Take XY wherever we took IPoint.

Be lenient in what you accept, strict in what you produce.

src/main/java/pythagoras/d/AbstractCircle.java

@@ -19,7 +19,7 @@ public abstract class AbstractCircle implements ICircle
     }
 
     @Override // from ICircle
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         double r = radius();
         return Points.distanceSq(x(), y(), p.x(), p.y()) < r * r;
     }

src/main/java/pythagoras/d/AbstractCubicCurve.java

@@ -72,7 +72,7 @@ public abstract class AbstractCubicCurve implements ICubicCurve
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/AbstractLine.java

@@ -38,7 +38,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public double pointLineDistSq (IPoint p) {
+    public double pointLineDistSq (XY p) {
         return Lines.pointLineDistSq(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -48,7 +48,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public double pointLineDist (IPoint p) {
+    public double pointLineDist (XY p) {
         return Lines.pointLineDist(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -58,7 +58,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public double pointSegDistSq (IPoint p) {
+    public double pointSegDistSq (XY p) {
         return Lines.pointSegDistSq(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -68,7 +68,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public double pointSegDist (IPoint p) {
+    public double pointSegDist (XY p) {
         return Lines.pointSegDist(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -78,7 +78,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public int relativeCCW (IPoint p) {
+    public int relativeCCW (XY p) {
         return Lines.relativeCCW(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -98,7 +98,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint point) {
+    public boolean contains (XY point) {
         return false;
     }
 

src/main/java/pythagoras/d/AbstractPoint.java

@@ -18,7 +18,7 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override // from IPoint
-    public double distanceSq (IPoint p) {
+    public double distanceSq (XY p) {
         return Points.distanceSq(x(), y(), p.x(), p.y());
     }
 
@@ -28,12 +28,12 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override // from IPoint
-    public double distance (IPoint p) {
+    public double distance (XY p) {
         return Points.distance(x(), y(), p.x(), p.y());
     }
 
     @Override // from interface IPoint
-    public double direction (IPoint other) {
+    public double direction (XY other) {
         return Math.atan2(other.y() - y(), other.x() - x());
     }
 
@@ -68,7 +68,7 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override
-    public Point subtract (IPoint other, Point result) {
+    public Point subtract (XY other, Point result) {
         return subtract(other.x(), other.y(), result);
     }
 

src/main/java/pythagoras/d/AbstractQuadCurve.java

@@ -64,7 +64,7 @@ public abstract class AbstractQuadCurve implements IQuadCurve
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/AbstractRectangle.java

@@ -90,7 +90,7 @@ public abstract class AbstractRectangle extends RectangularShape implements IRec
     }
 
     @Override // from interface IRectangle
-    public int outcode (IPoint p) {
+    public int outcode (XY p) {
         return outcode(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/Arc.java

@@ -138,7 +138,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the location, size, angular extents, and closure type of this arc to the specified
      * values.
      */
-    public void setArc (IPoint point, IDimension size, double start, double extent, int type) {
+    public void setArc (XY point, IDimension size, double start, double extent, int type) {
         setArc(point.x(), point.y(), size.width(), size.height(), start, extent, type);
     }
 
@@ -172,7 +172,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the location, size, angular extents, and closure type of this arc based on the
      * specified values.
      */
-    public void setArcByTangent (IPoint p1, IPoint p2, IPoint p3, double radius) {
+    public void setArcByTangent (XY p1, XY p2, XY p3, double radius) {
         // use simple geometric calculations of arc center, radius and angles by tangents
         double a1 = -Math.atan2(p1.y() - p2.y(), p1.x() - p2.x());
         double a2 = -Math.atan2(p3.y() - p2.y(), p3.x() - p2.x());
@@ -195,7 +195,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the starting angle of this arc to the angle defined by the supplied point relative to
      * the center of this arc.
      */
-    public void setAngleStart (IPoint point) {
+    public void setAngleStart (XY point) {
         double angle = Math.atan2(point.y() - centerY(), point.x() - centerX());
         setAngleStart(normAngle(-Math.toDegrees(angle)));
     }
@@ -227,7 +227,7 @@ public class Arc extends AbstractArc implements Serializable
      * point relative to the arc's center. The arc will always be non-empty and extend
      * counterclockwise from the first point around to the second point.
      */
-    public void setAngles (IPoint p1, IPoint p2) {
+    public void setAngles (XY p1, XY p2) {
         setAngles(p1.x(), p1.y(), p2.x(), p2.y());
     }
 

src/main/java/pythagoras/d/Area.java

@@ -217,7 +217,7 @@ public class Area implements IShape, Cloneable
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/Circle.java

@@ -36,7 +36,7 @@ public class Circle extends AbstractCircle implements Serializable
     /**
      * Constructs a circle with the specified properties
      */
-    public Circle (IPoint p, double radius) {
+    public Circle (XY p, double radius) {
         this(p.x(), p.y(), radius);
     }
 

src/main/java/pythagoras/d/CubicCurve.java

@@ -67,7 +67,7 @@ public class CubicCurve extends AbstractCubicCurve implements Serializable
     /**
      * Configures the start, control and end points for this curve.
      */
-    public void setCurve (IPoint p1, IPoint cp1, IPoint cp2, IPoint p2) {
+    public void setCurve (XY p1, XY cp1, XY cp2, XY p2) {
         setCurve(p1.x(), p1.y(), cp1.x(), cp1.y(),
                  cp2.x(), cp2.y(), p2.x(), p2.y());
     }
@@ -85,7 +85,7 @@ public class CubicCurve extends AbstractCubicCurve implements Serializable
      * Configures the start, control and end points for this curve, using the values at the
      * specified offset in the {@code points} array.
      */
-    public void setCurve (IPoint[] points, int offset) {
+    public void setCurve (XY[] points, int offset) {
         setCurve(points[offset + 0].x(), points[offset + 0].y(),
                  points[offset + 1].x(), points[offset + 1].y(),
                  points[offset + 2].x(), points[offset + 2].y(),

src/main/java/pythagoras/d/ICircle.java

@@ -22,7 +22,7 @@ public interface ICircle
     boolean intersects (ICircle c);
 
     /** Returns true if this circle contains the supplied point. */
-    boolean contains (IPoint p);
+    boolean contains (XY p);
 
     /** Returns true if this circle contains the specified point. */
     boolean contains (double x, double y);

src/main/java/pythagoras/d/ILine.java

@@ -41,32 +41,32 @@ public interface ILine extends IShape, Cloneable
 
     /** Returns the square of the distance from the supplied point to the line defined by this line
      * segment. */
-    double pointLineDistSq (IPoint p);
+    double pointLineDistSq (XY p);
 
     /** Returns the distance from the specified point to the line defined by this line segment. */
     double pointLineDist (double px, double py);
 
     /** Returns the distance from the supplied point to the line defined by this line segment. */
-    double pointLineDist (IPoint p);
+    double pointLineDist (XY p);
 
     /** Returns the square of the distance from the specified point this line segment. */
     double pointSegDistSq (double px, double py);
 
     /** Returns the square of the distance from the supplied point this line segment. */
-    double pointSegDistSq (IPoint p);
+    double pointSegDistSq (XY p);
 
     /** Returns the distance from the specified point this line segment. */
     double pointSegDist (double px, double py);
 
     /** Returns the distance from the supplied point this line segment. */
-    double pointSegDist (IPoint p);
+    double pointSegDist (XY p);
 
     /** Returns an indicator of where the specified point (px,py) lies with respect to this line
      * segment. */
     int relativeCCW (double px, double py);
 
     /** Returns an indicator of where the specified point lies with respect to this line segment. */
-    int relativeCCW (IPoint p);
+    int relativeCCW (XY p);
 
     /** Returns a mutable copy of this line. */
     Line clone ();

src/main/java/pythagoras/d/IPoint.java

@@ -13,17 +13,17 @@ public interface IPoint extends XY, Cloneable
     double distanceSq (double px, double py);
 
     /** Returns the squared Euclidian distance between this point and the supplied point. */
-    double distanceSq (IPoint p);
+    double distanceSq (XY p);
 
     /** Returns the Euclidian distance between this point and the specified point. */
     double distance (double px, double py);
 
     /** Returns the Euclidian distance between this point and the supplied point. */
-    double distance (IPoint p);
+    double distance (XY p);
 
     /** Returns the angle (in radians) of the vector starting at this point and ending at the
      * supplied other point. */
-    double direction (IPoint other);
+    double direction (XY other);
 
     /** Multiplies this point by a scale factor.
      * @return a new point containing the result. */
@@ -51,7 +51,7 @@ public interface IPoint extends XY, Cloneable
 
     /** Subtracts the supplied point from {@code this} and stores the result in {@code result}.
      * @return a reference to the result, for chaining. */
-    Point subtract (IPoint other, Point result);
+    Point subtract (XY other, Point result);
 
     /** Rotates this point around the origin by the specified angle.
      * @return a new point containing the result. */

src/main/java/pythagoras/d/IRectangle.java

@@ -61,7 +61,7 @@ public interface IRectangle extends IRectangularShape, Cloneable
 
     /** Returns a set of flags indicating where the supplied point lies in relation to the bounds of
      * this rectangle. See {@link #OUT_LEFT}, etc. */
-    int outcode (IPoint point);
+    int outcode (XY point);
 
     /** Returns a mutable copy of this rectangle. */
     Rectangle clone ();

src/main/java/pythagoras/d/IShape.java

@@ -16,7 +16,7 @@ public interface IShape
     boolean contains (double x, double y);
 
     /** Returns true if this shape contains the supplied point. */
-    boolean contains (IPoint point);
+    boolean contains (XY point);
 
     /** Returns true if this shape completely contains the specified rectangle. */
     boolean contains (double x, double y, double width, double height);

src/main/java/pythagoras/d/Line.java

@@ -39,7 +39,7 @@ public class Line extends AbstractLine implements Serializable
     /**
      * Creates a line from p1 to p2.
      */
-    public Line (IPoint p1, IPoint p2) {
+    public Line (XY p1, XY p2) {
         setLine(p1, p2);
     }
 
@@ -56,7 +56,7 @@ public class Line extends AbstractLine implements Serializable
     /**
      * Sets the start and end of this line to the specified points.
      */
-    public void setLine (IPoint p1, IPoint p2) {
+    public void setLine (XY p1, XY p2) {
         setLine(p1.x(), p1.y(), p2.x(), p2.y());
     }
 

src/main/java/pythagoras/d/Path.java

@@ -226,7 +226,7 @@ public final class Path implements IShape, Cloneable
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/Point.java

@@ -33,13 +33,13 @@ public class Point extends AbstractPoint implements Serializable
     /**
      * Constructs a point with coordinates equal to the supplied point.
      */
-    public Point (IPoint p) {
+    public Point (XY p) {
         set(p.x(), p.y());
     }
 
     /** Sets the coordinates of this point to be equal to those of the supplied point.
      * @return a reference to this this, for chaining. */
-    public Point set (IPoint p) {
+    public Point set (XY p) {
         return set(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/QuadCurve.java

@@ -57,7 +57,7 @@ public class QuadCurve extends AbstractQuadCurve implements Serializable
     /**
      * Configures the start, control, and end points for this curve.
      */
-    public void setCurve (IPoint p1, IPoint cp, IPoint p2) {
+    public void setCurve (XY p1, XY cp, XY p2) {
         setCurve(p1.x(), p1.y(), cp.x(), cp.y(), p2.x(), p2.y());
     }
 
@@ -75,7 +75,7 @@ public class QuadCurve extends AbstractQuadCurve implements Serializable
      * Configures the start, control, and end points for this curve, using the values at the
      * specified offset in the {@code points} array.
      */
-    public void setCurve (IPoint[] points, int offset) {
+    public void setCurve (XY[] points, int offset) {
         setCurve(points[offset + 0].x(), points[offset + 0].y(),
                  points[offset + 1].x(), points[offset + 1].y(),
                  points[offset + 2].x(), points[offset + 2].y());

src/main/java/pythagoras/d/Rectangle.java

@@ -32,7 +32,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Constructs a rectangle with the supplied upper-left corner and dimensions (0,0).
      */
-    public Rectangle (IPoint p) {
+    public Rectangle (XY p) {
         setBounds(p.x(), p.y(), 0, 0);
     }
 
@@ -47,7 +47,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
      * Constructs a rectangle with upper-left corner at the supplied point and with the supplied
      * dimensions.
      */
-    public Rectangle (IPoint p, IDimension d) {
+    public Rectangle (XY p, IDimension d) {
         setBounds(p.x(), p.y(), d.width(), d.height());
     }
 
@@ -76,7 +76,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Sets the upper-left corner of this rectangle to the supplied point.
      */
-    public void setLocation (IPoint p) {
+    public void setLocation (XY p) {
         setLocation(p.x(), p.y());
     }
 
@@ -146,7 +146,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Expands the bounds of this rectangle to contain the supplied point.
      */
-    public void add (IPoint p) {
+    public void add (XY p) {
         add(p.x(), p.y());
     }
 

src/main/java/pythagoras/d/RectangularShape.java

@@ -18,7 +18,7 @@ public abstract class RectangularShape implements IRectangularShape
     /**
      * Sets the location and size of the framing rectangle of this shape to the supplied values.
      */
-    public void setFrame (IPoint loc, IDimension size) {
+    public void setFrame (XY loc, IDimension size) {
         setFrame(loc.x(), loc.y(), size.width(), size.height());
     }
 
@@ -57,7 +57,7 @@ public abstract class RectangularShape implements IRectangularShape
      * Sets the location and size of the framing rectangle of this shape based on the supplied
      * diagonal line.
      */
-    public void setFrameFromDiagonal (IPoint p1, IPoint p2) {
+    public void setFrameFromDiagonal (XY p1, XY p2) {
         setFrameFromDiagonal(p1.x(), p1.y(), p2.x(), p2.y());
     }
 
@@ -76,7 +76,7 @@ public abstract class RectangularShape implements IRectangularShape
      * Sets the location and size of the framing rectangle of this shape based on the supplied
      * center and corner points.
      */
-    public void setFrameFromCenter (IPoint center, IPoint corner) {
+    public void setFrameFromCenter (XY center, XY corner) {
         setFrameFromCenter(center.x(), center.y(), corner.x(), corner.y());
     }
 
@@ -144,7 +144,7 @@ public abstract class RectangularShape implements IRectangularShape
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint point) {
+    public boolean contains (XY point) {
         return contains(point.x(), point.y());
     }
 

src/main/java/pythagoras/d/Vectors.java

@@ -35,7 +35,7 @@ public class Vectors
     /**
      * Creates a vector from {@code from} to {@code to}.
      */
-    public static Vector from (IPoint from, IPoint to) {
+    public static Vector from (XY from, XY to) {
         return new Vector(to.x() - from.x(), to.y() - from.y());
     }
 

src/main/java/pythagoras/f/AbstractCircle.java

@@ -19,7 +19,7 @@ public abstract class AbstractCircle implements ICircle
     }
 
     @Override // from ICircle
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         float r = radius();
         return Points.distanceSq(x(), y(), p.x(), p.y()) < r * r;
     }

src/main/java/pythagoras/f/AbstractCubicCurve.java

@@ -72,7 +72,7 @@ public abstract class AbstractCubicCurve implements ICubicCurve
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/AbstractLine.java

@@ -38,7 +38,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public float pointLineDistSq (IPoint p) {
+    public float pointLineDistSq (XY p) {
         return Lines.pointLineDistSq(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -48,7 +48,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public float pointLineDist (IPoint p) {
+    public float pointLineDist (XY p) {
         return Lines.pointLineDist(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -58,7 +58,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public float pointSegDistSq (IPoint p) {
+    public float pointSegDistSq (XY p) {
         return Lines.pointSegDistSq(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -68,7 +68,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public float pointSegDist (IPoint p) {
+    public float pointSegDist (XY p) {
         return Lines.pointSegDist(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -78,7 +78,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface ILine
-    public int relativeCCW (IPoint p) {
+    public int relativeCCW (XY p) {
         return Lines.relativeCCW(p.x(), p.y(), x1(), y1(), x2(), y2());
     }
 
@@ -98,7 +98,7 @@ public abstract class AbstractLine implements ILine
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint point) {
+    public boolean contains (XY point) {
         return false;
     }
 

src/main/java/pythagoras/f/AbstractPoint.java

@@ -18,7 +18,7 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override // from IPoint
-    public float distanceSq (IPoint p) {
+    public float distanceSq (XY p) {
         return Points.distanceSq(x(), y(), p.x(), p.y());
     }
 
@@ -28,12 +28,12 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override // from IPoint
-    public float distance (IPoint p) {
+    public float distance (XY p) {
         return Points.distance(x(), y(), p.x(), p.y());
     }
 
     @Override // from interface IPoint
-    public float direction (IPoint other) {
+    public float direction (XY other) {
         return FloatMath.atan2(other.y() - y(), other.x() - x());
     }
 
@@ -68,7 +68,7 @@ public abstract class AbstractPoint implements IPoint
     }
 
     @Override
-    public Point subtract (IPoint other, Point result) {
+    public Point subtract (XY other, Point result) {
         return subtract(other.x(), other.y(), result);
     }
 

src/main/java/pythagoras/f/AbstractQuadCurve.java

@@ -64,7 +64,7 @@ public abstract class AbstractQuadCurve implements IQuadCurve
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/AbstractRectangle.java

@@ -90,7 +90,7 @@ public abstract class AbstractRectangle extends RectangularShape implements IRec
     }
 
     @Override // from interface IRectangle
-    public int outcode (IPoint p) {
+    public int outcode (XY p) {
         return outcode(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/Arc.java

@@ -138,7 +138,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the location, size, angular extents, and closure type of this arc to the specified
      * values.
      */
-    public void setArc (IPoint point, IDimension size, float start, float extent, int type) {
+    public void setArc (XY point, IDimension size, float start, float extent, int type) {
         setArc(point.x(), point.y(), size.width(), size.height(), start, extent, type);
     }
 
@@ -172,7 +172,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the location, size, angular extents, and closure type of this arc based on the
      * specified values.
      */
-    public void setArcByTangent (IPoint p1, IPoint p2, IPoint p3, float radius) {
+    public void setArcByTangent (XY p1, XY p2, XY p3, float radius) {
         // use simple geometric calculations of arc center, radius and angles by tangents
         float a1 = -FloatMath.atan2(p1.y() - p2.y(), p1.x() - p2.x());
         float a2 = -FloatMath.atan2(p3.y() - p2.y(), p3.x() - p2.x());
@@ -195,7 +195,7 @@ public class Arc extends AbstractArc implements Serializable
      * Sets the starting angle of this arc to the angle defined by the supplied point relative to
      * the center of this arc.
      */
-    public void setAngleStart (IPoint point) {
+    public void setAngleStart (XY point) {
         float angle = FloatMath.atan2(point.y() - centerY(), point.x() - centerX());
         setAngleStart(normAngle(-FloatMath.toDegrees(angle)));
     }
@@ -227,7 +227,7 @@ public class Arc extends AbstractArc implements Serializable
      * point relative to the arc's center. The arc will always be non-empty and extend
      * counterclockwise from the first point around to the second point.
      */
-    public void setAngles (IPoint p1, IPoint p2) {
+    public void setAngles (XY p1, XY p2) {
         setAngles(p1.x(), p1.y(), p2.x(), p2.y());
     }
 

src/main/java/pythagoras/f/Area.java

@@ -217,7 +217,7 @@ public class Area implements IShape, Cloneable
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/Circle.java

@@ -36,7 +36,7 @@ public class Circle extends AbstractCircle implements Serializable
     /**
      * Constructs a circle with the specified properties
      */
-    public Circle (IPoint p, float radius) {
+    public Circle (XY p, float radius) {
         this(p.x(), p.y(), radius);
     }
 

src/main/java/pythagoras/f/CubicCurve.java

@@ -67,7 +67,7 @@ public class CubicCurve extends AbstractCubicCurve implements Serializable
     /**
      * Configures the start, control and end points for this curve.
      */
-    public void setCurve (IPoint p1, IPoint cp1, IPoint cp2, IPoint p2) {
+    public void setCurve (XY p1, XY cp1, XY cp2, XY p2) {
         setCurve(p1.x(), p1.y(), cp1.x(), cp1.y(),
                  cp2.x(), cp2.y(), p2.x(), p2.y());
     }
@@ -85,7 +85,7 @@ public class CubicCurve extends AbstractCubicCurve implements Serializable
      * Configures the start, control and end points for this curve, using the values at the
      * specified offset in the {@code points} array.
      */
-    public void setCurve (IPoint[] points, int offset) {
+    public void setCurve (XY[] points, int offset) {
         setCurve(points[offset + 0].x(), points[offset + 0].y(),
                  points[offset + 1].x(), points[offset + 1].y(),
                  points[offset + 2].x(), points[offset + 2].y(),

src/main/java/pythagoras/f/ICircle.java

@@ -22,7 +22,7 @@ public interface ICircle
     boolean intersects (ICircle c);
 
     /** Returns true if this circle contains the supplied point. */
-    boolean contains (IPoint p);
+    boolean contains (XY p);
 
     /** Returns true if this circle contains the specified point. */
     boolean contains (float x, float y);

src/main/java/pythagoras/f/ILine.java

@@ -41,32 +41,32 @@ public interface ILine extends IShape, Cloneable
 
     /** Returns the square of the distance from the supplied point to the line defined by this line
      * segment. */
-    float pointLineDistSq (IPoint p);
+    float pointLineDistSq (XY p);
 
     /** Returns the distance from the specified point to the line defined by this line segment. */
     float pointLineDist (float px, float py);
 
     /** Returns the distance from the supplied point to the line defined by this line segment. */
-    float pointLineDist (IPoint p);
+    float pointLineDist (XY p);
 
     /** Returns the square of the distance from the specified point this line segment. */
     float pointSegDistSq (float px, float py);
 
     /** Returns the square of the distance from the supplied point this line segment. */
-    float pointSegDistSq (IPoint p);
+    float pointSegDistSq (XY p);
 
     /** Returns the distance from the specified point this line segment. */
     float pointSegDist (float px, float py);
 
     /** Returns the distance from the supplied point this line segment. */
-    float pointSegDist (IPoint p);
+    float pointSegDist (XY p);
 
     /** Returns an indicator of where the specified point (px,py) lies with respect to this line
      * segment. */
     int relativeCCW (float px, float py);
 
     /** Returns an indicator of where the specified point lies with respect to this line segment. */
-    int relativeCCW (IPoint p);
+    int relativeCCW (XY p);
 
     /** Returns a mutable copy of this line. */
     Line clone ();

src/main/java/pythagoras/f/IPoint.java

@@ -13,17 +13,17 @@ public interface IPoint extends XY, Cloneable
     float distanceSq (float px, float py);
 
     /** Returns the squared Euclidian distance between this point and the supplied point. */
-    float distanceSq (IPoint p);
+    float distanceSq (XY p);
 
     /** Returns the Euclidian distance between this point and the specified point. */
     float distance (float px, float py);
 
     /** Returns the Euclidian distance between this point and the supplied point. */
-    float distance (IPoint p);
+    float distance (XY p);
 
     /** Returns the angle (in radians) of the vector starting at this point and ending at the
      * supplied other point. */
-    float direction (IPoint other);
+    float direction (XY other);
 
     /** Multiplies this point by a scale factor.
      * @return a new point containing the result. */
@@ -51,7 +51,7 @@ public interface IPoint extends XY, Cloneable
 
     /** Subtracts the supplied point from {@code this} and stores the result in {@code result}.
      * @return a reference to the result, for chaining. */
-    Point subtract (IPoint other, Point result);
+    Point subtract (XY other, Point result);
 
     /** Rotates this point around the origin by the specified angle.
      * @return a new point containing the result. */

src/main/java/pythagoras/f/IRectangle.java

@@ -61,7 +61,7 @@ public interface IRectangle extends IRectangularShape, Cloneable
 
     /** Returns a set of flags indicating where the supplied point lies in relation to the bounds of
      * this rectangle. See {@link #OUT_LEFT}, etc. */
-    int outcode (IPoint point);
+    int outcode (XY point);
 
     /** Returns a mutable copy of this rectangle. */
     Rectangle clone ();

src/main/java/pythagoras/f/IShape.java

@@ -16,7 +16,7 @@ public interface IShape
     boolean contains (float x, float y);
 
     /** Returns true if this shape contains the supplied point. */
-    boolean contains (IPoint point);
+    boolean contains (XY point);
 
     /** Returns true if this shape completely contains the specified rectangle. */
     boolean contains (float x, float y, float width, float height);

src/main/java/pythagoras/f/Line.java

@@ -39,7 +39,7 @@ public class Line extends AbstractLine implements Serializable
     /**
      * Creates a line from p1 to p2.
      */
-    public Line (IPoint p1, IPoint p2) {
+    public Line (XY p1, XY p2) {
         setLine(p1, p2);
     }
 
@@ -56,7 +56,7 @@ public class Line extends AbstractLine implements Serializable
     /**
      * Sets the start and end of this line to the specified points.
      */
-    public void setLine (IPoint p1, IPoint p2) {
+    public void setLine (XY p1, XY p2) {
         setLine(p1.x(), p1.y(), p2.x(), p2.y());
     }
 

src/main/java/pythagoras/f/Path.java

@@ -226,7 +226,7 @@ public final class Path implements IShape, Cloneable
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint p) {
+    public boolean contains (XY p) {
         return contains(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/Point.java

@@ -33,13 +33,13 @@ public class Point extends AbstractPoint implements Serializable
     /**
      * Constructs a point with coordinates equal to the supplied point.
      */
-    public Point (IPoint p) {
+    public Point (XY p) {
         set(p.x(), p.y());
     }
 
     /** Sets the coordinates of this point to be equal to those of the supplied point.
      * @return a reference to this this, for chaining. */
-    public Point set (IPoint p) {
+    public Point set (XY p) {
         return set(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/QuadCurve.java

@@ -57,7 +57,7 @@ public class QuadCurve extends AbstractQuadCurve implements Serializable
     /**
      * Configures the start, control, and end points for this curve.
      */
-    public void setCurve (IPoint p1, IPoint cp, IPoint p2) {
+    public void setCurve (XY p1, XY cp, XY p2) {
         setCurve(p1.x(), p1.y(), cp.x(), cp.y(), p2.x(), p2.y());
     }
 
@@ -75,7 +75,7 @@ public class QuadCurve extends AbstractQuadCurve implements Serializable
      * Configures the start, control, and end points for this curve, using the values at the
      * specified offset in the {@code points} array.
      */
-    public void setCurve (IPoint[] points, int offset) {
+    public void setCurve (XY[] points, int offset) {
         setCurve(points[offset + 0].x(), points[offset + 0].y(),
                  points[offset + 1].x(), points[offset + 1].y(),
                  points[offset + 2].x(), points[offset + 2].y());

src/main/java/pythagoras/f/Rectangle.java

@@ -32,7 +32,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Constructs a rectangle with the supplied upper-left corner and dimensions (0,0).
      */
-    public Rectangle (IPoint p) {
+    public Rectangle (XY p) {
         setBounds(p.x(), p.y(), 0, 0);
     }
 
@@ -47,7 +47,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
      * Constructs a rectangle with upper-left corner at the supplied point and with the supplied
      * dimensions.
      */
-    public Rectangle (IPoint p, IDimension d) {
+    public Rectangle (XY p, IDimension d) {
         setBounds(p.x(), p.y(), d.width(), d.height());
     }
 
@@ -76,7 +76,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Sets the upper-left corner of this rectangle to the supplied point.
      */
-    public void setLocation (IPoint p) {
+    public void setLocation (XY p) {
         setLocation(p.x(), p.y());
     }
 
@@ -146,7 +146,7 @@ public class Rectangle extends AbstractRectangle implements Serializable
     /**
      * Expands the bounds of this rectangle to contain the supplied point.
      */
-    public void add (IPoint p) {
+    public void add (XY p) {
         add(p.x(), p.y());
     }
 

src/main/java/pythagoras/f/RectangularShape.java

@@ -18,7 +18,7 @@ public abstract class RectangularShape implements IRectangularShape
     /**
      * Sets the location and size of the framing rectangle of this shape to the supplied values.
      */
-    public void setFrame (IPoint loc, IDimension size) {
+    public void setFrame (XY loc, IDimension size) {
         setFrame(loc.x(), loc.y(), size.width(), size.height());
     }
 
@@ -57,7 +57,7 @@ public abstract class RectangularShape implements IRectangularShape
      * Sets the location and size of the framing rectangle of this shape based on the supplied
      * diagonal line.
      */
-    public void setFrameFromDiagonal (IPoint p1, IPoint p2) {
+    public void setFrameFromDiagonal (XY p1, XY p2) {
         setFrameFromDiagonal(p1.x(), p1.y(), p2.x(), p2.y());
     }
 
@@ -76,7 +76,7 @@ public abstract class RectangularShape implements IRectangularShape
      * Sets the location and size of the framing rectangle of this shape based on the supplied
      * center and corner points.
      */
-    public void setFrameFromCenter (IPoint center, IPoint corner) {
+    public void setFrameFromCenter (XY center, XY corner) {
         setFrameFromCenter(center.x(), center.y(), corner.x(), corner.y());
     }
 
@@ -144,7 +144,7 @@ public abstract class RectangularShape implements IRectangularShape
     }
 
     @Override // from interface IShape
-    public boolean contains (IPoint point) {
+    public boolean contains (XY point) {
         return contains(point.x(), point.y());
     }
 

src/main/java/pythagoras/f/Vectors.java

@@ -35,7 +35,7 @@ public class Vectors
     /**
      * Creates a vector from {@code from} to {@code to}.
      */
-    public static Vector from (IPoint from, IPoint to) {
+    public static Vector from (XY from, XY to) {
         return new Vector(to.x() - from.x(), to.y() - from.y());
     }