geomss.geom.nurbs

Class BasicNurbsCurve

java.lang.Object

geomss.geom.AbstractGeomElement<T>

geomss.geom.AbstractCurve<NurbsCurve>

geomss.geom.nurbs.NurbsCurve

geomss.geom.nurbs.BasicNurbsCurve

All Implemented Interfaces:

Curve<NurbsCurve>, GeomElement<NurbsCurve>, ParametricGeometry<NurbsCurve>, Transformable<NurbsCurve>, j2me.io.Serializable, java.lang.Cloneable, java.lang.Comparable, javolution.lang.Immutable, javolution.lang.Reusable, javolution.lang.ValueType, javolution.xml.XMLSerializable

public final class BasicNurbsCurve
extends NurbsCurve
implements javolution.lang.ValueType

A basic implementation of a parametric NURBS curve.

Modified by: Joseph A. Huwaldt

Version:

November 28, 2015

Author:

Samuel Gerber, Date: May 14, 2009, Version 1.0.

Field Summary

Fields inherited from class geomss.geom.AbstractCurve

GTOL

Fields inherited from class geomss.geom.AbstractGeomElement

RESOURCES

Method Summary

Modifier and Type	Method and Description
BasicNurbsCurve	copy() Returns a copy of this BasicNurbsCurve instance allocated by the calling thread (possibly on the stack).
BasicNurbsCurve	copyToReal() Return a copy of this object with any transformations or subranges removed (applied).
boolean	equals(java.lang.Object obj) Compares this BasicNurbsCurve against the specified object for strict equality (same values and same units).
Point	getBoundsMax() Return the coordinate point representing the maximum bounding box corner (e.g.: max X, max Y, max Z).
Point	getBoundsMin() Return the coordinate point representing the minimum bounding box corner of this geometry element (e.g.: min X, min Y, min Z).
java.util.List<ControlPoint>	getControlPoints() Return a list of control points for this curve.
int	getDegree() Return the degree of the NURBS curve.
KnotVector	getKnotVector() Return the knot vector of this curve.
int	getPhyDimension() Returns the number of physical dimensions of the geometry element.
Point	getRealPoint(double s) Calculate a point on the curve for the given parametric distance along the curve, p(s).
java.util.List<Vector<Length>>	getSDerivatives(double s, int grade) Calculate all the derivatives from 0 to grade with respect to parametric distance on the curve for the given parametric distance along the curve, d^{grade}p(s)/d^{grade}s.
Unit<Length>	getUnit() Returns the unit in which the control points in this curve are stated.
int	hashCode() Returns the hash code for this parameter.
BasicNurbsCurve	immutable() Return an immutable version of this NURBS curve.
static BasicNurbsCurve	newInstance(ControlPoint[] cps, int degree, double... uK) Create a NURBS curve from the given control points, knots and degree.
static BasicNurbsCurve	newInstance(java.util.List<ControlPoint> cpList, KnotVector uKnots) Generate a NURBS curve from the given control points and the given knot vector.
static void	recycle(BasicNurbsCurve instance) Recycles a BasicNurbsCurve instance immediately (on the stack when executing in a StackContext).
void	reset() Resets the internal state of this object to its default values.
int	size() Returns the number of child-elements that make up this geometry element.
BasicNurbsCurve	to(Unit<Length> unit) Returns the equivalent to this curve but stated in the specified unit.
BasicNurbsCurve	toDimension(int newDim) Return the equivalent of this curve converted to the specified number of physical dimensions.
javolution.text.Text	toText() Returns the text representation of this geometry element that consists of the name followed by the control point values, followed by the knot vector.

Methods inherited from class geomss.geom.nurbs.NurbsCurve

getArcLength, getArcLength, getTransformed, gridToTolerance, insertKnot, intersect, isDegenerate, isLine, isPlanar, isValid, mergeKnotVector, refineKnotVector, refineKnotVector, removeKnot, reverse, splitAt, toNurbs, toNurbs

Methods inherited from class geomss.geom.AbstractCurve

extractGrid, getArcLength, getBinormal, getBinormal, getClosest, getClosest, getClosest, getClosest, getClosest, getClosest, getCurvature, getCurvature, getDerivatives, getEnclosedArea, getFarthest, getFarthest, getFarthest, getLimitPoint, getParDimension, getPoint, getPoint, getPointAtArcLength, getPrincipalNormal, getPrincipalNormal, getRealPoint, getSDerivative, getSDerivatives, getTangencyPoint, getTangent, getTangent, getTorsion, getTorsion, getVariationOfCurvature, getVariationOfCurvature, intersect, intersect, intersect, intersect, isCircular, splitAt

Methods inherited from class geomss.geom.AbstractGeomElement

addChangeListener, clone, compareTo, getAllUserData, getID, getName, getUserData, putAllUserData, putUserData, removeChangeListener, removeUserData, setName, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface geomss.geom.GeomElement

addChangeListener, getAllUserData, getID, getName, getUserData, putAllUserData, putUserData, removeChangeListener, removeUserData, setName

Methods inherited from interface java.lang.Comparable

compareTo

Method Detail

newInstance

public static BasicNurbsCurve newInstance(ControlPoint[] cps,
                                          int degree,
                                          double... uK)

Create a NURBS curve from the given control points, knots and degree.

Parameters:

cps - Array of control points. May not be null.

degree - Degree of the NURBS curve

uK - Knot values. May not be null.

Returns:

A new NURBS curve

Throws:

java.lang.IllegalArgumentException - if the knot vector is not valid.

newInstance

public static BasicNurbsCurve newInstance(java.util.List<ControlPoint> cpList,
                                          KnotVector uKnots)

Generate a NURBS curve from the given control points and the given knot vector.

Parameters:

cpList - List of control points. May not be null.

uKnots - Knot vector for the curve. May not be null.

Returns:

A new NURBS curve.

Throws:

java.lang.IllegalArgumentException - if the knot vector is not consistent with the number of control points.

size

public int size()

Returns the number of child-elements that make up this geometry element. This implementation returns the number of control points in this NURBS curve.

Specified by:

size in interface GeomElement<NurbsCurve>

Returns:

The number of control points in this curve.

getPhyDimension

public int getPhyDimension()

Returns the number of physical dimensions of the geometry element.

Specified by:

getPhyDimension in interface GeomElement<NurbsCurve>

Returns:

The number of physical dimensions of this geometry element.

getControlPoints

public java.util.List<ControlPoint> getControlPoints()

Return a list of control points for this curve.

Specified by:

getControlPoints in class NurbsCurve

Returns:

the ordered control points

getKnotVector

public KnotVector getKnotVector()

Return the knot vector of this curve.

Specified by:

getKnotVector in class NurbsCurve

Returns:

The knot vector.

getDegree

public int getDegree()

Return the degree of the NURBS curve.

Specified by:

getDegree in class NurbsCurve

Returns:

degree of curve

getRealPoint

public Point getRealPoint(double s)

Calculate a point on the curve for the given parametric distance along the curve, p(s).

Specified by:

getRealPoint in interface Curve<NurbsCurve>

Parameters:

s - parametric distance to calculate a point for (0.0 to 1.0 inclusive).

Returns:

the calculated point

getSDerivatives

public java.util.List<Vector<Length>> getSDerivatives(double s,
                                                      int grade)

Calculate all the derivatives from 0 to grade with respect to parametric distance on the curve for the given parametric distance along the curve, d^{grade}p(s)/d^{grade}s.

Example:
1st derivative (grade = 1), this returns [p(s), dp(s)/ds];
2nd derivative (grade = 2), this returns [p(s), dp(s)/ds, d^2p(s)/d^2s]; etc.

Specified by:

getSDerivatives in interface Curve<NurbsCurve>

Parameters:

s - Parametric distance to calculate derivatives for (0.0 to 1.0 inclusive).

grade - The maximum grade to calculate the derivatives for (1=1st derivative, 2=2nd derivative, etc)

Returns:

A list of derivatives up to the specified grade of the curve at the specified parametric position.

Throws:

java.lang.IllegalArgumentException - if the grade is < 0.

getBoundsMin

public Point getBoundsMin()

Return the coordinate point representing the minimum bounding box corner of this geometry element (e.g.: min X, min Y, min Z).

Specified by:

getBoundsMin in interface GeomElement<NurbsCurve>

Returns:

The minimum bounding box coordinate for this geometry element.

Throws:

java.lang.IndexOutOfBoundsException - if this list contains no geometry.

getBoundsMax

public Point getBoundsMax()

Return the coordinate point representing the maximum bounding box corner (e.g.: max X, max Y, max Z).

Specified by:

getBoundsMax in interface GeomElement<NurbsCurve>

Returns:

The maximum bounding box coordinate for this geometry element.

Throws:

java.lang.IndexOutOfBoundsException - if this list contains no elements.

getUnit

public Unit<Length> getUnit()

Returns the unit in which the control points in this curve are stated.

Specified by:

getUnit in interface GeomElement<NurbsCurve>

Returns:

The unit that this curves points are stated in.

to

public BasicNurbsCurve to(Unit<Length> unit)
                   throws ConversionException

Returns the equivalent to this curve but stated in the specified unit.

Specified by:

to in interface Curve<NurbsCurve>

Specified by:

to in interface GeomElement<NurbsCurve>

Specified by:

to in interface ParametricGeometry<NurbsCurve>

Parameters:

unit - The length unit of the curve to be returned. May not be null.

Returns:

An equivalent to this curve but stated in the specified unit.

Throws:

ConversionException - if the the input unit is not a length unit.

toDimension

public BasicNurbsCurve toDimension(int newDim)

Return the equivalent of this curve converted to the specified number of physical dimensions. If the number of dimensions is greater than this element, then zeros are added to the additional dimensions. If the number of dimensions is less than this element, then the extra dimensions are simply dropped (truncated). If the new dimensions are the same as the dimension of this element, then this element is simply returned.

Specified by:

toDimension in interface Curve<NurbsCurve>

Specified by:

toDimension in interface GeomElement<NurbsCurve>

Specified by:

toDimension in interface ParametricGeometry<NurbsCurve>

Parameters:

newDim - The dimension of the curve to return.

Returns:

The equivalent of this curve converted to the new dimensions.

copy

public BasicNurbsCurve copy()

Returns a copy of this BasicNurbsCurve instance allocated by the calling thread (possibly on the stack).

Specified by:

copy in interface Curve<NurbsCurve>

Specified by:

copy in interface GeomElement<NurbsCurve>

Specified by:

copy in interface ParametricGeometry<NurbsCurve>

Specified by:

copy in interface javolution.lang.ValueType

Returns:

an identical and independent copy of this object.

copyToReal

public BasicNurbsCurve copyToReal()

Return a copy of this object with any transformations or subranges removed (applied).

Specified by:

copyToReal in interface Curve<NurbsCurve>

Specified by:

copyToReal in interface GeomElement<NurbsCurve>

Returns:

A copy of this object with any transformations or subranges removed (applied).

immutable

public BasicNurbsCurve immutable()

Return an immutable version of this NURBS curve. This implementation simply returns this BasicNurbsCurve instance.

Specified by:

immutable in class NurbsCurve

Returns:

an immutable version of this curve.

reset

public void reset()

Resets the internal state of this object to its default values.

Specified by:

reset in interface javolution.lang.Reusable

Overrides:

reset in class AbstractGeomElement<NurbsCurve>

equals

public boolean equals(java.lang.Object obj)

Compares this BasicNurbsCurve against the specified object for strict equality (same values and same units).

Overrides:

equals in class AbstractGeomElement<NurbsCurve>

Parameters:

obj - the object to compare with.

Returns:

true if this object is identical to that object; false otherwise.

hashCode

public int hashCode()

Returns the hash code for this parameter.

Overrides:

hashCode in class AbstractGeomElement<NurbsCurve>

Returns:

the hash code value.

toText

public javolution.text.Text toText()

Returns the text representation of this geometry element that consists of the name followed by the control point values, followed by the knot vector. For example:

   {aCurve = {{{1 ft, 0 ft}, 1.0}, {{0 ft, 1 ft}, 0.25}, {{-1 ft, 0 ft}, 1.0}},{degree=2,{0.0, 0.0, 0.0, 1.0, 1.0, 1.0}}}
 

If there is no name, then the output looks like this:

   {{{{1 ft, 0 ft}, 1.0}, {{0 ft, 1 ft}, 0.25}, {{-1 ft, 0 ft}, 1.0}},{degree=2,{0.0, 0.0, 0.0, 1.0, 1.0, 1.0}}}
 

Specified by:

toText in interface GeomElement<NurbsCurve>

Overrides:

toText in class NurbsCurve

Returns:

the text representation of this geometry element.

recycle

public static void recycle(BasicNurbsCurve instance)

Recycles a BasicNurbsCurve instance immediately (on the stack when executing in a StackContext).

Parameters:

instance - The instance to be recycled.