend_radius, filling gaps with blends. Finally, use the elevations of the input curve to get the correct elevations of the result.

Offsets a closed curve in the following way: pProject the curve to a plane with given normal. Then, loose Offset the projection by distance + blend_radius and trim off self-intersection. THen, Offset the remaining curve back in the opposite direction by blend_radius, filling gaps with blends. Finally, use the elevations of the input curve to get the correct elevations of the result.

Rotates the object about the specified axis. A positive rotation angle results in a counter-clockwise rotation about the axis (right hand rule).

Scales the object by the specified factor. The scale is centered at the origin.

Forces the curve to end at a specified point. Not all curve types support this operation.

Forces the curve to start at a specified point. Not all curve types support this operation.

Attach a user string (key,value combination) to this geometry.

Returns a geometrically equivalent PolyCurve.

The PolyCurve has the following properties

1. All the PolyCurve segments are LineCurve, PolylineCurve, ArcCurve, or NurbsCurve.

2. The NURBS Curves segments do not have fully multiple interior knots.

3. Rational NURBS curves do not have constant weights.

4. Any segment for which IsLinear() or IsArc() is true is a Line, Polyline segment, or an Arc.

5. Adjacent co-linear or co-circular segments are combined.

6. Segments that meet with G1-continuity have there ends tuned up so that they meet with G1-continuity to within machine precision.

Same as SimplifyCurve, but simplifies only the last two segments at "side" end.

Smooths a curve by averaging the positions of control points in a specified region.

Smooths a curve by averaging the positions of control points in a specified region.

Get the domain of the curve span with the given index. Use the SpanCount property to test how many spans there are.

Splits (divides) the curve at the specified parameter. The parameter must be in the interior of the curve's domain.

Splits (divides) the curve at a series of specified parameters. The parameter must be in the interior of the curve domain.

Splits a curve into pieces using a polysurface.

Splits a curve into pieces using a surface.

Splits a curve into pieces using a polysurface.

Splits a curve into pieces using a surface.

Evaluates the unit tangent vector at a curve parameter.

Converts a curve into polycurve consisting of arc segments. Sections of the input curves that are nearly straight are converted to straight-line segments.

Create a JSON string representation of this object

Constructs a NURBS curve representation of this curve.

Constructs a NURBS curve representation of this curve.

Gets a polyline approximation of a curve.

Gets a polyline approximation of a curve.

Gets a polyline approximation of a curve.

Evaluate the torsion of a curve at a parameter. Sometimes also called the "second curvature", torsion is the rate of change of a curve's osculating plane.

Returns a string that represents the current object.

Transforms the geometry. If the input Transform has a SimilarityType of OrientationReversing, you may want to consider flipping the transformed geometry after calling this function when it makes sense. For example, you may want to call Flip() on a Brep after transforming it.

Translates the object along the specified vector.

Translates the object along the specified vector.

Removes portions of the curve outside the specified interval.

Shortens a curve by a given length

Removes portions of the curve outside the specified interval.

Try to convert this curve into an Arc using RhinoMath.ZeroTolerance.

Try to convert this curve into an Arc using a custom tolerance.

Try to convert this curve into an Arc using RhinoMath.ZeroTolerance.

Try to convert this curve into an Arc using a custom tolerance.

Try to convert this curve into a circle using RhinoMath.ZeroTolerance.

Try to convert this curve into a Circle using a custom tolerance.

Try to convert this curve into an Ellipse within RhinoMath.ZeroTolerance.

Try to convert this curve into an Ellipse using a custom tolerance.

Try to convert this curve into an Ellipse within RhinoMath.ZeroTolerance.

Try to convert this curve into an Ellipse using a custom tolerance.

Test a curve for planarity and return the plane.

Test a curve for planarity and return the plane.

Several types of Curve can have the form of a polyline including a degree 1 NurbsCurve, a PolylineCurve, and a PolyCurve all of whose segments are some form of polyline. IsPolyline tests a curve to see if it can be represented as a polyline.

Several types of Curve can have the form of a polyline including a degree 1 NurbsCurve, a PolylineCurve, and a PolyCurve all of whose segments are some form of polyline. IsPolyline tests a curve to see if it can be represented as a polyline.