1/*
2 * ProGuard -- shrinking, optimization, obfuscation, and preverification
3 *             of Java bytecode.
4 *
5 * Copyright (c) 2002-2009 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 ramps up smoothly from 0 to 1 in a given time interval.
25 *
26 * @author Eric Lafortune
27 */
28public class SmoothTiming implements Timing
29{
30    private final long fromTime;
31    private final long toTime;
32
33
34    /**
35     * Creates a new SmoothTiming.
36     * @param fromTime the time at which the timing starts ramping up from 0.
37     * @param toTime   the time at which the timing stops ramping up at 1.
38     */
39    public SmoothTiming(long fromTime, long toTime)
40    {
41        this.fromTime = fromTime;
42        this.toTime   = toTime;
43    }
44
45
46    // Implementation for Timing.
47
48    public double getTiming(long time)
49    {
50        if (time <= fromTime)
51        {
52            return 0.0;
53        }
54
55        if (time >= toTime)
56        {
57            return 1.0;
58        }
59
60        // Compute the linear interpolation.
61        double timing = (double) (time - fromTime) / (double) (toTime - fromTime);
62
63        // Smooth the interpolation at the ends.
64        return timing * timing * (3.0 - 2.0 * timing);
65    }
66}
67