1 package org.lcsim.spacegeom;
2 /** Abstract interface for a class that transforms a SpacePoint
3 * or SpacePointVector.
4 *
5 * Transformation may be invoked with xf.apply(spt) or xf(spt).
6 * Inverse may be applied with xf.inverse()(spt) or xf.invert(spt).
7 * In all cases the original value is unchanged and the transformed
8 * value is returned.
9 *
10 *@author Norman A. Graf
11 *@version $Id: SpaceXform.java,v 1.1.1.1 2010/12/01 00:15:57 jeremy Exp $
12 */
13
14 public abstract class SpaceXform
15 {
16
17 // methods to be implemented in subclass
18
19 /** Return the inverse of this transformation.
20 * The subclass manages its inverse--the inverse transformation
21 * should be destroyed when and only when the original is destroyed.
22 * @return the inverse of this transformation
23 */
24 public abstract SpaceXform inverse();
25
26 /** Transform a space point.
27 * @param spt SpacePoint on which to apply this transform
28 * @return SpacePoint on which this transform has been applied
29 */
30 public abstract SpacePoint apply( SpacePoint spt );
31
32 /** Transform a space point vector.
33 * @param svec SpacePointVector on which to apply this transform
34 * @return SpacePointVector on which this transform has been applied
35 */
36 public abstract SpacePointVector apply( SpacePointVector svec );
37
38 // methods implemented here
39
40 /** Transform a space point.
41 * @param spt SpacePoint to transform
42 * @return transformed SpacePoint
43 */
44 public SpacePoint transform( SpacePoint spt )
45 {
46 return apply(spt);
47 }
48
49 /** Transform a space point vector.
50 * @param svec SpacePointVector to transform
51 * @return ransformed SpacePointVector
52 */
53 public SpacePointVector transform( SpacePointVector svec )
54 {
55 return apply(svec);
56 }
57
58 /** Transform a space point with inverse transformation.
59 */
60 SpacePoint invert( SpacePoint spt )
61 {
62 return inverse().apply(spt);
63 }
64
65 /** Transform a space point vector with inverse transformation.
66 */
67 SpacePoint invert( SpacePointVector svec)
68 {
69 return inverse().apply(svec).getStartPoint();
70 }
71
72 }