furnace/src/engine/sample.h

/**
 * Furnace Tracker - multi-system chiptune tracker
 * Copyright (C) 2021-2022 tildearrow and contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "../ta-utils.h"

enum DivResampleFilters {
  DIV_RESAMPLE_NONE=0,
  DIV_RESAMPLE_LINEAR,
  DIV_RESAMPLE_CUBIC,
  DIV_RESAMPLE_BLEP,
  DIV_RESAMPLE_SINC,
  DIV_RESAMPLE_BEST
};

struct DivSample {
  String name;
  int rate, centerRate, loopStart, loopOffP;
  // valid values are:
  // - 0: ZX Spectrum overlay drum (1-bit)
  // - 1: 1-bit NES DPCM (1-bit)
  // - 4: QSound ADPCM
  // - 5: ADPCM-A
  // - 6: ADPCM-B
  // - 7: X68000 ADPCM
  // - 8: 8-bit PCM
  // - 9: BRR (SNES)
  // - 10: VOX
  // - 16: 16-bit PCM
  unsigned char depth;

  // these are the new data structures.
  signed char* data8; // 8
  short* data16; // 16
  unsigned char* data1; // 0
  unsigned char* dataDPCM; // 1
  unsigned char* dataQSoundA; // 4
  unsigned char* dataA; // 5
  unsigned char* dataB; // 6
  unsigned char* dataX68; // 7
  unsigned char* dataBRR; // 9
  unsigned char* dataVOX; // 10

  unsigned int length8, length16, length1, lengthDPCM, lengthQSoundA, lengthA, lengthB, lengthX68, lengthBRR, lengthVOX;
  unsigned int off8, off16, off1, offDPCM, offQSoundA, offA, offB, offX68, offBRR, offVOX;
  unsigned int offSegaPCM, offQSound, offX1_010;

  unsigned int samples;

  /**
   * @warning DO NOT USE - internal functions
   */
  bool resampleNone(double rate);
  bool resampleLinear(double rate);
  bool resampleCubic(double rate);
  bool resampleBlep(double rate);
  bool resampleSinc(double rate);

  /**
   * save this sample to a file.
   * @param path a path.
   * @return whether saving succeeded or not.
   */
  bool save(const char* path);

  /**
   * @warning DO NOT USE - internal function
   * initialize sample data.
   * @param d sample type.
   * @param count number of samples.
   * @return whether it was successful.
   */
  bool initInternal(unsigned char d, int count);

  /**
   * initialize sample data. make sure you have set `depth` before doing so.
   * @param count number of samples.
   * @return whether it was successful.
   */
  bool init(unsigned int count);

  /**
   * resize sample data. make sure the sample has been initialized before doing so.
   * @warning do not attempt to resize a sample outside of a synchronized block!
   * @param count number of samples.
   * @return whether it was successful.
   */
  bool resize(unsigned int count);

  /**
   * change the sample rate.
   * @warning do not attempt to resample outside of a synchronized block!
   * @param rate number of samples.
   * @param filter the interpolation filter.
   * @return whether it was successful.
   */
  bool resample(double rate, int filter);

  /**
   * initialize the rest of sample formats for this sample.
   */
  void render();

  /**
   * get the sample data for the current depth.
   * @return the sample data, or NULL if not created.
   */
  void* getCurBuf();

  /**
   * get the sample data length for the current depth.
   * @return the sample data length.
   */
  unsigned int getCurBufLen();
  DivSample():
    name(""),
    rate(32000),
    centerRate(8363),
    loopStart(-1),
    loopOffP(0),
    depth(16),
    data8(NULL),
    data16(NULL),
    data1(NULL),
    dataDPCM(NULL),
    dataQSoundA(NULL),
    dataA(NULL),
    dataB(NULL),
    dataX68(NULL),
    dataBRR(NULL),
    dataVOX(NULL),
    length8(0),
    length16(0),
    length1(0),
    lengthDPCM(0),
    lengthQSoundA(0),
    lengthA(0),
    lengthB(0),
    lengthX68(0),
    lengthBRR(0),
    lengthVOX(0),
    off8(0),
    off16(0),
    off1(0),
    offDPCM(0),
    offQSoundA(0),
    offA(0),
    offB(0),
    offX68(0),
    offBRR(0),
    offVOX(0),
    offSegaPCM(0),
    offQSound(0),
    samples(0) {}
  ~DivSample();
};