Java java.awt.geom Class QuadCurve2D（JDK8）

Constructor Detail

• QuadCurve2D

  protected QuadCurve2D()

  This is an abstract class that cannot be instantiated directly. Type-specific 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:

  QuadCurve2D.Float, QuadCurve2D.Double

Method Detail

• getX1

  public abstract double getX1()

  Returns the X coordinate of the start point in double 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 in double precision.

  Returns:

  the Y coordinate of the start point.

  Since:

  1.2

• getP1

  public abstract Point2D getP1()

  Returns the start point.

  Returns:

  a Point2D that is the start point of this QuadCurve2D.

  Since:

  1.2

• getCtrlX

  public abstract double getCtrlX()

  Returns the X coordinate of the control point in double precision.

  Returns:

  X coordinate the control point

  Since:

  1.2

• getCtrlY

  public abstract double getCtrlY()

  Returns the Y coordinate of the control point in double precision.

  Returns:

  the Y coordinate of the control point.

  Since:

  1.2

• getCtrlPt

  public abstract Point2D getCtrlPt()

  Returns the control point.

  Returns:

  a Point2D that is the control point of this Point2D.

  Since:

  1.2

• getX2

  public abstract double getX2()

  Returns the X coordinate of the end point in double 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 in double precision.

  Returns:

  the Y coordinate of the end point.

  Since:

  1.2

• getP2

  public abstract Point2D getP2()

  Returns the end point.

  Returns:

  a Point object that is the end point of this Point2D.

  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 specified double coordinates.

  Parameters:

  x1 - the X coordinate of the start point

  y1 - the Y coordinate of the start point

  ctrlx - the X coordinate of the control point

  ctrly - the Y coordinate of the control point

  x2 - the X coordinate of the end point

  y2 - 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 this QuadCurve2D to the double coordinates at the specified offset in the specified array.

  Parameters:

  coords - the array containing coordinate values

  offset - the index into the array from which to start getting the coordinate values and assigning them to this QuadCurve2D

  Since:

  1.2

• setCurve

  public void setCurve(Point2D p1,
                       Point2D cp,
                       Point2D p2)

  Sets the location of the end points and control point of this QuadCurve2D to the specified Point2D coordinates.

  Parameters:

  p1 - the start point

  cp - the control point

  p2 - the end point

  Since:

  1.2

• setCurve

  public void setCurve(Point2D[] pts,
                       int offset)

  Sets the location of the end points and control points of this QuadCurve2D to the coordinates of the Point2D objects at the specified offset in the specified array.

  Parameters:

  pts - an array containing Point2D that define coordinate values

  offset - the index into pts from which to start getting the coordinate values and assigning them to this QuadCurve2D

  Since:

  1.2

• setCurve

  public void setCurve(QuadCurve2D c)

  Sets the location of the end points and control point of this QuadCurve2D to the same as those in the specified QuadCurve2D.

  Parameters:

  c - the specified QuadCurve2D

  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 point

  y1 - the Y coordinate of the start point

  ctrlx - the X coordinate of the control point

  ctrly - the Y coordinate of the control point

  x2 - the X coordinate of the end point

  y2 - 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 point

  y1 - the Y coordinate of the start point

  ctrlx - the X coordinate of the control point

  ctrly - the Y coordinate of the control point

  x2 - the X coordinate of the end point

  y2 - 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 values

  offset - the index into coords 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 values

  offset - the index into coords 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 this QuadCurve2D.

  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 this QuadCurve2D.

  Returns:

  the flatness of this QuadCurve2D.

  Since:

  1.2

• subdivide

  public void subdivide(QuadCurve2D left,
                        QuadCurve2D right)

  Subdivides this QuadCurve2D and stores the resulting two subdivided curves into the left and right curve parameters. Either or both of the left and right objects can be the same as this QuadCurve2D or null.

  Parameters:

  left - the QuadCurve2D object for storing the left or first half of the subdivided curve

  right - the QuadCurve2D object for storing the right or second half of the subdivided curve

  Since:

  1.2

• subdivide

  public static void subdivide(QuadCurve2D src,
                               QuadCurve2D left,
                               QuadCurve2D right)

  Subdivides the quadratic curve specified by the src parameter and stores the resulting two subdivided curves into the left and right curve parameters. Either or both of the left and right objects can be the same as the src object or null.

  Parameters:

  src - the quadratic curve to be subdivided

  left - the QuadCurve2D object for storing the left or first half of the subdivided curve

  right - the QuadCurve2D 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 the src array at indices srcoff through srcoff + 5 and stores the resulting two subdivided curves into the two result arrays at the corresponding indices. Either or both of the left and right arrays can be null or a reference to the same array and offset as the src 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 for left and right and to use offsets such that rightoff equals leftoff + 4 in order to avoid allocating extra storage for this common point.

  Parameters:

  src - the array holding the coordinates for the source curve

  srcoff - the offset into the array of the beginning of the the 6 source coordinates

  left - the array for storing the coordinates for the first half of the subdivided curve

  leftoff - the offset into the array of the beginning of the the 6 left coordinates

  right - the array for storing the coordinates for the second half of the subdivided curve

  rightoff - 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 the eqn array and places the non-complex 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 of -1 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 the eqn array and places the non-complex roots into the res 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 of -1 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 equation

  res - the array that contains the non-complex 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 the Shape, as described by the definition of insideness.

  Specified by:

  contains in interface Shape

  Parameters:

  x - the specified X coordinate to be tested

  y - the specified Y coordinate to be tested

  Returns:

  true if the specified coordinates are inside the Shape boundary; false otherwise.

  Since:

  1.2

• contains

  public boolean contains(Point2D p)

  Tests if a specified Point2D is inside the boundary of the Shape, as described by the definition of insideness.

  Specified by:

  contains in interface Shape

  Parameters:

  p - the specified Point2D to be tested

  Returns:

  true if the specified Point2D is inside the boundary of the Shape; false otherwise.

  Since:

  1.2

• intersects

  public boolean intersects(double x,
                            double y,
                            double w,
                            double h)

  Tests if the interior of the Shape intersects the interior of a specified rectangular area. The rectangular area is considered to intersect the Shape if any point is contained in both the interior of the Shape and the specified rectangular area.

  The Shape.intersects() method allows a Shape implementation to conservatively return true 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.

  This means that for some Shapes this method might return true even though the rectangular area does not intersect the Shape. The Area class performs more accurate computations of geometric intersection than most Shape objects and therefore can be used if a more precise answer is required.

  Specified by:

  intersects in interface Shape

  Parameters:

  x - the X coordinate of the upper-left corner of the specified rectangular area

  y - the Y coordinate of the upper-left corner of the specified rectangular area

  w - the width of the specified rectangular area

  h - the height of the specified rectangular area

  Returns:

  true if the interior of the Shape 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:

  Area

• intersects

  public boolean intersects(Rectangle2D r)

  Tests if the interior of the Shape intersects the interior of a specified Rectangle2D. The Shape.intersects() method allows a Shape implementation to conservatively return true when:

  • there is a high probability that the Rectangle2D and the Shape intersect, but
  • the calculations to accurately determine this intersection are prohibitively expensive.

  This means that for some Shapes this method might return true even though the Rectangle2D does not intersect the Shape. The Area class performs more accurate computations of geometric intersection than most Shape objects and therefore can be used if a more precise answer is required.

  Specified by:

  intersects in interface Shape

  Parameters:

  r - the specified Rectangle2D

  Returns:

  true if the interior of the Shape and the interior of the specified Rectangle2D intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform; false otherwise.

  Since:

  1.2

  See Also:

  Shape.intersects(double, double, double, double)

• contains

  public boolean contains(double x,
                          double y,
                          double w,
                          double h)

  Tests if the interior of the Shape entirely contains the specified rectangular area. All coordinates that lie inside the rectangular area must lie within the Shape for the entire rectangular area to be considered contained within the Shape.

  The Shape.contains() method allows a Shape implementation to conservatively return false when:

  • the intersect method returns true and
  • the calculations to determine whether or not the Shape entirely contains the rectangular area are prohibitively expensive.

  This means that for some Shapes this method might return false even though the Shape contains the rectangular area. The Area class performs more accurate geometric computations than most Shape objects and therefore can be used if a more precise answer is required.

  Specified by:

  contains in interface Shape

  Parameters:

  x - the X coordinate of the upper-left corner of the specified rectangular area

  y - the Y coordinate of the upper-left corner of the specified rectangular area

  w - the width of the specified rectangular area

  h - the height of the specified rectangular area

  Returns:

  true if the interior of the Shape entirely contains the specified rectangular area; false otherwise or, if the Shape contains the rectangular area and the intersects method returns true and the containment calculations would be too expensive to perform.

  Since:

  1.2

  See Also:

  Area, Shape.intersects(double, double, double, double)

• contains

  public boolean contains(Rectangle2D r)

  Tests if the interior of the Shape entirely contains the specified Rectangle2D. The Shape.contains() method allows a Shape implementation to conservatively return false when:

  • the intersect method returns true and
  • the calculations to determine whether or not the Shape entirely contains the Rectangle2D are prohibitively expensive.

  This means that for some Shapes this method might return false even though the Shape contains the Rectangle2D. The Area class performs more accurate geometric computations than most Shape objects and therefore can be used if a more precise answer is required.

  Specified by:

  contains in interface Shape

  Parameters:

  r - The specified Rectangle2D

  Returns:

  true if the interior of the Shape entirely contains the Rectangle2D; false otherwise or, if the Shape contains the Rectangle2D and the intersects method returns true and the containment calculations would be too expensive to perform.

  Since:

  1.2

  See Also:

  Shape.contains(double, double, double, double)

• getBounds

  public Rectangle getBounds()

  Returns an integer Rectangle that completely encloses the Shape. Note that there is no guarantee that the returned Rectangle is the smallest bounding box that encloses the Shape, only that the Shape lies entirely within the indicated Rectangle. The returned Rectangle might also fail to completely enclose the Shape if the Shape overflows the limited range of the integer data type. The getBounds2D 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 returned bounds object, but only in cases where those points are also not considered contained in the original shape.

  If a point is inside the shape according to the contains(point) method, then it must be inside the returned Rectangle bounds object according to the contains(point) method of the bounds. Specifically:

  shape.contains(x,y) requires bounds.contains(x,y)

  If a point is not inside the shape, then it might still be contained in the bounds object:

  bounds.contains(x,y) does not imply shape.contains(x,y)

  Specified by:

  getBounds in interface Shape

  Returns:

  an integer Rectangle that completely encloses the Shape.

  Since:

  1.2

  See Also:

  Shape.getBounds2D()

• getPathIterator

  public PathIterator getPathIterator(AffineTransform at)

  Returns an iteration object that defines the boundary of the shape of this QuadCurve2D. The iterator for this class is not multi-threaded safe, which means that this QuadCurve2D class does not guarantee that modifications to the geometry of this QuadCurve2D object do not affect any iterations of that geometry that are already in process.

  Specified by:

  getPathIterator in interface Shape

  Parameters:

  at - an optional AffineTransform to apply to the shape boundary

  Returns:

  a PathIterator object that defines the boundary of the shape.

  Since:

  1.2

• getPathIterator

  public PathIterator getPathIterator(AffineTransform at,
                                      double flatness)

  Returns an iteration object that defines the boundary of the flattened shape of this QuadCurve2D. The iterator for this class is not multi-threaded safe, which means that this QuadCurve2D class does not guarantee that modifications to the geometry of this QuadCurve2D object do not affect any iterations of that geometry that are already in process.

  Specified by:

  getPathIterator in interface Shape

  Parameters:

  at - an optional AffineTransform to apply to the boundary of the shape

  flatness - 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

  public Object clone()

  Creates a new object of the same class and with the same contents as this object.

  Overrides:

  clone in class Object

  Returns:

  a clone of this instance.

  Throws:

  OutOfMemoryError - if there is not enough memory.

  Since:

  1.2

  See Also:

  Cloneable