Version of circle code specialized on double.

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

@@ -0,0 +1,65 @@
+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import pythagoras.util.Platform;
+
+/**
+ * Provides most of the implementation of {@link ICircle}, obtaining only the location and radius
+ * from the derived class.
+ */
+public abstract class AbstractCircle implements ICircle
+{
+    @Override // from ICircle
+    public boolean intersects (ICircle c) {
+        double maxDist = radius() + c.radius();
+        return Points.distanceSq(x(), y(), c.x(), c.y()) < (maxDist * maxDist);
+    }
+
+    @Override // from ICircle
+    public boolean contains (IPoint p) {
+        double r = radius();
+        return Points.distanceSq(x(), y(), p.x(), p.y()) < r * r;
+    }
+
+    @Override // from ICircle
+    public boolean contains (double x, double y) {
+        double r = radius();
+        return Points.distanceSq(x(), y(), x, y) < r * r;
+    }
+
+    @Override // from ICircle
+    public Circle offset (double x, double y) {
+        return new Circle(x() + x, y() + y, radius());
+    }
+
+    @Override // from ICircle
+    public Circle offset (double x, double y, Circle result) {
+        result.set(x() + x, y() + y, radius());
+        return result;
+    }
+
+    @Override // from ICircle
+    public Circle clone () {
+        return new Circle(this);
+    }
+
+    @Override
+    public boolean equals (Object obj) {
+        if (obj == this) {
+            return true;
+        }
+        if (obj instanceof AbstractCircle) {
+            AbstractCircle c = (AbstractCircle)obj;
+            return x() == c.x() && y() == c.y() && radius() == c.radius();
+        }
+        return false;
+    }
+
+    @Override
+    public int hashCode () {
+        return Platform.hashCode(x()) ^ Platform.hashCode(y()) ^ Platform.hashCode(radius());
+    }
+}

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

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+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+import java.io.Serializable;
+
+/**
+ * Represents a circle on a plane.
+ */
+public class Circle extends AbstractCircle implements Serializable
+{
+    /** The x-coordinate of the circle. */
+    public double x;
+
+    /** The y-coordinate of the circle. */
+    public double y;
+
+    /** The radius of the circle. */
+    public double radius;
+
+    /**
+     * Constructs a circle at (0, 0) with radius 0
+     */
+    public Circle () {
+    }
+
+    /**
+     * Constructs a circle with the specified properties
+     */
+    public Circle (double x, double y, double radius) {
+        set(x, y, radius);
+    }
+
+    /**
+     * Constructs a circle with the specified properties
+     */
+    public Circle (IPoint p, double radius) {
+        this(p.x(), p.y(), radius);
+    }
+
+    /**
+     * Constructs a circle with properties equal to the supplied circle.
+     */
+    public Circle (ICircle c) {
+        this(c.x(), c.y(), c.radius());
+    }
+
+    /** Sets the properties of this circle to be equal to those of the supplied circle.
+     * @return a reference to this this, for chaining. */
+    public Circle set (ICircle c) {
+        return set(c.x(), c.y(), c.radius());
+    }
+
+    /** Sets the properties of this circle to the supplied values.
+     * @return a reference to this this, for chaining. */
+    public Circle set (double x, double y, double radius) {
+        this.x = x;
+        this.y = y;
+        this.radius = radius;
+        return this;
+    }
+
+    @Override
+    public double x () {
+        return x;
+    }
+
+    @Override
+    public double y () {
+        return y;
+    }
+
+    @Override
+    public double radius () {
+        return radius;
+    }
+}

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

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+//
+// Pythagoras - a collection of geometry classes
+// http://github.com/samskivert/pythagoras
+
+package pythagoras.d;
+
+/**
+ * Provides read-only access to a {@link Circle}.
+ */
+public interface ICircle
+{
+    /** Returns this circle's x-coordinate. */
+    double x ();
+
+    /** Returns this circle's y-coordinate. */
+    double y ();
+
+    /** Returns this circle's radius. */
+    double radius ();
+
+    /** Returns true if this circle intersects the supplied circle. */
+    boolean intersects (ICircle c);
+
+    /** Returns true if this circle contains the supplied point. */
+    boolean contains (IPoint p);
+
+    /** Returns true if this circle contains the specified point. */
+    boolean contains (double x, double y);
+
+    /** Translates the circle by the specified offset.
+     * @return a new Circle containing the result. */
+    Circle offset (double x, double y);
+
+    /** Translates the circle by the specified offset and stores the result in the supplied object.
+     * @return a reference to the result, for chaining. */
+    Circle offset (double x, double y, Circle result);
+
+    /** Returns a mutable copy of this circle. */
+    Circle clone ();
+}