1 /*
2 * Copyright (c) 2007, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package com.sun.media.sound;
26
27 /**
28 * LFO control signal generator.
29 *
30 * @author Karl Helgason
31 */
32 public final class SoftLowFrequencyOscillator implements SoftProcess {
33
34 private final int max_count = 10;
35 private int used_count = 0;
36 private final double[][] out = new double[max_count][1];
37 private final double[][] delay = new double[max_count][1];
38 private final double[][] delay2 = new double[max_count][1];
39 private final double[][] freq = new double[max_count][1];
40 private final int[] delay_counter = new int[max_count];
41 private final double[] sin_phase = new double[max_count];
42 private final double[] sin_stepfreq = new double[max_count];
43 private final double[] sin_step = new double[max_count];
44 private double control_time = 0;
45 private double sin_factor = 0;
46 private static final double PI2 = 2.0 * Math.PI;
47
48 public SoftLowFrequencyOscillator() {
49 // If sin_step is 0 then sin_stepfreq must be -INF
50 for (int i = 0; i < sin_stepfreq.length; i++) {
51 sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
52 }
53 }
54
55 public void reset() {
56 for (int i = 0; i < used_count; i++) {
57 out[i][0] = 0;
58 delay[i][0] = 0;
59 delay2[i][0] = 0;
60 freq[i][0] = 0;
61 delay_counter[i] = 0;
62 sin_phase[i] = 0;
63 // If sin_step is 0 then sin_stepfreq must be -INF
64 sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
65 sin_step[i] = 0;
66 }
67 used_count = 0;
68 }
69
70 public void init(SoftSynthesizer synth) {
71 control_time = 1.0 / synth.getControlRate();
72 sin_factor = control_time * 2 * Math.PI;
73 for (int i = 0; i < used_count; i++) {
74 delay_counter[i] = (int)(Math.pow(2,
75 this.delay[i][0] / 1200.0) / control_time);
76 delay_counter[i] += (int)(delay2[i][0] / (control_time * 1000));
77 }
78 processControlLogic();
79 }
80
81 public void processControlLogic() {
82 for (int i = 0; i < used_count; i++) {
83 if (delay_counter[i] > 0) {
84 delay_counter[i]--;
85 out[i][0] = 0.5;
86 } else {
87 double f = freq[i][0];
88
89 if (sin_stepfreq[i] != f) {
90 sin_stepfreq[i] = f;
91 double fr = 440.0 * Math.exp(
92 (f - 6900.0) * (Math.log(2) / 1200.0));
93 sin_step[i] = fr * sin_factor;
94 }
95 /*
96 double fr = 440.0 * Math.pow(2.0,
97 (freq[i][0] - 6900.0) / 1200.0);
98 sin_phase[i] += fr * sin_factor;
99 */
100 /*
101 sin_phase[i] += sin_step[i];
102 while (sin_phase[i] > PI2)
103 sin_phase[i] -= PI2;
104 out[i][0] = 0.5 + Math.sin(sin_phase[i]) * 0.5;
105 */
106 double p = sin_phase[i];
107 p += sin_step[i];
108 while (p > PI2)
109 p -= PI2;
110 out[i][0] = 0.5 + Math.sin(p) * 0.5;
111 sin_phase[i] = p;
112
113 }
114 }
115 }
116
117 public double[] get(int instance, String name) {
118 if (instance >= used_count)
119 used_count = instance + 1;
120 if (name == null)
121 return out[instance];
122 if (name.equals("delay"))
123 return delay[instance];
124 if (name.equals("delay2"))
125 return delay2[instance];
126 if (name.equals("freq"))
127 return freq[instance];
128 return null;
129 }
130 }