1 /*
2 * Copyright 2007-2008 motej
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package motejx.adapters;
17
18 import motej.IrPoint;
19 import motej.event.IrCameraEvent;
20 import motej.event.IrCameraListener;
21
22 /**
23 * StatefullIrCameraAdapter implements IrCameraListener to give additional
24 * information about infrared points in the WiiMotes camera sight.
25 *
26 * @author djuxen
27 */
28 public abstract class StatefulIrCameraAdapter implements IrCameraListener {
29
30 private IrCameraEvent lastEvent;
31
32 public void irImageChanged(IrCameraEvent evt) {
33 if (lastEvent != null) {
34 for (int i = 0; i < 4; i++) {
35 if (!evt.getIrPoint(i).equals(lastEvent.getIrPoint(i))) {
36 IrPoint currentPoint = evt.getIrPoint(i);
37 IrPoint lastPoint = lastEvent.getIrPoint(i);
38
39 if (isValid(currentPoint) && !isValid(lastPoint)) {
40 pointAppeared(i, currentPoint);
41 } else if (!isValid(currentPoint) && isValid(lastPoint)) {
42 pointDisappeared(i, lastPoint);
43 } else {
44 pointChanged(i, currentPoint);
45 }
46 }
47 }
48 }
49
50 lastEvent = evt;
51 }
52
53 /**
54 * Implement this method to get notified when an infrared point
55 * appears in the camera's view.
56 * @param slot The slot on which the point appeared
57 * @param p The point which appeared
58 */
59 public abstract void pointAppeared(int slot, IrPoint p);
60
61 /**
62 * Implement this method to get notified when an infrared point
63 * moves in the camera's view.
64 * @param slot The slot on which the point moved
65 * @param p The point which changed
66 */
67 public abstract void pointChanged(int slot, IrPoint p);
68
69 /**
70 * Implement this method to get notified when an infrared point
71 * disappears from the camera's view.
72 * @param slot The slot on which the point disappeared
73 * @param p The point which disappeared
74 */
75 public abstract void pointDisappeared(int slot, IrPoint p);
76
77 private boolean isValid(IrPoint irPoint) {
78 return irPoint.x != 1023 || irPoint.y != 1023;
79 }
80 }