1 package org.lcsim.geometry;
2
3 import hep.physics.vec.BasicHep3Vector;
4 import hep.physics.vec.Hep3Vector;
5
6 /**
7 * A field map, allows getting the field at a given point
8 *
9 * @author tonyj
10 */
11 public interface FieldMap
12 {
13 /**
14 * Get the field magnitude and direction at a particular point.
15 *
16 * @param position The position at which the field is requested
17 * @param b The field (the object is passed by reference and set to the correct field)
18 */
19 public void getField( double[] position, double[] b );
20
21 /**
22 * Get the field magnitude and direction at a particular point. This method requires
23 * allocation of a new object on each call, and should therefore not be used if it may
24 * be called many times.
25 *
26 * @param position The position at which the field is requested
27 * @return The field.
28 * @deprecated @use getField(double[], double[])
29 */
30 public double[] getField( double[] position );
31
32 /**
33 * Get the field magnitude and direction at a particular point.
34 *
35 * @param position The position at which the field is requested.
36 * @param field The field. If not <code>null</code> this is passed by reference and
37 * set to the correct field
38 * @return The field. This will be the same object passed as field, unless field was
39 * <code>null</code>
40 */
41 public Hep3Vector getField( Hep3Vector position, BasicHep3Vector field );
42
43 /**
44 * Get the field magnitude and direction at a particular point. Equivalent to
45 * <code>getField(position,null)</code>.
46 */
47 public Hep3Vector getField( Hep3Vector position );
48 }