SineTiming.java revision 8a6199f0c36a778f22394364347a301b0b28e94b 
1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2013 Eric Lafortune (eric@graphics.cornell.edu)
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21package proguard.gui.splash;
22
23/**
24 * This Timing varies between 0 and 1, as a sine wave over time.
25 *
26 * @author Eric Lafortune
27 */
28public class SineTiming implements Timing
29{
30    private final long period;
31    private final long phase;
32
33
34    /**
35     * Creates a new SineTiming.
36     * @param period the time period for a full cycle.
37     * @param phase  the phase of the cycle, which is added to the actual time.
38     */
39    public SineTiming(long period, long phase)
40    {
41        this.period = period;
42        this.phase  = phase;
43    }
44
45
46    // Implementation for Timing.
47
48    public double getTiming(long time)
49    {
50        // Compute the translated and scaled sine function.
51        return 0.5 + 0.5 * Math.sin(2.0 * Math.PI * (time + phase) / period);
52    }
53}
54