Class QuadCurve2D
 Direct Known Subclasses:
QuadCurve2D.Double
,QuadCurve2D.Float
QuadCurve2D
class defines a quadratic parametric curve
segment in (x,y)
coordinate space.
This class is only the abstract superclass for all objects that store a 2D quadratic curve segment. The actual storage representation of the coordinates is left to the subclass.
 Since:
 1.2

Nested Class Summary
Modifier and TypeClassDescriptionstatic class
A quadratic parametric curve segment specified withdouble
coordinates.static class
A quadratic parametric curve segment specified withfloat
coordinates. 
Constructor Summary
ModifierConstructorDescriptionprotected
This is an abstract class that cannot be instantiated directly. 
Method Summary
Modifier and TypeMethodDescriptionclone()
Creates a new object of the same class and with the same contents as this object.boolean
contains
(double x, double y) Tests if the specified coordinates are inside the boundary of theShape
, as described by the definition of insideness.boolean
contains
(double x, double y, double w, double h) Tests if the interior of theShape
entirely contains the specified rectangular area.boolean
Tests if a specifiedPoint2D
is inside the boundary of theShape
, as described by the definition of insideness.boolean
Tests if the interior of theShape
entirely contains the specifiedRectangle2D
.Returns an integerRectangle
that completely encloses theShape
.Returns a high precision and more accurate bounding box of theShape
than thegetBounds
method.abstract Point2D
Returns the control point.abstract double
getCtrlX()
Returns the X coordinate of the control point indouble
precision.abstract double
getCtrlY()
Returns the Y coordinate of the control point indouble
precision.double
Returns the flatness, or maximum distance of a control point from the line connecting the end points, of thisQuadCurve2D
.static double
getFlatness
(double[] coords, int offset) Returns the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the control points stored in the indicated array at the indicated index.static double
getFlatness
(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Returns the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the indicated control points.double
Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of thisQuadCurve2D
.static double
getFlatnessSq
(double[] coords, int offset) Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the control points stored in the indicated array at the indicated index.static double
getFlatnessSq
(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the indicated control points.abstract Point2D
getP1()
Returns the start point.abstract Point2D
getP2()
Returns the end point.Returns an iteration object that defines the boundary of the shape of thisQuadCurve2D
.getPathIterator
(AffineTransform at, double flatness) Returns an iteration object that defines the boundary of the flattened shape of thisQuadCurve2D
.abstract double
getX1()
Returns the X coordinate of the start point indouble
in precision.abstract double
getX2()
Returns the X coordinate of the end point indouble
precision.abstract double
getY1()
Returns the Y coordinate of the start point indouble
precision.abstract double
getY2()
Returns the Y coordinate of the end point indouble
precision.boolean
intersects
(double x, double y, double w, double h) Tests if the interior of theShape
intersects the interior of a specified rectangular area.boolean
Tests if the interior of theShape
intersects the interior of a specifiedRectangle2D
.void
setCurve
(double[] coords, int offset) Sets the location of the end points and control points of thisQuadCurve2D
to thedouble
coordinates at the specified offset in the specified array.abstract void
setCurve
(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Sets the location of the end points and control point of this curve to the specifieddouble
coordinates.void
Sets the location of the end points and control points of thisQuadCurve2D
to the coordinates of thePoint2D
objects at the specified offset in the specified array.void
Sets the location of the end points and control point of thisQuadCurve2D
to the specifiedPoint2D
coordinates.void
Sets the location of the end points and control point of thisQuadCurve2D
to the same as those in the specifiedQuadCurve2D
.static int
solveQuadratic
(double[] eqn) Solves the quadratic whose coefficients are in theeqn
array and places the noncomplex roots back into the same array, returning the number of roots.static int
solveQuadratic
(double[] eqn, double[] res) Solves the quadratic whose coefficients are in theeqn
array and places the noncomplex roots into theres
array, returning the number of roots.static void
subdivide
(double[] src, int srcoff, double[] left, int leftoff, double[] right, int rightoff) Subdivides the quadratic curve specified by the coordinates stored in thesrc
array at indicessrcoff
throughsrcoff
+ 5 and stores the resulting two subdivided curves into the two result arrays at the corresponding indices.void
subdivide
(QuadCurve2D left, QuadCurve2D right) Subdivides thisQuadCurve2D
and stores the resulting two subdivided curves into theleft
andright
curve parameters.static void
subdivide
(QuadCurve2D src, QuadCurve2D left, QuadCurve2D right) Subdivides the quadratic curve specified by thesrc
parameter and stores the resulting two subdivided curves into theleft
andright
curve parameters.

Constructor Details

QuadCurve2D
protected QuadCurve2D()This is an abstract class that cannot be instantiated directly. Typespecific implementation subclasses are available for instantiation and provide a number of formats for storing the information necessary to satisfy the various accessor methods below. Since:
 1.2
 See Also:


Method Details

getX1
public abstract double getX1()Returns the X coordinate of the start point indouble
in precision. Returns:
 the X coordinate of the start point.
 Since:
 1.2

getY1
public abstract double getY1()Returns the Y coordinate of the start point indouble
precision. Returns:
 the Y coordinate of the start point.
 Since:
 1.2

getP1
Returns the start point. Returns:
 a
Point2D
that is the start point of thisQuadCurve2D
.  Since:
 1.2

getCtrlX
public abstract double getCtrlX()Returns the X coordinate of the control point indouble
precision. Returns:
 X coordinate the control point
 Since:
 1.2

getCtrlY
public abstract double getCtrlY()Returns the Y coordinate of the control point indouble
precision. Returns:
 the Y coordinate of the control point.
 Since:
 1.2

getCtrlPt
Returns the control point. Returns:
 a
Point2D
that is the control point of thisPoint2D
.  Since:
 1.2

getX2
public abstract double getX2()Returns the X coordinate of the end point indouble
precision. Returns:
 the x coordinate of the end point.
 Since:
 1.2

getY2
public abstract double getY2()Returns the Y coordinate of the end point indouble
precision. Returns:
 the Y coordinate of the end point.
 Since:
 1.2

getP2
Returns the end point. Returns:
 a
Point
object that is the end point of thisPoint2D
.  Since:
 1.2

setCurve
public abstract void setCurve(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Sets the location of the end points and control point of this curve to the specifieddouble
coordinates. Parameters:
x1
 the X coordinate of the start pointy1
 the Y coordinate of the start pointctrlx
 the X coordinate of the control pointctrly
 the Y coordinate of the control pointx2
 the X coordinate of the end pointy2
 the Y coordinate of the end point Since:
 1.2

setCurve
public void setCurve(double[] coords, int offset) Sets the location of the end points and control points of thisQuadCurve2D
to thedouble
coordinates at the specified offset in the specified array. Parameters:
coords
 the array containing coordinate valuesoffset
 the index into the array from which to start getting the coordinate values and assigning them to thisQuadCurve2D
 Since:
 1.2

setCurve

setCurve
Sets the location of the end points and control points of thisQuadCurve2D
to the coordinates of thePoint2D
objects at the specified offset in the specified array. Parameters:
pts
 an array containingPoint2D
that define coordinate valuesoffset
 the index intopts
from which to start getting the coordinate values and assigning them to thisQuadCurve2D
 Since:
 1.2

setCurve
Sets the location of the end points and control point of thisQuadCurve2D
to the same as those in the specifiedQuadCurve2D
. Parameters:
c
 the specifiedQuadCurve2D
 Since:
 1.2

getFlatnessSq
public static double getFlatnessSq(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the indicated control points. Parameters:
x1
 the X coordinate of the start pointy1
 the Y coordinate of the start pointctrlx
 the X coordinate of the control pointctrly
 the Y coordinate of the control pointx2
 the X coordinate of the end pointy2
 the Y coordinate of the end point Returns:
 the square of the flatness of the quadratic curve defined by the specified coordinates.
 Since:
 1.2

getFlatness
public static double getFlatness(double x1, double y1, double ctrlx, double ctrly, double x2, double y2) Returns the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the indicated control points. Parameters:
x1
 the X coordinate of the start pointy1
 the Y coordinate of the start pointctrlx
 the X coordinate of the control pointctrly
 the Y coordinate of the control pointx2
 the X coordinate of the end pointy2
 the Y coordinate of the end point Returns:
 the flatness of the quadratic curve defined by the specified coordinates.
 Since:
 1.2

getFlatnessSq
public static double getFlatnessSq(double[] coords, int offset) Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the control points stored in the indicated array at the indicated index. Parameters:
coords
 an array containing coordinate valuesoffset
 the index intocoords
from which to to start getting the values from the array Returns:
 the flatness of the quadratic curve that is defined by the values in the specified array at the specified index.
 Since:
 1.2

getFlatness
public static double getFlatness(double[] coords, int offset) Returns the flatness, or maximum distance of a control point from the line connecting the end points, of the quadratic curve specified by the control points stored in the indicated array at the indicated index. Parameters:
coords
 an array containing coordinate valuesoffset
 the index intocoords
from which to start getting the coordinate values Returns:
 the flatness of a quadratic curve defined by the specified array at the specified offset.
 Since:
 1.2

getFlatnessSq
public double getFlatnessSq()Returns the square of the flatness, or maximum distance of a control point from the line connecting the end points, of thisQuadCurve2D
. Returns:
 the square of the flatness of this
QuadCurve2D
.  Since:
 1.2

getFlatness
public double getFlatness()Returns the flatness, or maximum distance of a control point from the line connecting the end points, of thisQuadCurve2D
. Returns:
 the flatness of this
QuadCurve2D
.  Since:
 1.2

subdivide
Subdivides thisQuadCurve2D
and stores the resulting two subdivided curves into theleft
andright
curve parameters. Either or both of theleft
andright
objects can be the same as thisQuadCurve2D
ornull
. Parameters:
left
 theQuadCurve2D
object for storing the left or first half of the subdivided curveright
 theQuadCurve2D
object for storing the right or second half of the subdivided curve Since:
 1.2

subdivide
Subdivides the quadratic curve specified by thesrc
parameter and stores the resulting two subdivided curves into theleft
andright
curve parameters. Either or both of theleft
andright
objects can be the same as thesrc
object ornull
. Parameters:
src
 the quadratic curve to be subdividedleft
 theQuadCurve2D
object for storing the left or first half of the subdivided curveright
 theQuadCurve2D
object for storing the right or second half of the subdivided curve Since:
 1.2

subdivide
public static void subdivide(double[] src, int srcoff, double[] left, int leftoff, double[] right, int rightoff) Subdivides the quadratic curve specified by the coordinates stored in thesrc
array at indicessrcoff
throughsrcoff
+ 5 and stores the resulting two subdivided curves into the two result arrays at the corresponding indices. Either or both of theleft
andright
arrays can benull
or a reference to the same array and offset as thesrc
array. Note that the last point in the first subdivided curve is the same as the first point in the second subdivided curve. Thus, it is possible to pass the same array forleft
andright
and to use offsets such thatrightoff
equalsleftoff
+ 4 in order to avoid allocating extra storage for this common point. Parameters:
src
 the array holding the coordinates for the source curvesrcoff
 the offset into the array of the beginning of the the 6 source coordinatesleft
 the array for storing the coordinates for the first half of the subdivided curveleftoff
 the offset into the array of the beginning of the the 6 left coordinatesright
 the array for storing the coordinates for the second half of the subdivided curverightoff
 the offset into the array of the beginning of the the 6 right coordinates Since:
 1.2

solveQuadratic
public static int solveQuadratic(double[] eqn) Solves the quadratic whose coefficients are in theeqn
array and places the noncomplex roots back into the same array, returning the number of roots. The quadratic solved is represented by the equation:eqn = {C, B, A}; ax^2 + bx + c = 0
A return value of1
is used to distinguish a constant equation, which might be always 0 or never 0, from an equation that has no zeroes. Parameters:
eqn
 the array that contains the quadratic coefficients Returns:
 the number of roots, or
1
if the equation is a constant  Since:
 1.2

solveQuadratic
public static int solveQuadratic(double[] eqn, double[] res) Solves the quadratic whose coefficients are in theeqn
array and places the noncomplex roots into theres
array, returning the number of roots. The quadratic solved is represented by the equation:eqn = {C, B, A}; ax^2 + bx + c = 0
A return value of1
is used to distinguish a constant equation, which might be always 0 or never 0, from an equation that has no zeroes. Parameters:
eqn
 the specified array of coefficients to use to solve the quadratic equationres
 the array that contains the noncomplex roots resulting from the solution of the quadratic equation Returns:
 the number of roots, or
1
if the equation is a constant.  Since:
 1.3

contains
public boolean contains(double x, double y) Tests if the specified coordinates are inside the boundary of theShape
, as described by the definition of insideness. 
contains
Tests if a specifiedPoint2D
is inside the boundary of theShape
, as described by the definition of insideness. 
intersects
public boolean intersects(double x, double y, double w, double h) Tests if the interior of theShape
intersects the interior of a specified rectangular area. The rectangular area is considered to intersect theShape
if any point is contained in both the interior of theShape
and the specified rectangular area.The
Shape.intersects()
method allows aShape
implementation to conservatively returntrue
when:
there is a high probability that the rectangular area and the
Shape
intersect, but  the calculations to accurately determine this intersection are prohibitively expensive.
Shapes
this method might returntrue
even though the rectangular area does not intersect theShape
. TheArea
class performs more accurate computations of geometric intersection than mostShape
objects and therefore can be used if a more precise answer is required. Specified by:
intersects
in interfaceShape
 Parameters:
x
 the X coordinate of the upperleft corner of the specified rectangular areay
 the Y coordinate of the upperleft corner of the specified rectangular areaw
 the width of the specified rectangular areah
 the height of the specified rectangular area Returns:
true
if the interior of theShape
and the interior of the rectangular area intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform;false
otherwise. Since:
 1.2
 See Also:

there is a high probability that the rectangular area and the

intersects
Tests if the interior of theShape
intersects the interior of a specifiedRectangle2D
. TheShape.intersects()
method allows aShape
implementation to conservatively returntrue
when:
there is a high probability that the
Rectangle2D
and theShape
intersect, but  the calculations to accurately determine this intersection are prohibitively expensive.
Shapes
this method might returntrue
even though theRectangle2D
does not intersect theShape
. TheArea
class performs more accurate computations of geometric intersection than mostShape
objects and therefore can be used if a more precise answer is required. Specified by:
intersects
in interfaceShape
 Parameters:
r
 the specifiedRectangle2D
 Returns:
true
if the interior of theShape
and the interior of the specifiedRectangle2D
intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform;false
otherwise. Since:
 1.2
 See Also:

there is a high probability that the

contains
public boolean contains(double x, double y, double w, double h) Tests if the interior of theShape
entirely contains the specified rectangular area. All coordinates that lie inside the rectangular area must lie within theShape
for the entire rectangular area to be considered contained within theShape
.The
Shape.contains()
method allows aShape
implementation to conservatively returnfalse
when:
the
intersect
method returnstrue
and 
the calculations to determine whether or not the
Shape
entirely contains the rectangular area are prohibitively expensive.
Shapes
this method might returnfalse
even though theShape
contains the rectangular area. TheArea
class performs more accurate geometric computations than mostShape
objects and therefore can be used if a more precise answer is required. Specified by:
contains
in interfaceShape
 Parameters:
x
 the X coordinate of the upperleft corner of the specified rectangular areay
 the Y coordinate of the upperleft corner of the specified rectangular areaw
 the width of the specified rectangular areah
 the height of the specified rectangular area Returns:
true
if the interior of theShape
entirely contains the specified rectangular area;false
otherwise or, if theShape
contains the rectangular area and theintersects
method returnstrue
and the containment calculations would be too expensive to perform. Since:
 1.2
 See Also:

the

contains
Tests if the interior of theShape
entirely contains the specifiedRectangle2D
. TheShape.contains()
method allows aShape
implementation to conservatively returnfalse
when:
the
intersect
method returnstrue
and 
the calculations to determine whether or not the
Shape
entirely contains theRectangle2D
are prohibitively expensive.
Shapes
this method might returnfalse
even though theShape
contains theRectangle2D
. TheArea
class performs more accurate geometric computations than mostShape
objects and therefore can be used if a more precise answer is required. Specified by:
contains
in interfaceShape
 Parameters:
r
 The specifiedRectangle2D
 Returns:
true
if the interior of theShape
entirely contains theRectangle2D
;false
otherwise or, if theShape
contains theRectangle2D
and theintersects
method returnstrue
and the containment calculations would be too expensive to perform. Since:
 1.2
 See Also:

the

getBounds2D
Returns a high precision and more accurate bounding box of theShape
than thegetBounds
method. Note that there is no guarantee that the returnedRectangle2D
is the smallest bounding box that encloses theShape
, only that theShape
lies entirely within the indicatedRectangle2D
. The bounding box returned by this method is usually tighter than that returned by thegetBounds
method and never fails due to overflow problems since the return value can be an instance of theRectangle2D
that uses double precision values to store the dimensions.Note that the definition of insideness can lead to situations where points on the defining outline of the
shape
may not be considered contained in the returnedbounds
object, but only in cases where those points are also not considered contained in the originalshape
.If a
point
is inside theshape
according to thecontains(point)
method, then it must be inside the returnedRectangle2D
bounds object according to thecontains(point)
method of thebounds
. Specifically:shape.contains(p)
requiresbounds.contains(p)
If a
point
is not inside theshape
, then it might still be contained in thebounds
object:bounds.contains(p)
does not implyshape.contains(p)
 Specified by:
getBounds2D
in interfaceShape
 Returns:
 an instance of
Rectangle2D
that is a highprecision bounding box of theShape
.  Since:
 1.2
 See Also:

getBounds
Returns an integerRectangle
that completely encloses theShape
. Note that there is no guarantee that the returnedRectangle
is the smallest bounding box that encloses theShape
, only that theShape
lies entirely within the indicatedRectangle
. The returnedRectangle
might also fail to completely enclose theShape
if theShape
overflows the limited range of the integer data type. ThegetBounds2D
method generally returns a tighter bounding box due to its greater flexibility in representation.Note that the definition of insideness can lead to situations where points on the defining outline of the
shape
may not be considered contained in the returnedbounds
object, but only in cases where those points are also not considered contained in the originalshape
.If a
point
is inside theshape
according to thecontains(point)
method, then it must be inside the returnedRectangle
bounds object according to thecontains(point)
method of thebounds
. Specifically:shape.contains(x,y)
requiresbounds.contains(x,y)
If a
point
is not inside theshape
, then it might still be contained in thebounds
object:bounds.contains(x,y)
does not implyshape.contains(x,y)

getPathIterator
Returns an iteration object that defines the boundary of the shape of thisQuadCurve2D
. The iterator for this class is not multithreaded safe, which means that thisQuadCurve2D
class does not guarantee that modifications to the geometry of thisQuadCurve2D
object do not affect any iterations of that geometry that are already in process. Specified by:
getPathIterator
in interfaceShape
 Parameters:
at
 an optionalAffineTransform
to apply to the shape boundary Returns:
 a
PathIterator
object that defines the boundary of the shape.  Since:
 1.2

getPathIterator
Returns an iteration object that defines the boundary of the flattened shape of thisQuadCurve2D
. The iterator for this class is not multithreaded safe, which means that thisQuadCurve2D
class does not guarantee that modifications to the geometry of thisQuadCurve2D
object do not affect any iterations of that geometry that are already in process. Specified by:
getPathIterator
in interfaceShape
 Parameters:
at
 an optionalAffineTransform
to apply to the boundary of the shapeflatness
 the maximum distance that the control points for a subdivided curve can be with respect to a line connecting the end points of this curve before this curve is replaced by a straight line connecting the end points. Returns:
 a
PathIterator
object that defines the flattened boundary of the shape.  Since:
 1.2

clone
Creates a new object of the same class and with the same contents as this object. Overrides:
clone
in classObject
 Returns:
 a clone of this instance.
 Throws:
OutOfMemoryError
 if there is not enough memory. Since:
 1.2
 See Also:
