content: /*
   * Copyright (C) 2015 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.example.android.common.midi.synth;
  
  public class SawOscillator extends SynthUnit {
      private float mPhase = 0.0f;
      private float mPhaseIncrement = 0.01f;
      private float mFrequency = 0.0f;
      private float mFrequencyScaler = 1.0f;
      private float mAmplitude = 1.0f;
  
      public void setPitch(float pitch) {
          float freq = (float) pitchToFrequency(pitch);
          setFrequency(freq);
      }
  
      public void setFrequency(float frequency) {
          mFrequency = frequency;
          updatePhaseIncrement();
      }
  
      private void updatePhaseIncrement() {
          mPhaseIncrement = 2.0f * mFrequency * mFrequencyScaler / 48000.0f;
      }
  
      public void setAmplitude(float amplitude) {
          mAmplitude = amplitude;
      }
  
      public float getAmplitude() {
          return mAmplitude;
      }
  
      public float getFrequencyScaler() {
          return mFrequencyScaler;
      }
  
      public void setFrequencyScaler(float frequencyScaler) {
          mFrequencyScaler = frequencyScaler;
          updatePhaseIncrement();
      }
  
      float incrementWrapPhase() {
          mPhase += mPhaseIncrement;
          while (mPhase > 1.0) {
              mPhase -= 2.0;
          }
          while (mPhase < -1.0) {
              mPhase += 2.0;
          }
          return mPhase;
      }
  
      @Override
      public float render() {
          return incrementWrapPhase() * mAmplitude;
      }
  
  }
  