Small tidying.

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

@@ -20,12 +20,14 @@ public abstract class AbstractCircle implements ICircle
 
     @Override // from ICircle
     public boolean contains (IPoint p) {
-        return Points.distanceSq(x(), y(), p.x(), p.y()) < radius() * radius();
+        float r = radius();
+        return Points.distanceSq(x(), y(), p.x(), p.y()) < r * r;
     }
 
     @Override // from ICircle
     public boolean contains (float x, float y) {
-        return Points.distanceSq(x(), y(), x, y) < radius() * radius();
+        float r = radius();
+        return Points.distanceSq(x(), y(), x, y) < r * r;
     }
 
     @Override // from ICircle

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

@@ -28,13 +28,11 @@ public interface ICircle
     boolean contains (float x, float y);
 
     /** Translates the circle by the specified offset.
-     * @return a new Circle containing the result.
-     */
+     * @return a new Circle containing the result. */
     Circle offset (float x, float y);
 
     /** Translates the circle by the specified offset and stores the result in the supplied object.
-     * @return a reference to the result, for chaining.
-     */
+     * @return a reference to the result, for chaining. */
     Circle offset (float x, float y, Circle result);
 
     /** Returns a mutable copy of this circle. */