Added Transform.transformPoint(Vector), enabled Ray2 transforms.

I've tried to make a useful distinction between Point and Vector, but sometimes
you just want to use a Vector as a Point. I'm not going to add Point3 and try
to push this distinction into the third dimension, so I'll accommodate using
Vector as Point in 2D, and we'll just use Vector3 as a 3D point when needed.

src/main/java/pythagoras/f/AffineTransform.java

@@ -309,6 +309,12 @@ public class AffineTransform extends AbstractTransform
                         (y * m00 - x * m01) * rdet);
     }
 
+    @Override // from Transform
+    public Vector transformPoint (IVector v, Vector into) {
+        float x = v.x(), y = v.y();
+        return into.set(m00*x + m10*y + tx, m01*x + m11*y + ty);
+    }
+
     @Override // from Transform
     public Vector transform (IVector v, Vector into) {
         float x = v.x(), y = v.y();

src/main/java/pythagoras/f/IPlane.java

@@ -32,7 +32,7 @@ public interface IPlane
     //  *
     //  * @return a new plane containing the result.
     //  */
-    // Plane transform (Transform transform);
+    // Plane transform (Transform3D transform);
 
     // /**
     //  * Transforms this plane by the specified transformation, placing the result in the object
@@ -40,7 +40,7 @@ public interface IPlane
     //  *
     //  * @return a reference to the result plane, for chaining.
     //  */
-    // Plane transform (Transform transform, Plane result);
+    // Plane transform (Transform3D transform, Plane result);
 
     /**
      * Negates this plane.

src/main/java/pythagoras/f/IRay2.java

@@ -19,19 +19,19 @@ public interface IRay2
      */
     IVector direction ();
 
-    // /**
-    //  * Transforms this ray.
-    //  *
-    //  * @return a new ray containing the result.
-    //  */
-    // Ray2 transform (Transform2D transform);
+    /**
+     * Transforms this ray.
+     *
+     * @return a new ray containing the result.
+     */
+    Ray2 transform (Transform transform);
 
-    // /**
-    //  * Transforms this ray, placing the result in the object provided.
-    //  *
-    //  * @return a reference to the result ray, for chaining.
-    //  */
-    // Ray2 transform (Transform2D transform, Ray2 result);
+    /**
+     * Transforms this ray, placing the result in the object provided.
+     *
+     * @return a reference to the result ray, for chaining.
+     */
+    Ray2 transform (Transform transform, Ray2 result);
 
     /**
      * Determines whether the ray intersects the specified point.

src/main/java/pythagoras/f/IdentityTransform.java

@@ -86,6 +86,11 @@ public class IdentityTransform extends AbstractTransform
         return into.set(p);
     }
 
+    @Override // from Transform
+    public Vector transformPoint (IVector v, Vector into) {
+        return into.set(v);
+    }
+
     @Override // from Transform
     public Vector transform (IVector v, Vector into) {
         return into.set(v);

src/main/java/pythagoras/f/NonUniformTransform.java

@@ -231,6 +231,11 @@ public class NonUniformTransform extends AbstractTransform
         return Points.inverseTransform(p.x(), p.y(), scaleX, scaleY, rotation, tx, ty, into);
     }
 
+    @Override // from Transform
+    public Vector transformPoint (IVector v, Vector into) {
+        return Vectors.transform(v.x(), v.y(), scaleX, scaleY, rotation, tx, ty, into);
+    }
+
     @Override // from Transform
     public Vector transform (IVector v, Vector into) {
         return Vectors.transform(v.x(), v.y(), scaleX, scaleY, rotation, into);

src/main/java/pythagoras/f/Plane.java

@@ -129,7 +129,7 @@ public class Plane implements IPlane, Serializable
     //  *
     //  * @return a reference to this plane, for chaining.
     //  */
-    // public Plane transformLocal (Transform transform) {
+    // public Plane transformLocal (Transform3D transform) {
     //     return transform(transform, this);
     // }
 
@@ -163,12 +163,12 @@ public class Plane implements IPlane, Serializable
     }
 
     // @Override // from IPlane
-    // public Plane transform (Transform transform) {
+    // public Plane transform (Transform3D transform) {
     //     return transform(transform, new Plane());
     // }
 
     // @Override // from IPlane
-    // public Plane transform (Transform transform, Plane result) {
+    // public Plane transform (Transform3D transform, Plane result) {
     //     transform.transformPointLocal(_normal.mult(-constant, _v1));
     //     transform.transformVector(_normal, _v2).normalizeLocal();
     //     return result.fromPointNormal(_v1, _v2);

src/main/java/pythagoras/f/Ray2.java

@@ -56,14 +56,14 @@ public class Ray2 implements IRay2
         return this;
     }
 
-    // /**
-    //  * Transforms this ray in-place.
-    //  *
-    //  * @return a reference to this ray, for chaining.
-    //  */
-    // public Ray2 transformLocal (Transform2D transform) {
-    //     return transform(transform, this);
-    // }
+    /**
+     * Transforms this ray in-place.
+     *
+     * @return a reference to this ray, for chaining.
+     */
+    public Ray2 transformLocal (Transform transform) {
+        return transform(transform, this);
+    }
 
     @Override // from IRay2
     public IVector origin () {
@@ -75,17 +75,17 @@ public class Ray2 implements IRay2
         return direction;
     }
 
-    // @Override // from IRay2
-    // public Ray2 transform (Transform2D transform) {
-    //     return transform(transform, new Ray2());
-    // }
+    @Override // from IRay2
+    public Ray2 transform (Transform transform) {
+        return transform(transform, new Ray2());
+    }
 
-    // @Override // from IRay2
-    // public Ray2 transform (Transform2D transform, Ray2 result) {
-    //     transform.transformPoint(origin, result.origin);
-    //     transform.transformVector(direction, result.direction).normalizeLocal();
-    //     return result;
-    // }
+    @Override // from IRay2
+    public Ray2 transform (Transform transform, Ray2 result) {
+        transform.transformPoint(origin, result.origin);
+        transform.transform(direction, result.direction).normalizeLocal();
+        return result;
+    }
 
     @Override // from IRay2
     public boolean intersects (IVector pt) {

src/main/java/pythagoras/f/RigidTransform.java

@@ -145,7 +145,7 @@ public class RigidTransform extends AbstractTransform
     }
 
     @Override // from Transform
-    public void transform (IPoint[] src, int srcOff, Point[] dst, int dstOff, int count) { 
+    public void transform (IPoint[] src, int srcOff, Point[] dst, int dstOff, int count) {
         float sina = FloatMath.sin(rotation), cosa = FloatMath.cos(rotation);
         for (int ii = 0; ii < count; ii++) {
             IPoint s = src[srcOff++];
@@ -169,6 +169,11 @@ public class RigidTransform extends AbstractTransform
         return Points.inverseTransform(p.x(), p.y(), 1, 1, rotation, tx, ty, into);
     }
 
+    @Override // from Transform
+    public Vector transformPoint (IVector v, Vector into) {
+        return Vectors.transform(v.x(), v.y(), 1, 1, rotation, tx, ty, into);
+    }
+
     @Override // from Transform
     public Vector transform (IVector v, Vector into) {
         return v.rotate(rotation, into);

src/main/java/pythagoras/f/Transform.java

@@ -176,6 +176,12 @@ public interface Transform
      * @throws NoninvertibleTransformException if the transform is not invertible. */
     Point inverseTransform (IPoint p, Point into);
 
+    /** Transforms the supplied vector as a point (accounting for translation), writing the result
+     * into {@code into}.
+     * @param into a vector into which to store the result, may be the same object as {@code v}.
+     * @return {@code into}, for chaining. */
+    Vector transformPoint (IVector v, Vector into);
+
     /** Transforms the supplied vector, writing the result into {@code into}.
      * @param into a vector into which to store the result, may be the same object as {@code v}.
      * @return {@code into}, for chaining. */

src/main/java/pythagoras/f/UniformTransform.java

@@ -197,6 +197,11 @@ public class UniformTransform extends AbstractTransform
         return Points.inverseTransform(p.x(), p.y(), scale, scale, rotation, tx, ty, into);
     }
 
+    @Override // from Transform
+    public Vector transformPoint (IVector p, Vector into) {
+        return Vectors.transform(p.x(), p.y(), scale, scale, rotation, tx, ty, into);
+    }
+
     @Override // from Transform
     public Vector transform (IVector v, Vector into) {
         return Vectors.transform(v.x(), v.y(), scale, scale, rotation, into);

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

@@ -85,12 +85,21 @@ public class Vectors
         return Math.abs(v1.x() - v2.x()) <= epsilon && Math.abs(v1.y() - v2.y()) <= epsilon;
     }
 
+    /** Transforms a vector as specified (as a point, accounting for translation), storing the
+     * result in the vector provided.
+     * @return a reference to the result vector, for chaining. */
+    public static Vector transform (float x, float y, float sx, float sy, float rotation,
+                                    float tx, float ty, Vector result) {
+        return transform(x, y, sx, sy, FloatMath.sin(rotation), FloatMath.cos(rotation), tx, ty,
+                         result);
+    }
+
     /**
-     * Transforms a point as specified, storing the result in the point provided.
+     * Transforms a vector as specified, storing the result in the vector provided.
      * @return a reference to the result vector, for chaining.
      */
     public static Vector transform (float x, float y, float sx, float sy, float rotation,
-                                   Vector result) {
+                                    Vector result) {
         return transform(x, y, sx, sy, FloatMath.sin(rotation), FloatMath.cos(rotation), result);
     }
 
@@ -103,8 +112,16 @@ public class Vectors
         return result.set((x*cosa - y*sina) * sx, (x*sina + y*cosa) * sy);
     }
 
+    /** Transforms a vector as specified (as a point, accounting for translation), storing the
+     * result in the vector provided.
+     * @return a reference to the result vector, for chaining. */
+    public static Vector transform (float x, float y, float sx, float sy, float sina, float cosa,
+                                    float tx, float ty, Vector result) {
+        return result.set((x*cosa - y*sina) * sx + tx, (x*sina + y*cosa) * sy + ty);
+    }
+
     /**
-     * Inverse transforms a point as specified, storing the result in the point provided.
+     * Inverse transforms a vector as specified, storing the result in the vector provided.
      * @return a reference to the result vector, for chaining.
      */
     public static Vector inverseTransform (float x, float y, float sx, float sy, float rotation,