/*
   Copyright 2013 Google Inc.

   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.
*/

// Low frequency oscillator, compatible with DX7

class Lfo {
  public:
    static void init(FRAC_NUM sample_rate);
    void reset(const uint8_t params[6]);

    // result is 0..1 in Q24
    int32_t getsample();

    // result is 0..1 in Q24
    int32_t getdelay();

    void keydown();
  private:
    static uint32_t unit_;

    uint32_t phase_;  // Q32
    uint32_t delta_;
    uint8_t waveform_;
    uint8_t randstate_;
    bool sync_;

    uint32_t delaystate_;
    uint32_t delayinc_;
    uint32_t delayinc2_;
};