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
26 package com.sun.media.sound;
27
28 /**
29 * LFO control signal generator.
30 *
31 * @author Karl Helgason
32 */
33 public final class SoftLowFrequencyOscillator implements SoftProcess {
34
35 private final int max_count = 10;
36 private int used_count = 0;
37 private final double[][] out = new double[max_count][1];
38 private final double[][] delay = new double[max_count][1];
39 private final double[][] delay2 = new double[max_count][1];
40 private final double[][] freq = new double[max_count][1];
41 private final int[] delay_counter = new int[max_count];
42 private final double[] sin_phase = new double[max_count];
43 private final double[] sin_stepfreq = new double[max_count];
44 private final double[] sin_step = new double[max_count];
45 private double control_time = 0;
46 private double sin_factor = 0;
47 private static final double PI2 = 2.0 * Math.PI;
48
49 public SoftLowFrequencyOscillator() {
50 // If sin_step is 0 then sin_stepfreq must be -INF
51 for (int i = 0; i < sin_stepfreq.length; i++) {
52 sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
53 }
54 }
55
56 @Override
57 public void reset() {
58 for (int i = 0; i < used_count; i++) {
59 out[i][0] = 0;
60 delay[i][0] = 0;
61 delay2[i][0] = 0;
62 freq[i][0] = 0;
63 delay_counter[i] = 0;
64 sin_phase[i] = 0;
65 // If sin_step is 0 then sin_stepfreq must be -INF
66 sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
67 sin_step[i] = 0;
68 }
69 used_count = 0;
70 }
71
72 @Override
73 public void init(SoftSynthesizer synth) {
74 control_time = 1.0 / synth.getControlRate();
75 sin_factor = control_time * 2 * Math.PI;
76 for (int i = 0; i < used_count; i++) {
77 delay_counter[i] = (int)(Math.pow(2,
78 this.delay[i][0] / 1200.0) / control_time);
79 delay_counter[i] += (int)(delay2[i][0] / (control_time * 1000));
80 }
81 processControlLogic();
82 }
83
84 @Override
85 public void processControlLogic() {
86 for (int i = 0; i < used_count; i++) {
87 if (delay_counter[i] > 0) {
88 delay_counter[i]--;
89 out[i][0] = 0.5;
90 } else {
91 double f = freq[i][0];
92
93 if (sin_stepfreq[i] != f) {
94 sin_stepfreq[i] = f;
95 double fr = 440.0 * Math.exp(
96 (f - 6900.0) * (Math.log(2) / 1200.0));
97 sin_step[i] = fr * sin_factor;
98 }
99 /*
100 double fr = 440.0 * Math.pow(2.0,
101 (freq[i][0] - 6900.0) / 1200.0);
102 sin_phase[i] += fr * sin_factor;
103 */
104 /*
105 sin_phase[i] += sin_step[i];
106 while (sin_phase[i] > PI2)
107 sin_phase[i] -= PI2;
108 out[i][0] = 0.5 + Math.sin(sin_phase[i]) * 0.5;
109 */
110 double p = sin_phase[i];
111 p += sin_step[i];
112 while (p > PI2)
113 p -= PI2;
114 out[i][0] = 0.5 + Math.sin(p) * 0.5;
115 sin_phase[i] = p;
116
117 }
118 }
119 }
120
121 @Override
122 public double[] get(int instance, String name) {
123 if (instance >= used_count)
124 used_count = instance + 1;
125 if (name == null)
126 return out[instance];
127 if (name.equals("delay"))
128 return delay[instance];
129 if (name.equals("delay2"))
130 return delay2[instance];
131 if (name.equals("freq"))
132 return freq[instance];
133 return null;
134 }
135 }