text: /*
   * Copyright (c) 2007, 2014, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package com.sun.media.sound;
  
  /**
   * AHDSR control signal envelope generator.
   *
   * @author Karl Helgason
   */
  public final class SoftEnvelopeGenerator implements SoftProcess {
  
      public static final int EG_OFF = 0;
      public static final int EG_DELAY = 1;
      public static final int EG_ATTACK = 2;
      public static final int EG_HOLD = 3;
      public static final int EG_DECAY = 4;
      public static final int EG_SUSTAIN = 5;
      public static final int EG_RELEASE = 6;
      public static final int EG_SHUTDOWN = 7;
      public static final int EG_END = 8;
      int max_count = 10;
      int used_count = 0;
      private final int[] stage = new int[max_count];
      private final int[] stage_ix = new int[max_count];
      private final double[] stage_v = new double[max_count];
      private final int[] stage_count = new int[max_count];
      private final double[][] on = new double[max_count][1];
      private final double[][] active = new double[max_count][1];
      private final double[][] out = new double[max_count][1];
      private final double[][] delay = new double[max_count][1];
      private final double[][] attack = new double[max_count][1];
      private final double[][] hold = new double[max_count][1];
      private final double[][] decay = new double[max_count][1];
      private final double[][] sustain = new double[max_count][1];
      private final double[][] release = new double[max_count][1];
      private final double[][] shutdown = new double[max_count][1];
      private final double[][] release2 = new double[max_count][1];
      private final double[][] attack2 = new double[max_count][1];
      private final double[][] decay2 = new double[max_count][1];
      private double control_time = 0;
  
      @Override
      public void reset() {
          for (int i = 0; i < used_count; i++) {
              stage[i] = 0;
              on[i][0] = 0;
              out[i][0] = 0;
              delay[i][0] = 0;
              attack[i][0] = 0;
              hold[i][0] = 0;
              decay[i][0] = 0;
              sustain[i][0] = 0;
              release[i][0] = 0;
              shutdown[i][0] = 0;
              attack2[i][0] = 0;
              decay2[i][0] = 0;
              release2[i][0] = 0;
          }
          used_count = 0;
      }
  
      @Override
      public void init(SoftSynthesizer synth) {
          control_time = 1.0 / synth.getControlRate();
          processControlLogic();
      }
  
      @Override
      public double[] get(int instance, String name) {
          if (instance >= used_count)
              used_count = instance + 1;
          if (name == null)
              return out[instance];
          if (name.equals("on"))
              return on[instance];
          if (name.equals("active"))
              return active[instance];
          if (name.equals("delay"))
              return delay[instance];
          if (name.equals("attack"))
              return attack[instance];
          if (name.equals("hold"))
              return hold[instance];
          if (name.equals("decay"))
              return decay[instance];
          if (name.equals("sustain"))
              return sustain[instance];
          if (name.equals("release"))
              return release[instance];
          if (name.equals("shutdown"))
              return shutdown[instance];
          if (name.equals("attack2"))
              return attack2[instance];
          if (name.equals("decay2"))
              return decay2[instance];
          if (name.equals("release2"))
              return release2[instance];
  
          return null;
      }
  
      @Override
      @SuppressWarnings("fallthrough")
      public void processControlLogic() {
          for (int i = 0; i < used_count; i++) {
  
              if (stage[i] == EG_END)
                  continue;
  
              if ((stage[i] > EG_OFF) && (stage[i] < EG_RELEASE)) {
                  if (on[i][0] < 0.5) {
                      if (on[i][0] < -0.5) {
                          stage_count[i] = (int)(Math.pow(2,
                                  this.shutdown[i][0] / 1200.0) / control_time);
                          if (stage_count[i] < 0)
                              stage_count[i] = 0;
                          stage_v[i] = out[i][0];
                          stage_ix[i] = 0;
                          stage[i] = EG_SHUTDOWN;
                      } else {
                          if ((release2[i][0] < 0.000001) && release[i][0] < 0
                                  && Double.isInfinite(release[i][0])) {
                              out[i][0] = 0;
                              active[i][0] = 0;
                              stage[i] = EG_END;
                              continue;
                          }
  
                          stage_count[i] = (int)(Math.pow(2,
                                  this.release[i][0] / 1200.0) / control_time);
                          stage_count[i]
                                  += (int)(this.release2[i][0]/(control_time * 1000));
                          if (stage_count[i] < 0)
                              stage_count[i] = 0;
                          // stage_v[i] = out[i][0];
                          stage_ix[i] = 0;
  
                          double m = 1 - out[i][0];
                          stage_ix[i] = (int)(stage_count[i] * m);
  
                          stage[i] = EG_RELEASE;
                      }
                  }
              }
  
              switch (stage[i]) {
              case EG_OFF:
                  active[i][0] = 1;
                  if (on[i][0] < 0.5)
                      break;
                  stage[i] = EG_DELAY;
                  stage_ix[i] = (int)(Math.pow(2,
                          this.delay[i][0] / 1200.0) / control_time);
                  if (stage_ix[i] < 0)
                      stage_ix[i] = 0;
                  // Fallthrough
              case EG_DELAY:
                  if (stage_ix[i] == 0) {
                      double attack = this.attack[i][0];
                      double attack2 = this.attack2[i][0];
  
                      if (attack2 < 0.000001
                              && (attack < 0 && Double.isInfinite(attack))) {
                          out[i][0] = 1;
                          stage[i] = EG_HOLD;
                          stage_count[i] = (int)(Math.pow(2,
                                  this.hold[i][0] / 1200.0) / control_time);
                          stage_ix[i] = 0;
                      } else {
                          stage[i] = EG_ATTACK;
                          stage_count[i] = (int)(Math.pow(2,
                                  attack / 1200.0) / control_time);
                          stage_count[i] += (int)(attack2 / (control_time * 1000));
                          if (stage_count[i] < 0)
                              stage_count[i] = 0;
                          stage_ix[i] = 0;
                      }
                  } else
                      stage_ix[i]--;
                  break;
              case EG_ATTACK:
                  stage_ix[i]++;
                  if (stage_ix[i] >= stage_count[i]) {
                      out[i][0] = 1;
                      stage[i] = EG_HOLD;
                  } else {
                      // CONVEX attack
                      double a = ((double)stage_ix[i]) / ((double)stage_count[i]);
                      a = 1 + ((40.0 / 96.0) / Math.log(10)) * Math.log(a);
                      if (a < 0)
                          a = 0;
                      else if (a > 1)
                          a = 1;
                      out[i][0] = a;
                  }
                  break;
              case EG_HOLD:
                  stage_ix[i]++;
                  if (stage_ix[i] >= stage_count[i]) {
                      stage[i] = EG_DECAY;
                      stage_count[i] = (int)(Math.pow(2,
                              this.decay[i][0] / 1200.0) / control_time);
                      stage_count[i] += (int)(this.decay2[i][0]/(control_time*1000));
                      if (stage_count[i] < 0)
                          stage_count[i] = 0;
                      stage_ix[i] = 0;
                  }
                  break;
              case EG_DECAY:
                  stage_ix[i]++;
                  double sustain = this.sustain[i][0] * (1.0 / 1000.0);
                  if (stage_ix[i] >= stage_count[i]) {
                      out[i][0] = sustain;
                      stage[i] = EG_SUSTAIN;
                      if (sustain < 0.001) {
                          out[i][0] = 0;
                          active[i][0] = 0;
                          stage[i] = EG_END;
                      }
                  } else {
                      double m = ((double)stage_ix[i]) / ((double)stage_count[i]);
                      out[i][0] = (1 - m) + sustain * m;
                  }
                  break;
              case EG_SUSTAIN:
                  break;
              case EG_RELEASE:
                  stage_ix[i]++;
                  if (stage_ix[i] >= stage_count[i]) {
                      out[i][0] = 0;
                      active[i][0] = 0;
                      stage[i] = EG_END;
                  } else {
                      double m = ((double)stage_ix[i]) / ((double)stage_count[i]);
                      out[i][0] = (1 - m); // *stage_v[i];
  
                      if (on[i][0] < -0.5) {
                          stage_count[i] = (int)(Math.pow(2,
                                  this.shutdown[i][0] / 1200.0) / control_time);
                          if (stage_count[i] < 0)
                              stage_count[i] = 0;
                          stage_v[i] = out[i][0];
                          stage_ix[i] = 0;
                          stage[i] = EG_SHUTDOWN;
                      }
  
                      // re-damping
                      if (on[i][0] > 0.5) {
                          sustain = this.sustain[i][0] * (1.0 / 1000.0);
                          if (out[i][0] > sustain) {
                              stage[i] = EG_DECAY;
                              stage_count[i] = (int)(Math.pow(2,
                                      this.decay[i][0] / 1200.0) / control_time);
                              stage_count[i] +=
                                      (int)(this.decay2[i][0]/(control_time*1000));
                              if (stage_count[i] < 0)
                                  stage_count[i] = 0;
                              m = (out[i][0] - 1) / (sustain - 1);
                              stage_ix[i] = (int) (stage_count[i] * m);
                          }
                      }
  
                  }
                  break;
              case EG_SHUTDOWN:
                  stage_ix[i]++;
                  if (stage_ix[i] >= stage_count[i]) {
                      out[i][0] = 0;
                      active[i][0] = 0;
                      stage[i] = EG_END;
                  } else {
                      double m = ((double)stage_ix[i]) / ((double)stage_count[i]);
                      out[i][0] = (1 - m) * stage_v[i];
                  }
                  break;
              default:
                  break;
              }
          }
      }
  }
  