/*  TinySoundFont - v0.8 - SoundFont2 synthesizer - https://github.com/schellingb/TinySoundFont
                                     no warranty implied; use at your own risk
    Do this:
      #define TSF_IMPLEMENTATION
    before you include this file in *one* C or C++ file to create the implementation.
    // i.e. it should look like this:
    #include ...
    #include ...
    #define TSF_IMPLEMENTATION
    #include "tsf.h"

    [OPTIONAL] #define TSF_NO_STDIO to remove stdio dependency
    [OPTIONAL] #define TSF_MALLOC, TSF_REALLOC, and TSF_FREE to avoid stdlib.h
    [OPTIONAL] #define TSF_MEMCPY, TSF_MEMSET to avoid string.h
    [OPTIONAL] #define TSF_POW, TSF_POWF, TSF_EXPF, TSF_LOG, TSF_TAN, TSF_LOG10, TSF_SQRT to avoid math.h

    NOT YET IMPLEMENTED
     - Support for ChorusEffectsSend and ReverbEffectsSend generators
     - Better low-pass filter without lowering performance too much
     - Support for modulators

    LICENSE (MIT)

    Copyright (C) 2017, 2018 Bernhard Schelling
    Based on SFZero, Copyright (C) 2012 Steve Folta (https://github.com/stevefolta/SFZero)

    Permission is hereby granted, free of charge, to any person obtaining a copy of this
    software and associated documentation files (the "Software"), to deal in the Software
    without restriction, including without limitation the rights to use, copy, modify, merge,
    publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
    to whom the Software is furnished to do so, subject to the following conditions:

    The above copyright notice and this permission notice shall be included in all
    copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
    INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
    PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
    USE OR OTHER DEALINGS IN THE SOFTWARE.

*/

// ESP32 as of 3.x has a compiler bug in this section, with the G++ generated assembly
// being illegal.  There's nothing wrong with the code here, it just looks like an
// Xtensa backend issue.  Until that's fixed, no MIDI for you!
///home/earle/Arduino/libraries/ESP8266Audio/src/libtinysoundfont/tsf.h: In function 'void tsf_channel_midi_control(tsf*, int, int, int)':
// /home/earle/Arduino/libraries/ESP8266Audio/src/libtinysoundfont/tsf.h:2101:1: error: insn does not satisfy its constraints:
//  2101 | }
//       | ^

#if defined(ESP32) && (__GNUC__ >= 8) && (__XTENSA__)
// Not defined, can't build
#else

#ifndef TSF_INCLUDE_TSF_INL
#define TSF_INCLUDE_TSF_INL

#ifdef __cplusplus
extern "C" {
#  define CPP_DEFAULT0 = 0
#else
#  define CPP_DEFAULT0
#endif

//define this if you want the API functions to be static
#ifdef TSF_STATIC
#define TSFDEF static
#else
#define TSFDEF extern
#endif

// The load functions will return a pointer to a struct tsf which all functions
// thereafter take as the first parameter.
// On error the tsf_load* functions will return NULL most likely due to invalid
// data (or if the file did not exist in tsf_load_filename).
typedef struct tsf tsf;

#ifndef TSF_NO_STDIO
// Directly load a SoundFont from a .sf2 file path
TSFDEF tsf* tsf_load_filename(const char* filename);
#endif

// Load a SoundFont from a block of memory
TSFDEF tsf* tsf_load_memory(const void* buffer, int size);

// Stream structure for the generic loading
struct tsf_stream {
    // Custom data given to the functions as the first parameter
    void* data;

    // Function pointer will be called to read 'size' bytes into ptr (returns number of read bytes)
    int (*read)(void* data, void* ptr, unsigned int size);

    // Function pointer will be called to skip ahead over 'count' bytes
    int (*tell)(void* data);

    // Function pointer will be called to skip ahead over 'count' bytes (returns 1 on success, 0 on error)
    int (*skip)(void* data, unsigned int count);

    // Function pointer will be called to seek to absolute position
    int (*seek)(void* data, unsigned int pos);

    // Function pointer will be called to skip ahead over 'count' bytes
    int (*close)(void* data);

    // Function pointer will be called to skip ahead over 'count' bytes
    int (*size)(void* data);
};

// Generic SoundFont loading method using the stream structure above
TSFDEF tsf* tsf_load(struct tsf_stream* stream);

// Free the memory related to this tsf instance
TSFDEF void tsf_close(tsf* f);

// Stop all playing notes immediately and reset all channel parameters
TSFDEF void tsf_reset(tsf* f);

// Returns the preset index from a bank and preset number, or -1 if it does not exist in the loaded SoundFont
TSFDEF int tsf_get_presetindex(const tsf* f, int bank, int preset_number);

// Returns the number of presets in the loaded SoundFont
TSFDEF int tsf_get_presetcount(const tsf* f);

// Returns the name of a preset index >= 0 and < tsf_get_presetcount()
TSFDEF const char* tsf_get_presetname(const tsf* f, int preset_index);

// Returns the name of a preset by bank and preset number
TSFDEF const char* tsf_bank_get_presetname(const tsf* f, int bank, int preset_number);

// Supported output modes by the render methods
enum TSFOutputMode {
    // Two channels with single left/right samples one after another
    TSF_STEREO_INTERLEAVED,
    // Two channels with all samples for the left channel first then right
    TSF_STEREO_UNWEAVED,
    // A single channel (stereo instruments are mixed into center)
    TSF_MONO
};

// Thread safety:
// Your audio output which calls the tsf_render* functions will most likely
// run on a different thread than where the playback tsf_note* functions
// are called. In which case some sort of concurrency control like a
// mutex needs to be used so they are not called at the same time.

// Setup the parameters for the voice render methods
//   outputmode: if mono or stereo and how stereo channel data is ordered
//   samplerate: the number of samples per second (output frequency)
//   global_gain_db: volume gain in decibels (>0 means higher, <0 means lower)
TSFDEF void tsf_set_output(tsf* f, enum TSFOutputMode outputmode, int samplerate, float global_gain_db CPP_DEFAULT0);

// Start playing a note
//   preset_index: preset index >= 0 and < tsf_get_presetcount()
//   key: note value between 0 and 127 (60 being middle C)
//   vel: velocity as a float between 0.0 (equal to note off) and 1.0 (full)
//   bank: instrument bank number (alternative to preset_index)
//   preset_number: preset number (alternative to preset_index)
//   (bank_note_on returns 0 if preset does not exist, otherwise 1)
TSFDEF void tsf_note_on(tsf* f, int preset_index, int key, float vel);
TSFDEF int  tsf_bank_note_on(tsf* f, int bank, int preset_number, int key, float vel);

// Stop playing a note
//   (bank_note_off returns 0 if preset does not exist, otherwise 1)
TSFDEF void tsf_note_off(tsf* f, int preset_index, int key);
TSFDEF int  tsf_bank_note_off(tsf* f, int bank, int preset_number, int key);

// Stop playing all notes (end with sustain and release)
TSFDEF void tsf_note_off_all(tsf* f);

// Returns the number of active voices
TSFDEF int tsf_active_voice_count(tsf* f);

// Render output samples into a buffer
// You can either render as signed 16-bit values (tsf_render_short) or
// as 32-bit float values (tsf_render_float)
//   buffer: target buffer of size samples * output_channels * sizeof(type)
//   samples: number of samples to render
//   flag_mixing: if 0 clear the buffer first, otherwise mix into existing data
TSFDEF void tsf_render_short(tsf* f, short* buffer, int samples, int flag_mixing CPP_DEFAULT0);
TSFDEF void tsf_render_float(tsf* f, float* buffer, int samples, int flag_mixing CPP_DEFAULT0);

// Higher level channel based functions, set up channel parameters
//   channel: channel number
//   preset_index: preset index >= 0 and < tsf_get_presetcount()
//   preset_number: preset number (alternative to preset_index)
//   flag_mididrums: 0 for normal channels, otherwise apply MIDI drum channel rules
//   bank: instrument bank number (alternative to preset_index)
//   pan: stereo panning value from 0.0 (left) to 1.0 (right) (default 0.5 center)
//   volume: linear volume scale factor (default 1.0 full)
//   pitch_wheel: pitch wheel position 0 to 16383 (default 8192 unpitched)
//   pitch_range: range of the pitch wheel in semitones (default 2.0, total +/- 2 semitones)
//   tuning: tuning of all playing voices in semitones (default 0.0, standard (A440) tuning)
//   (set_preset_number and set_bank_preset return 0 if preset does not exist, otherwise 1)
TSFDEF void tsf_channel_set_presetindex(tsf* f, int channel, int preset_index);
TSFDEF int  tsf_channel_set_presetnumber(tsf* f, int channel, int preset_number, int flag_mididrums CPP_DEFAULT0);
TSFDEF void tsf_channel_set_bank(tsf* f, int channel, int bank);
TSFDEF int  tsf_channel_set_bank_preset(tsf* f, int channel, int bank, int preset_number);
TSFDEF void tsf_channel_set_pan(tsf* f, int channel, float pan);
TSFDEF void tsf_channel_set_volume(tsf* f, int channel, float volume);
TSFDEF void tsf_channel_set_pitchwheel(tsf* f, int channel, int pitch_wheel);
TSFDEF void tsf_channel_set_pitchrange(tsf* f, int channel, float pitch_range);
TSFDEF void tsf_channel_set_tuning(tsf* f, int channel, float tuning);

// Start or stop playing notes on a channel (needs channel preset to be set)
//   channel: channel number
//   key: note value between 0 and 127 (60 being middle C)
//   vel: velocity as a float between 0.0 (equal to note off) and 1.0 (full)
TSFDEF void tsf_channel_note_on(tsf* f, int channel, int key, float vel);
TSFDEF void tsf_channel_note_off(tsf* f, int channel, int key);
TSFDEF void tsf_channel_note_off_all(tsf* f, int channel); //end with sustain and release
TSFDEF void tsf_channel_sounds_off_all(tsf* f, int channel); //end immediately

// Apply a MIDI control change to the channel (not all controllers are supported!)
TSFDEF void tsf_channel_midi_control(tsf* f, int channel, int controller, int control_value);

// Get current values set on the channels
TSFDEF int tsf_channel_get_preset_index(tsf* f, int channel);
TSFDEF int tsf_channel_get_preset_bank(tsf* f, int channel);
TSFDEF int tsf_channel_get_preset_number(tsf* f, int channel);
TSFDEF float tsf_channel_get_pan(tsf* f, int channel);
TSFDEF float tsf_channel_get_volume(tsf* f, int channel);
TSFDEF int tsf_channel_get_pitchwheel(tsf* f, int channel);
TSFDEF float tsf_channel_get_pitchrange(tsf* f, int channel);
TSFDEF float tsf_channel_get_tuning(tsf* f, int channel);

#ifdef __cplusplus
#  undef CPP_DEFAULT0
}
#endif

// end header
// ---------------------------------------------------------------------------------------------------------
#endif //TSF_INCLUDE_TSF_INL

#ifdef TSF_IMPLEMENTATION

// The lower this block size is the more accurate the effects are.
// Increasing the value significantly lowers the CPU usage of the voice rendering.
// If LFO affects the low-pass filter it can be hearable even as low as 8.
#ifndef TSF_RENDER_EFFECTSAMPLEBLOCK
#define TSF_RENDER_EFFECTSAMPLEBLOCK 64
#endif

// Grace release time for quick voice off (avoid clicking noise)
#define TSF_FASTRELEASETIME 0.01f
#if !defined(TSF_MALLOC) || !defined(TSF_FREE) || !defined(TSF_REALLOC)
#  include <stdlib.h>
#  define TSF_MALLOC  malloc
#  define TSF_FREE    free
#  define TSF_REALLOC realloc
#endif

#if !defined(TSF_MEMCPY) || !defined(TSF_MEMSET)
#  include <string.h>
#  define TSF_MEMCPY  memcpy
#  define TSF_MEMSET  memset
#endif

#if !defined(TSF_POW) || !defined(TSF_POWF) || !defined(TSF_EXPF) || !defined(TSF_LOG) || !defined(TSF_TAN) || !defined(TSF_LOG10) || !defined(TSF_SQRT)
#  include <math.h>
#  if !defined(__cplusplus) && !defined(NAN) && !defined(powf) && !defined(expf) && !defined(sqrtf)
#    define powf (float)pow // deal with old math.h
#    define expf (float)exp // files that come without
#    define sqrtf (float)sqrt // powf, expf and sqrtf
#  endif
#  define TSF_POW     pow
#  define TSF_POWF    powf
#  define TSF_EXPF    expf
#  define TSF_LOG     log
#  define TSF_TAN     tan
#  define TSF_LOG10   log10
#  define TSF_SQRTF   sqrtf
#endif

#ifndef TSF_NO_STDIO
#  include <stdio.h>
#endif

#define TSF_TRUE 1
#define TSF_FALSE 0
#define TSF_BOOL char
#define TSF_PI 3.14159265358979323846264338327950288
#define TSF_NULL 0

#ifdef __cplusplus
extern "C" {
#endif

typedef char tsf_fourcc[4];
typedef signed char tsf_s8;
typedef unsigned char tsf_u8;
typedef unsigned short tsf_u16;
typedef signed short tsf_s16;
typedef unsigned int tsf_u32;
typedef char tsf_char20[20];

#define TSF_FourCCEquals(value1, value2) (value1[0] == value2[0] && value1[1] == value2[1] && value1[2] == value2[2] && value1[3] == value2[3])

// Samples cache, number and sample count
#define TSF_BUFFS 16
#define TSF_BUFFSIZE 512

struct tsf {
    struct tsf_preset* presets;
    struct tsf_voice* voices;

    unsigned int fontSamplesOffset;
    unsigned int fontSampleCount;
    struct tsf_channels* channels;
    float* outputSamples;

    int presetNum;
    int voiceNum;
    int outputSampleSize;
    unsigned int voicePlayIndex;

    enum TSFOutputMode outputmode;
    float outSampleRate;
    float globalGainDB;

    struct tsf_hydra *hydra;

    // Cached sample read
    short *buffer[TSF_BUFFS];
    int offset[TSF_BUFFS];
    int timestamp[TSF_BUFFS];
    int epoch;
};

struct tsf_stream_cached_data {
    int buffs;
    int buffsize;
    struct tsf_stream *stream;
    unsigned int size, pos;
    unsigned char **buffer;
    unsigned int *offset;
    unsigned int *timestamp;
    unsigned int epoch;
    unsigned int hit;
    unsigned int miss;
};

static int tsf_stream_cached_read(void* v, void* ptr, unsigned int size) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    unsigned char *p = (unsigned char *)ptr;

    while (size) {
        if (d->pos >= d->size) {
            return 0;    // EOF
        }
        for (int i = 0; i < d->buffs; i++) {
            if ((d->offset[i] <= d->pos) && ((d->offset[i] + d->buffsize) > d->pos)) {
                d->timestamp[i] = d->epoch++;
                // Handle case of epoch rollover by just setting low, random epochs
                if (d->epoch == 0) {
                    for (int i = 0; i < d->buffs; i++) {
                        d->timestamp[i] = d->epoch++;
                    }
                }
                unsigned int startOffset = d->pos - d->offset[i];
                unsigned int len = d->buffsize - (d->pos % d->buffsize);
                if (len > size) {
                    len = size;
                }
                TSF_MEMCPY(p, &d->buffer[i][startOffset], len);
                size -= len;
                d->pos += len;
                p += len;
                d->hit++;
                if (size == 0) {
                    return 1;
                }
                i = -1; // Restart the for() at block 0 after postincrement
            }
        }

        int repl = 0;
        for (int i = 1; i < d->buffs; i++) {
            if (d->timestamp[i] < d->timestamp[repl]) {
                repl = i;
            }
        }
        int readOff = d->pos - (d->pos % d->buffsize);
        d->stream->seek(d->stream->data, readOff);
        d->stream->read(d->stream->data, d->buffer[repl], d->buffsize);
        d->timestamp[repl] = d->epoch++;
        d->offset[repl] = readOff;
        d->miss++;
        d->hit--; // Avoid counting this as a hit on next loop that returns data
        // Don't actually do anything yet, we'll retry the search on next loop where it will notice new data
    }
    return 1;
}

static int tsf_stream_cached_tell(void* v) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    return d->pos;
}

static int tsf_stream_cached_size(void* v) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    return d->size;
}

static int tsf_stream_cached_skip(void* v, unsigned int count) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    if ((d->pos + count) < d->size) {
        d->pos += count;
        return 1;
    }
    return 0;
}

static int tsf_stream_cached_seek(void* v, unsigned int pos) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    if (pos < d->size) {
        d->pos = pos;
        return 1;
    }
    return 0;
}

static int tsf_stream_cached_close(void* v) {
    struct tsf_stream_cached_data *d = (struct tsf_stream_cached_data*)v;
    free(d->timestamp);
    free(d->offset);
    for (int i = d->buffs - 1; i >= 0; i--) {
        free(d->buffer[i]);
    }
    free(d->buffer);
    int ret = d->stream->close(d->stream->data);
    free(d);
    return ret;
}

/*  Wraps an existing stream with a caching layer.  First create the stream you need, then
    call this to create a new stream.  Use this new stream only, and when done close() will
    close both this stream as well as the wrapped one. */
TSFDEF struct tsf_stream *tsf_stream_wrap_cached(struct tsf_stream *stream, int buffs, int buffsize, struct tsf_stream *dest) {
    struct tsf_stream_cached_data *s = (struct tsf_stream_cached_data*)TSF_MALLOC(sizeof(*s));
    s->buffs  = buffs;
    s->buffsize = buffsize;
    s->stream = stream;
    s->size = stream->size(stream->data);
    s->pos = stream->tell(stream->data);
    s->buffer = (unsigned char **)TSF_MALLOC(sizeof(*s->buffer) * buffs);
    s->offset = (unsigned int *)TSF_MALLOC(sizeof(s->offset) * buffs);
    s->timestamp = (unsigned int *)TSF_MALLOC(sizeof(s->timestamp) * buffs);
    s->epoch = 0;
    s->hit = 0;
    s->miss = 0;
    for (int i = 0; i < buffs; i++) {
        s->buffer[i] = (unsigned char *)TSF_MALLOC(buffsize);
        s->offset[i] = 0xfffffff;
        s->timestamp[i] = 0;
    }
    dest->data = (void*)s;
    dest->read = &tsf_stream_cached_read;
    dest->tell = &tsf_stream_cached_tell;
    dest->skip = &tsf_stream_cached_skip;
    dest->seek = &tsf_stream_cached_seek;
    dest->size = &tsf_stream_cached_size;
    dest->close = &tsf_stream_cached_close;
    return dest;
}


#ifndef TSF_NO_STDIO
static int tsf_stream_stdio_read(FILE* f, void* ptr, unsigned int size) {
    return (int)fread(ptr, 1, size, f);
}
static int tsf_stream_stdio_tell(FILE* f) {
    return ftell(f);
}
static int tsf_stream_stdio_size(FILE* f) {
    int p = ftell(f);
    fseek(f, 0, SEEK_END);
    int e = ftell(f);
    fseek(f, p, SEEK_SET);
    return e;
}
static int tsf_stream_stdio_skip(FILE* f, unsigned int count) {
    return !fseek(f, count, SEEK_CUR);
}
static int tsf_stream_stdio_seek(FILE* f, unsigned int count) {
    return !fseek(f, count, SEEK_SET);
}
static int tsf_stream_stdio_close(FILE* f) {
    return !fclose(f);
}
TSFDEF tsf* tsf_load_filename(const char* filename) {
    tsf* res;
    struct tsf_stream stream = { TSF_NULL, (int(*)(void*, void*, unsigned int))&tsf_stream_stdio_read, (int(*)(void*))&tsf_stream_stdio_tell, (int(*)(void*, unsigned int))&tsf_stream_stdio_skip, (int(*)(void*, unsigned int))&tsf_stream_stdio_seek, (int(*)(void*))&tsf_stream_stdio_close, (int(*)(void*))&tsf_stream_stdio_size };
#if __STDC_WANT_SECURE_LIB__
    FILE* f = TSF_NULL; fopen_s(&f, filename, "rb");
#else
    FILE* f = fopen(filename, "rb");
#endif
    if (!f) {
        //if (e) *e = TSF_FILENOTFOUND;
        return TSF_NULL;
    }
    stream.data = f;
    res = tsf_load(&stream);
    //fclose(f);
    return res;
}
#endif

struct tsf_stream_memory {
    const char* buffer;
    unsigned int total, pos;
};
static int tsf_stream_memory_read(struct tsf_stream_memory* m, void* ptr, unsigned int size) {
    if (size > m->total - m->pos) {
        size = m->total - m->pos;
    } TSF_MEMCPY(ptr, m->buffer + m->pos, size);
    m->pos += size;
    return size;
}
static int tsf_stream_memory_tell(struct tsf_stream_memory* m) {
    return m->pos;
}
static int tsf_stream_memory_size(struct tsf_stream_memory* m) {
    return m->total;
}
static int tsf_stream_memory_skip(struct tsf_stream_memory* m, unsigned int count) {
    if (m->pos + count > m->total) {
        count = m->total - m->pos;
    } m->pos += count;
    return 1;
}
static int tsf_stream_memory_seek(struct tsf_stream_memory* m, unsigned int pos) {
    if (pos > m->total) {
        return 0;
    } else {
        m->pos = pos;
    } return 1;
}
static int tsf_stream_memory_close(struct tsf_stream_memory* m) {
    TSF_FREE(m);
    return 1;
}
TSFDEF tsf* tsf_load_memory(const void* buffer, int size) {
    struct tsf_stream stream = { TSF_NULL, (int(*)(void*, void*, unsigned int))&tsf_stream_memory_read, (int(*)(void*))&tsf_stream_memory_tell, (int(*)(void*, unsigned int))&tsf_stream_memory_skip, (int(*)(void*, unsigned int))&tsf_stream_memory_seek, (int(*)(void*))&tsf_stream_memory_close, (int(*)(void*))&tsf_stream_memory_size };
    struct tsf_stream_memory* f = (struct tsf_stream_memory*)TSF_MALLOC(sizeof(struct tsf_stream_memory));
    f->pos = 0;
    f->buffer = (const char*)buffer;
    f->total = size;
    stream.data = f;
    return tsf_load(&stream);
}

enum { TSF_LOOPMODE_NONE, TSF_LOOPMODE_CONTINUOUS, TSF_LOOPMODE_SUSTAIN };

enum { TSF_SEGMENT_NONE, TSF_SEGMENT_DELAY, TSF_SEGMENT_ATTACK, TSF_SEGMENT_HOLD, TSF_SEGMENT_DECAY, TSF_SEGMENT_SUSTAIN, TSF_SEGMENT_RELEASE, TSF_SEGMENT_DONE };

struct tsf_hydra {
    struct tsf_stream *stream;
    int phdrOffset, pbagOffset, pmodOffset, pgenOffset, instOffset, ibagOffset, imodOffset, igenOffset, shdrOffset;
    int phdrNum, pbagNum, pmodNum, pgenNum, instNum, ibagNum, imodNum, igenNum, shdrNum;
};

union tsf_hydra_genamount {
    struct {
        tsf_u8 lo, hi;
    } range;
    tsf_s16 shortAmount;
    tsf_u16 wordAmount;
};
struct tsf_hydra_phdr {
    tsf_char20 presetName;
    tsf_u16 preset, bank, presetBagNdx;
    tsf_u32 library, genre, morphology;
};
struct tsf_hydra_pbag {
    tsf_u16 genNdx, modNdx;
};
struct tsf_hydra_pmod {
    tsf_u16 modSrcOper, modDestOper;
    tsf_s16 modAmount;
    tsf_u16 modAmtSrcOper, modTransOper;
};
struct tsf_hydra_pgen {
    tsf_u16 genOper;
    union tsf_hydra_genamount genAmount;
};
struct tsf_hydra_inst {
    tsf_char20 instName;
    tsf_u16 instBagNdx;
};
struct tsf_hydra_ibag {
    tsf_u16 instGenNdx, instModNdx;
};
struct tsf_hydra_imod {
    tsf_u16 modSrcOper, modDestOper;
    tsf_s16 modAmount;
    tsf_u16 modAmtSrcOper, modTransOper;
};
struct tsf_hydra_igen {
    tsf_u16 genOper;
    union tsf_hydra_genamount genAmount;
};
struct tsf_hydra_shdr {
    tsf_char20 sampleName;
    tsf_u32 start, end, startLoop, endLoop, sampleRate;
    tsf_u8 originalPitch;
    tsf_s8 pitchCorrection;
    tsf_u16 sampleLink, sampleType;
};

#define TSFR(FIELD) stream->read(stream->data, &i->FIELD, sizeof(i->FIELD));
static void tsf_hydra_read_phdr(struct tsf_hydra_phdr* i, struct tsf_stream* stream) {
    TSFR(presetName) TSFR(preset) TSFR(bank) TSFR(presetBagNdx) TSFR(library) TSFR(genre) TSFR(morphology)
}
static void tsf_hydra_read_pbag(struct tsf_hydra_pbag* i, struct tsf_stream* stream) {
    TSFR(genNdx) TSFR(modNdx)
}
//static void tsf_hydra_read_pmod(struct tsf_hydra_pmod* i, struct tsf_stream* stream) { TSFR(modSrcOper) TSFR(modDestOper) TSFR(modAmount) TSFR(modAmtSrcOper) TSFR(modTransOper) }
static void tsf_hydra_read_pgen(struct tsf_hydra_pgen* i, struct tsf_stream* stream) {
    TSFR(genOper) TSFR(genAmount)
}
static void tsf_hydra_read_inst(struct tsf_hydra_inst* i, struct tsf_stream* stream) {
    TSFR(instName) TSFR(instBagNdx)
}
static void tsf_hydra_read_ibag(struct tsf_hydra_ibag* i, struct tsf_stream* stream) {
    TSFR(instGenNdx) TSFR(instModNdx)
}
//static void tsf_hydra_read_imod(struct tsf_hydra_imod* i, struct tsf_stream* stream) { TSFR(modSrcOper) TSFR(modDestOper) TSFR(modAmount) TSFR(modAmtSrcOper) TSFR(modTransOper) }
static void tsf_hydra_read_igen(struct tsf_hydra_igen* i, struct tsf_stream* stream) {
    TSFR(genOper) TSFR(genAmount)
}
static void tsf_hydra_read_shdr(struct tsf_hydra_shdr* i, struct tsf_stream* stream) {
    TSFR(sampleName) TSFR(start) TSFR(end) TSFR(startLoop) TSFR(endLoop) TSFR(sampleRate) TSFR(originalPitch) TSFR(pitchCorrection) TSFR(sampleLink) TSFR(sampleType)
}
#undef TSFR
enum {
    phdrSizeInFile = 38, pbagSizeInFile =  4, pmodSizeInFile = 10,
    pgenSizeInFile =  4, instSizeInFile = 22, ibagSizeInFile =  4,
    imodSizeInFile = 10, igenSizeInFile =  4, shdrSizeInFile = 46
};

#define TGET(TYPE) \
static struct tsf_hydra_##TYPE *get_##TYPE(struct tsf_hydra *t, int idx, struct tsf_hydra_##TYPE *data) \
{ \
	t->stream->seek(t->stream->data, t->TYPE##Offset + TYPE##SizeInFile * idx); \
	tsf_hydra_read_##TYPE(data, t->stream); \
	return data; \
}

TGET(phdr)
TGET(pbag)
//TGET(pmod)
TGET(pgen)
TGET(inst)
TGET(ibag)
//TGET(imod)
TGET(igen)
TGET(shdr)
#undef TGET

typedef int64_t fixed32p32;
typedef int32_t fixed30p2;
typedef int32_t fixed24p8;
typedef int32_t fixed16p16;
typedef int32_t fixed8p24;



struct tsf_riffchunk {
    tsf_fourcc id;
    tsf_u32 size;
};
struct tsf_envelope {
    float delay, attack, hold, decay, sustain, release, keynumToHold, keynumToDecay;
};
struct tsf_voice_envelope {
    float level, slope;
    int samplesUntilNextSegment;
    short segment, midiVelocity;
    struct tsf_envelope parameters;
    TSF_BOOL segmentIsExponential, isAmpEnv;
};
struct tsf_voice_lowpass {
    double QInv, a0, a1, b1, b2, z1, z2;
    TSF_BOOL active;
};
struct tsf_voice_lfo {
    int samplesUntil;
    float level, delta;
};

struct tsf_region {
    int loop_mode;
    unsigned int sample_rate;
    unsigned char lokey, hikey, lovel, hivel;
    unsigned int group, offset, end, loop_start, loop_end;
    int transpose, tune, pitch_keycenter, pitch_keytrack;
    float attenuation, pan;
    struct tsf_envelope ampenv, modenv;
    int initialFilterQ, initialFilterFc;
    int modEnvToPitch, modEnvToFilterFc, modLfoToFilterFc, modLfoToVolume;
    float delayModLFO;
    int freqModLFO, modLfoToPitch;
    float delayVibLFO;
    int freqVibLFO, vibLfoToPitch;
};

struct tsf_preset {
    tsf_char20 presetName;
    tsf_u16 preset, bank;
    struct tsf_region* regions;
    int regionNum;
};

struct tsf_voice {
    int playingPreset, playingKey, playingChannel;
    struct tsf_region* region;
    double pitchRatio;
    double sourceSamplePosition;
    fixed32p32 sourceSamplePositionF32P32, loopStartF32P32, loopEndF32P32, loopSizeF32P32, pitchRatioF32P32;
    float  noteGain, panFactorLeft, panFactorRight;
    int playIndex, loopStart, loopEnd;
    struct tsf_voice_envelope ampenv, modenv;
    struct tsf_voice_lowpass lowpass;
    struct tsf_voice_lfo modlfo, viblfo;
};

struct tsf_channel {
    unsigned short presetIndex, bank, pitchWheel, midiPan, midiVolume, midiExpression, midiRPN, midiData;
    float panOffset, gainDB, pitchRange, tuning;
};

struct tsf_channels {
    void (*setupVoice)(tsf* f, struct tsf_voice* voice);
    struct tsf_channel* channels;
    int channelNum, activeChannel;
};

// Math properties of tsf_timecents2Secs* (tc2s):
//    # tc2s(a + b) = tc2s(a) * tc2s(b)
//    # tc2s(a - b) = tc2s(a) / tc2s(b)
//    # 1 / tc2s(a) = tc2s(-a)
//    # The same applies to tsf_cents2Hertz and tsf_decibelsToGain
// Path properties of tsf_decibelsToGain (db2g) and tsf_gainToDecibels (g2db)
//    # db2g(g2db(a)) = a
//    # g2db(db2g(a)) = a
static double tsf_timecents2Secsd(double timecents) {
    return TSF_POW(2.0, timecents / 1200.0);
}
static float tsf_timecents2Secsf(float timecents) {
    return TSF_POWF(2.0f, timecents / 1200.0f);
}
static float tsf_cents2Hertz(float cents) {
    return 8.176f * TSF_POWF(2.0f, cents / 1200.0f);
}
static float tsf_decibelsToGain(float db) {
    return (db > -100.f ? TSF_POWF(10.0f, db * 0.05f) : 0);
}
static float tsf_gainToDecibels(float gain) {
    return (gain <= .00001f ? -100.f : (float)(20.0 * TSF_LOG10(gain)));
}

static TSF_BOOL tsf_riffchunk_read(struct tsf_riffchunk* parent, struct tsf_riffchunk* chunk, struct tsf_stream* stream) {
    TSF_BOOL IsRiff, IsList;
    if (parent && sizeof(tsf_fourcc) + sizeof(tsf_u32) > parent->size) {
        return TSF_FALSE;
    }
    if (!stream->read(stream->data, &chunk->id, sizeof(tsf_fourcc)) || *chunk->id <= ' ' || *chunk->id >= 'z') {
        return TSF_FALSE;
    }
    if (!stream->read(stream->data, &chunk->size, sizeof(tsf_u32))) {
        return TSF_FALSE;
    }
    if (parent && sizeof(tsf_fourcc) + sizeof(tsf_u32) + chunk->size > parent->size) {
        return TSF_FALSE;
    }
    if (parent) {
        parent->size -= sizeof(tsf_fourcc) + sizeof(tsf_u32) + chunk->size;
    }
    IsRiff = TSF_FourCCEquals(chunk->id, "RIFF"), IsList = TSF_FourCCEquals(chunk->id, "LIST");
    if (IsRiff && parent) {
        return TSF_FALSE;    //not allowed
    }
    if (!IsRiff && !IsList) {
        return TSF_TRUE;    //custom type without sub type
    }
    if (!stream->read(stream->data, &chunk->id, sizeof(tsf_fourcc)) || *chunk->id <= ' ' || *chunk->id >= 'z') {
        return TSF_FALSE;
    }
    chunk->size -= sizeof(tsf_fourcc);
    return TSF_TRUE;
}

static void tsf_region_clear(struct tsf_region* i, TSF_BOOL for_relative) {
    TSF_MEMSET(i, 0, sizeof(struct tsf_region));
    i->hikey = i->hivel = 127;
    i->pitch_keycenter = 60; // C4
    if (for_relative) {
        return;
    }

    i->pitch_keytrack = 100;

    i->pitch_keycenter = -1;

    // SF2 defaults in timecents.
    i->ampenv.delay = i->ampenv.attack = i->ampenv.hold = i->ampenv.decay = i->ampenv.release = -12000.0f;
    i->modenv.delay = i->modenv.attack = i->modenv.hold = i->modenv.decay = i->modenv.release = -12000.0f;

    i->initialFilterFc = 13500;

    i->delayModLFO = -12000.0f;
    i->delayVibLFO = -12000.0f;
}

static void tsf_region_operator(struct tsf_region* region, tsf_u16 genOper, union tsf_hydra_genamount* amount, struct tsf_region* merge_region) {
    enum {
        _GEN_TYPE_MASK       = 0x0F,
        GEN_FLOAT            = 0x01,
        GEN_INT              = 0x02,
        GEN_UINT_ADD         = 0x03,
        GEN_UINT_ADD15       = 0x04,
        GEN_KEYRANGE         = 0x05,
        GEN_VELRANGE         = 0x06,
        GEN_LOOPMODE         = 0x07,
        GEN_GROUP            = 0x08,
        GEN_KEYCENTER        = 0x09,

        _GEN_LIMIT_MASK      = 0xF0,
        GEN_INT_LIMIT12K     = 0x10, //min -12000, max 12000
        GEN_INT_LIMITFC      = 0x20, //min 1500, max 13500
        GEN_INT_LIMITQ       = 0x30, //min 0, max 960
        GEN_INT_LIMIT960     = 0x40, //min -960, max 960
        GEN_INT_LIMIT16K4500 = 0x50, //min -16000, max 4500
        GEN_FLOAT_LIMIT12K5K = 0x60, //min -12000, max 5000
        GEN_FLOAT_LIMIT12K8K = 0x70, //min -12000, max 8000
        GEN_FLOAT_LIMIT1200  = 0x80, //min -1200, max 1200
        GEN_FLOAT_LIMITPAN   = 0x90, //* .001f, min -.5f, max .5f,
        GEN_FLOAT_LIMITATTN  = 0xA0, //* .1f, min 0, max 144.0
        GEN_FLOAT_MAX1000    = 0xB0, //min 0, max 1000
        GEN_FLOAT_MAX1440    = 0xC0, //min 0, max 1440

        _GEN_MAX = 59,
    };
#define _TSFREGIONOFFSET(TYPE, FIELD) (unsigned char)(((TYPE*)&((struct tsf_region*)0)->FIELD) - (TYPE*)0)
#define _TSFREGIONENVOFFSET(TYPE, ENV, FIELD) (unsigned char)(((TYPE*)&((&(((struct tsf_region*)0)->ENV))->FIELD)) - (TYPE*)0)
    static const struct {
        unsigned char mode, offset;
    } genMetas[_GEN_MAX] = {
        { GEN_UINT_ADD, _TSFREGIONOFFSET(unsigned int, offset) },                                     // 0 StartAddrsOffset
        { GEN_UINT_ADD, _TSFREGIONOFFSET(unsigned int, end) },                                        // 1 EndAddrsOffset
        { GEN_UINT_ADD, _TSFREGIONOFFSET(unsigned int, loop_start) },                                 // 2 StartloopAddrsOffset
        { GEN_UINT_ADD, _TSFREGIONOFFSET(unsigned int, loop_end) },                                   // 3 EndloopAddrsOffset
        { GEN_UINT_ADD15, _TSFREGIONOFFSET(unsigned int, offset) },                                   // 4 StartAddrsCoarseOffset
        { GEN_INT   | GEN_INT_LIMIT12K, _TSFREGIONOFFSET(int, modLfoToPitch) },                       // 5 ModLfoToPitch
        { GEN_INT   | GEN_INT_LIMIT12K, _TSFREGIONOFFSET(int, vibLfoToPitch) },                       // 6 VibLfoToPitch
        { GEN_INT   | GEN_INT_LIMIT12K, _TSFREGIONOFFSET(int, modEnvToPitch) },                       // 7 ModEnvToPitch
        { GEN_INT   | GEN_INT_LIMITFC, _TSFREGIONOFFSET(int, initialFilterFc) },                      // 8 InitialFilterFc
        { GEN_INT   | GEN_INT_LIMITQ, _TSFREGIONOFFSET(int, initialFilterQ) },                        // 9 InitialFilterQ
        { GEN_INT   | GEN_INT_LIMIT12K, _TSFREGIONOFFSET(int, modLfoToFilterFc) },                    //10 ModLfoToFilterFc
        { GEN_INT   | GEN_INT_LIMIT12K, _TSFREGIONOFFSET(int, modEnvToFilterFc) },                    //11 ModEnvToFilterFc
        { GEN_UINT_ADD15, _TSFREGIONOFFSET(unsigned int, end) },                                      //12 EndAddrsCoarseOffset
        { GEN_INT   | GEN_INT_LIMIT960, _TSFREGIONOFFSET(int, modLfoToVolume) },                      //13 ModLfoToVolume
        { 0, (0) },                                                                                   //   Unused
        { 0, (0) },                                                                                   //15 ChorusEffectsSend (unsupported)
        { 0, (0) },                                                                                   //16 ReverbEffectsSend (unsupported)
        { GEN_FLOAT | GEN_FLOAT_LIMITPAN, _TSFREGIONOFFSET(float, pan) },                             //17 Pan
        { 0, (0) },                                                                                   //   Unused
        { 0, (0) },                                                                                   //   Unused
        { 0, (0) },                                                                                   //   Unused
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONOFFSET(float, delayModLFO) },                   //21 DelayModLFO
        { GEN_INT   | GEN_INT_LIMIT16K4500, _TSFREGIONOFFSET(int, freqModLFO) },                      //22 FreqModLFO
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONOFFSET(float, delayVibLFO) },                   //23 DelayVibLFO
        { GEN_INT   | GEN_INT_LIMIT16K4500, _TSFREGIONOFFSET(int, freqVibLFO) },                      //24 FreqVibLFO
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONENVOFFSET(float, modenv, delay) },              //25 DelayModEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, modenv, attack) },             //26 AttackModEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONENVOFFSET(float, modenv, hold) },               //27 HoldModEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, modenv, decay) },              //28 DecayModEnv
        { GEN_FLOAT | GEN_FLOAT_MAX1000, _TSFREGIONENVOFFSET(float, modenv, sustain) },               //29 SustainModEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, modenv, release) },            //30 ReleaseModEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT1200, _TSFREGIONENVOFFSET(float, modenv, keynumToHold) },        //31 KeynumToModEnvHold
        { GEN_FLOAT | GEN_FLOAT_LIMIT1200, _TSFREGIONENVOFFSET(float, modenv, keynumToDecay) },       //32 KeynumToModEnvDecay
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONENVOFFSET(float, ampenv, delay) },              //33 DelayVolEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, ampenv, attack) },             //34 AttackVolEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K5K, _TSFREGIONENVOFFSET(float, ampenv, hold) },               //35 HoldVolEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, ampenv, decay) },              //36 DecayVolEnv
        { GEN_FLOAT | GEN_FLOAT_MAX1440, _TSFREGIONENVOFFSET(float, ampenv, sustain) },               //37 SustainVolEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT12K8K, _TSFREGIONENVOFFSET(float, ampenv, release) },            //38 ReleaseVolEnv
        { GEN_FLOAT | GEN_FLOAT_LIMIT1200, _TSFREGIONENVOFFSET(float, ampenv, keynumToHold) },        //39 KeynumToVolEnvHold
        { GEN_FLOAT | GEN_FLOAT_LIMIT1200, _TSFREGIONENVOFFSET(float, ampenv, keynumToDecay) },       //40 KeynumToVolEnvDecay
        { 0, (0) },                                                                                   //   Instrument (special)
        { 0, (0) },                                                                                   //   Reserved
        { GEN_KEYRANGE, (0) },                                                                        //43 KeyRange
        { GEN_VELRANGE, (0) },                                                                        //44 VelRange
        { GEN_UINT_ADD15, _TSFREGIONOFFSET(unsigned int, loop_start) },                               //45 StartloopAddrsCoarseOffset
        { 0, (0) },                                                                                   //46 Keynum (special)
        { 0, (0) },                                                                                   //47 Velocity (special)
        { GEN_FLOAT | GEN_FLOAT_LIMITATTN, _TSFREGIONOFFSET(float, attenuation) },                    //48 InitialAttenuation
        { 0, (0) },                                                                                   //   Reserved
        { GEN_UINT_ADD15, _TSFREGIONOFFSET(unsigned int, loop_end) },                                 //50 EndloopAddrsCoarseOffset
        { GEN_INT, _TSFREGIONOFFSET(int, transpose) },                                                //51 CoarseTune
        { GEN_INT, _TSFREGIONOFFSET(int, tune) },                                                     //52 FineTune
        { 0, (0) },                                                                                   //   SampleID (special)
        { GEN_LOOPMODE, _TSFREGIONOFFSET(int, loop_mode) },                                           //54 SampleModes
        { 0, (0) },                                                                                   //   Reserved
        { GEN_INT, _TSFREGIONOFFSET(int, pitch_keytrack) },                                           //56 ScaleTuning
        { GEN_GROUP, _TSFREGIONOFFSET(unsigned int, group) },                                         //57 ExclusiveClass
        { GEN_KEYCENTER, _TSFREGIONOFFSET(int, pitch_keycenter) },                                    //58 OverridingRootKey
    };
#undef _TSFREGIONOFFSET
#undef _TSFREGIONENVOFFSET
    if (amount) {
        int offset;
        if (genOper >= _GEN_MAX) {
            return;
        }
        offset = genMetas[genOper].offset;
        switch (genMetas[genOper].mode & _GEN_TYPE_MASK) {
        case GEN_FLOAT: ((float*)region)[offset]  = amount->shortAmount;     return;
        case GEN_INT: ((int*)region)[offset]  = amount->shortAmount;     return;
        case GEN_UINT_ADD: ((unsigned int*)region)[offset] += amount->shortAmount;     return;
        case GEN_UINT_ADD15: ((unsigned int*)region)[offset] += amount->shortAmount << 15; return;
        case GEN_KEYRANGE:   region->lokey = amount->range.lo; region->hikey = amount->range.hi; return;
        case GEN_VELRANGE:   region->lovel = amount->range.lo; region->hivel = amount->range.hi; return;
        case GEN_LOOPMODE:   region->loop_mode       = ((amount->wordAmount & 3) == 3 ? TSF_LOOPMODE_SUSTAIN : ((amount->wordAmount & 3) == 1 ? TSF_LOOPMODE_CONTINUOUS : TSF_LOOPMODE_NONE)); return;
        case GEN_GROUP:      region->group           = amount->wordAmount;  return;
        case GEN_KEYCENTER:  region->pitch_keycenter = amount->shortAmount; return;
        }
    } else { //merge regions and clamp values
        for (genOper = 0; genOper != _GEN_MAX; genOper++) {
            int offset = genMetas[genOper].offset;
            switch (genMetas[genOper].mode & _GEN_TYPE_MASK) {
            case GEN_FLOAT: {
                float *val = &((float*)region)[offset], vfactor, vmin, vmax;
                *val += ((float*)merge_region)[offset];
                switch (genMetas[genOper].mode & _GEN_LIMIT_MASK) {
                case GEN_FLOAT_LIMIT12K5K: vfactor =   1.0f; vmin = -12000.0f; vmax = 5000.0f; break;
                case GEN_FLOAT_LIMIT12K8K: vfactor =   1.0f; vmin = -12000.0f; vmax = 8000.0f; break;
                case GEN_FLOAT_LIMIT1200:  vfactor =   1.0f; vmin =  -1200.0f; vmax = 1200.0f; break;
                case GEN_FLOAT_LIMITPAN:   vfactor = 0.001f; vmin =     -0.5f; vmax =    0.5f; break;
                case GEN_FLOAT_LIMITATTN:  vfactor =   0.1f; vmin =      0.0f; vmax =  144.0f; break;
                case GEN_FLOAT_MAX1000:    vfactor =   1.0f; vmin =      0.0f; vmax = 1000.0f; break;
                case GEN_FLOAT_MAX1440:    vfactor =   1.0f; vmin =      0.0f; vmax = 1440.0f; break;
                default: continue;
                }
                *val *= vfactor;
                if (*val < vmin) {
                    *val = vmin;
                } else if (*val > vmax) {
                    *val = vmax;
                }
                continue;
            }
            case GEN_INT: {
                int *val = &((int*)region)[offset], vmin, vmax;
                *val += ((int*)merge_region)[offset];
                switch (genMetas[genOper].mode & _GEN_LIMIT_MASK) {
                case GEN_INT_LIMIT12K:     vmin = -12000; vmax = 12000; break;
                case GEN_INT_LIMITFC:      vmin =   1500; vmax = 13500; break;
                case GEN_INT_LIMITQ:       vmin =      0; vmax =   960; break;
                case GEN_INT_LIMIT960:     vmin =   -960; vmax =   960; break;
                case GEN_INT_LIMIT16K4500: vmin = -16000; vmax =  4500; break;
                default: continue;
                }
                if (*val < vmin) {
                    *val = vmin;
                } else if (*val > vmax) {
                    *val = vmax;
                }
                continue;
            }
            case GEN_UINT_ADD: {
                ((unsigned int*)region)[offset] += ((unsigned int*)merge_region)[offset];
                continue;
            }
            }
        }
    }
}

static void tsf_region_envtosecs(struct tsf_envelope* p, TSF_BOOL sustainIsGain) {
    // EG times need to be converted from timecents to seconds.
    // Pin very short EG segments.  Timecents don't get to zero, and our EG is
    // happier with zero values.
    p->delay   = (p->delay   < -11950.0f ? 0.0f : tsf_timecents2Secsf(p->delay));
    p->attack  = (p->attack  < -11950.0f ? 0.0f : tsf_timecents2Secsf(p->attack));
    p->release = (p->release < -11950.0f ? 0.0f : tsf_timecents2Secsf(p->release));

    // If we have dynamic hold or decay times depending on key number we need
    // to keep the values in timecents so we can calculate it during startNote
    if (!p->keynumToHold) {
        p->hold  = (p->hold  < -11950.0f ? 0.0f : tsf_timecents2Secsf(p->hold));
    }
    if (!p->keynumToDecay) {
        p->decay = (p->decay < -11950.0f ? 0.0f : tsf_timecents2Secsf(p->decay));
    }

    if (p->sustain < 0.0f) {
        p->sustain = 0.0f;
    } else if (sustainIsGain) {
        p->sustain = tsf_decibelsToGain(-p->sustain / 10.0f);
    } else {
        p->sustain = 1.0f - (p->sustain / 1000.0f);
    }
}

static void tsf_load_preset(const tsf* res, struct tsf_hydra *hydra, int presetToLoad) {
    enum { GenInstrument = 41, GenKeyRange = 43, GenVelRange = 44, GenSampleID = 53 };
    // Read each preset.
    struct tsf_hydra_phdr phdr;
    int phdrIdx, phdrMaxIdx;
    for (phdrIdx = presetToLoad, get_phdr(hydra, phdrIdx, &phdr), phdrMaxIdx = presetToLoad + 1 /*hydra->phdrNum - 1*/; phdrIdx != phdrMaxIdx; phdrIdx++, get_phdr(hydra, phdrIdx, &phdr)) {
        int sortedIndex = 0, region_index = 0;
        struct tsf_hydra_phdr otherPhdr;
        int otherPhdrIdx;
        struct tsf_preset* preset;
        struct tsf_region globalRegion;
        for (otherPhdrIdx = 0, get_phdr(hydra, otherPhdrIdx, &otherPhdr); otherPhdrIdx != phdrMaxIdx; otherPhdrIdx++, get_phdr(hydra, otherPhdrIdx, &otherPhdr)) {
            if (otherPhdrIdx == phdrIdx || otherPhdr.bank > phdr.bank) {
                continue;
            } else if (otherPhdr.bank < phdr.bank) {
                sortedIndex++;
            } else if (otherPhdr.preset > phdr.preset) {
                continue;
            } else if (otherPhdr.preset < phdr.preset) {
                sortedIndex++;
            } else if (otherPhdrIdx < phdrIdx) {
                sortedIndex++;
            }
        }

        preset = &res->presets[sortedIndex];
        TSF_MEMCPY(preset->presetName, phdr.presetName, sizeof(preset->presetName));
        preset->presetName[sizeof(preset->presetName) - 1] = '\0'; //should be zero terminated in source file but make sure
        preset->bank = phdr.bank;
        preset->preset = phdr.preset;
        preset->regionNum = 0;

        struct tsf_hydra_phdr phdrNext;
        get_phdr(hydra, phdrIdx + 1, &phdrNext);

        //count regions covered by this preset
        struct tsf_hydra_pbag pbag;
        int pbagIdx, pbagEndIdx;
        for (pbagIdx = phdr.presetBagNdx, get_pbag(hydra, pbagIdx, &pbag), pbagEndIdx = phdrNext.presetBagNdx; pbagIdx != pbagEndIdx; pbagIdx++, get_pbag(hydra, pbagIdx, &pbag)) {
            struct tsf_hydra_pbag pbagNext;
            unsigned char plokey = 0, phikey = 127, plovel = 0, phivel = 127;
            get_pbag(hydra, pbagIdx + 1, &pbagNext);
            struct tsf_hydra_pgen pgen;
            int pgenIdx, pgenEndIdx;
            for (pgenIdx = pbag.genNdx, get_pgen(hydra, pgenIdx, &pgen), pgenEndIdx = pbagNext.genNdx; pgenIdx != pgenEndIdx; pgenIdx++, get_pgen(hydra, pgenIdx, &pgen)) {
                if (pgen.genOper == GenKeyRange) {
                    plokey = pgen.genAmount.range.lo;
                    phikey = pgen.genAmount.range.hi;
                    continue;
                }
                if (pgen.genOper == GenVelRange) {
                    plovel = pgen.genAmount.range.lo;
                    phivel = pgen.genAmount.range.hi;
                    continue;
                }
                if (pgen.genOper != GenInstrument) {
                    continue;
                }
                if (pgen.genAmount.wordAmount >= hydra->instNum) {
                    continue;
                }
                struct tsf_hydra_inst inst, instNext;
                get_inst(hydra, pgen.genAmount.wordAmount, &inst);
                get_inst(hydra, pgen.genAmount.wordAmount + 1, &instNext);
                struct tsf_hydra_ibag ibag;
                int ibagIdx, ibagEndIdx;
                for (ibagIdx = inst.instBagNdx, get_ibag(hydra, ibagIdx, &ibag), ibagEndIdx = instNext.instBagNdx; ibagIdx != ibagEndIdx; ibagIdx++, get_ibag(hydra, ibagIdx, &ibag)) {
                    struct tsf_hydra_ibag ibagNext;
                    get_ibag(hydra, ibagIdx + 1, &ibagNext);
                    struct tsf_hydra_igen igen;
                    int igenIdx, igenEndIdx;
                    unsigned char ilokey = 0, ihikey = 127, ilovel = 0, ihivel = 127;
                    for (igenIdx = ibag.instGenNdx, get_igen(hydra, igenIdx, &igen), igenEndIdx = ibagNext.instGenNdx; igenIdx != igenEndIdx; igenIdx++, get_igen(hydra, igenIdx, &igen)) {
                        if (igen.genOper == GenKeyRange) {
                            ilokey = igen.genAmount.range.lo;
                            ihikey = igen.genAmount.range.hi;
                            continue;
                        }
                        if (igen.genOper == GenVelRange) {
                            ilovel = igen.genAmount.range.lo;
                            ihivel = igen.genAmount.range.hi;
                            continue;
                        }
                        if (igen.genOper == GenSampleID && ihikey >= plokey && ilokey <= phikey && ihivel >= plovel && ilovel <= phivel) {
                            preset->regionNum++;
                        }
                    }
                }
            }
        }

        preset->regions = (struct tsf_region*)TSF_MALLOC(preset->regionNum * sizeof(struct tsf_region));
        tsf_region_clear(&globalRegion, TSF_TRUE);

        // Zones.
        for (pbagIdx = phdr.presetBagNdx, get_pbag(hydra, pbagIdx, &pbag), pbagEndIdx = phdrNext.presetBagNdx; pbagIdx != pbagEndIdx; pbagIdx++, get_pbag(hydra, pbagIdx, &pbag)) {
            struct tsf_region presetRegion = globalRegion;
            int hadGenInstrument = 0;
            struct tsf_hydra_pbag pbagNext;
            get_pbag(hydra, pbagIdx + 1, &pbagNext);
            struct tsf_hydra_pgen pgen;
            int pgenIdx, pgenEndIdx;

            // Generators.
            for (pgenIdx = pbag.genNdx, get_pgen(hydra, pgenIdx, &pgen), pgenEndIdx = pbagNext.genNdx; pgenIdx != pgenEndIdx; pgenIdx++, get_pgen(hydra, pgenIdx, &pgen)) {
                // Instrument.
                if (pgen.genOper == GenInstrument) {
                    struct tsf_region instRegion;
                    tsf_u16 whichInst = pgen.genAmount.wordAmount;
                    if (whichInst >= hydra->instNum) {
                        continue;
                    }

                    tsf_region_clear(&instRegion, TSF_FALSE);
                    struct tsf_hydra_inst inst, instNext;
                    get_inst(hydra, whichInst, &inst);
                    get_inst(hydra, whichInst + 1, &instNext);
                    struct tsf_hydra_ibag ibag;
                    int ibagIdx, ibagEndIdx;
                    for (ibagIdx = inst.instBagNdx, get_ibag(hydra, ibagIdx, &ibag), ibagEndIdx = instNext.instBagNdx; ibagIdx != ibagEndIdx; ibagIdx++, get_ibag(hydra, ibagIdx, &ibag)) {
                        // Generators.
                        struct tsf_region zoneRegion = instRegion;
                        int hadSampleID = 0;
                        struct tsf_hydra_ibag ibagNext;
                        get_ibag(hydra, ibagIdx + 1, &ibagNext);
                        struct tsf_hydra_igen igen;
                        int igenIdx, igenEndIdx;
                        for (igenIdx = ibag.instGenNdx, get_igen(hydra, igenIdx, &igen), igenEndIdx = ibagNext.instGenNdx; igenIdx != igenEndIdx; igenIdx++, get_igen(hydra, igenIdx, &igen)) {
                            if (igen.genOper == GenSampleID) {
                                struct tsf_hydra_shdr shdr;
                                get_shdr(hydra, igen.genAmount.wordAmount, &shdr);

                                //preset region key and vel ranges are a filter for the zone regions
                                if (zoneRegion.hikey < presetRegion.lokey || zoneRegion.lokey > presetRegion.hikey) {
                                    continue;
                                }
                                if (zoneRegion.hivel < presetRegion.lovel || zoneRegion.lovel > presetRegion.hivel) {
                                    continue;
                                }
                                if (presetRegion.lokey > zoneRegion.lokey) {
                                    zoneRegion.lokey = presetRegion.lokey;
                                }
                                if (presetRegion.hikey < zoneRegion.hikey) {
                                    zoneRegion.hikey = presetRegion.hikey;
                                }
                                if (presetRegion.lovel > zoneRegion.lovel) {
                                    zoneRegion.lovel = presetRegion.lovel;
                                }
                                if (presetRegion.hivel < zoneRegion.hivel) {
                                    zoneRegion.hivel = presetRegion.hivel;
                                }

                                //sum regions
                                tsf_region_operator(&zoneRegion, 0, TSF_NULL, &presetRegion);

                                // EG times need to be converted from timecents to seconds.
                                tsf_region_envtosecs(&zoneRegion.ampenv, TSF_TRUE);
                                tsf_region_envtosecs(&zoneRegion.modenv, TSF_FALSE);

                                // LFO times need to be converted from timecents to seconds.
                                zoneRegion.delayModLFO = (zoneRegion.delayModLFO < -11950.0f ? 0.0f : tsf_timecents2Secsf(zoneRegion.delayModLFO));
                                zoneRegion.delayVibLFO = (zoneRegion.delayVibLFO < -11950.0f ? 0.0f : tsf_timecents2Secsf(zoneRegion.delayVibLFO));

                                // Fixup sample positions

                                get_shdr(hydra, igen.genAmount.wordAmount, &shdr);
                                zoneRegion.offset += shdr.start;
                                zoneRegion.end += shdr.end;
                                zoneRegion.loop_start += shdr.startLoop;
                                zoneRegion.loop_end += shdr.endLoop;
                                if (shdr.endLoop > 0) {
                                    zoneRegion.loop_end -= 1;
                                }
                                if (zoneRegion.pitch_keycenter == -1) {
                                    zoneRegion.pitch_keycenter = shdr.originalPitch;
                                }
                                zoneRegion.tune += shdr.pitchCorrection;
                                zoneRegion.sample_rate = shdr.sampleRate;
                                if (zoneRegion.end && zoneRegion.end < res->fontSampleCount) {
                                    zoneRegion.end++;
                                } else {
                                    zoneRegion.end = res->fontSampleCount;
                                }

                                preset->regions[region_index] = zoneRegion;
                                region_index++;
                                hadSampleID = 1;
                            } else {
                                tsf_region_operator(&zoneRegion, igen.genOper, &igen.genAmount, TSF_NULL);
                            }
                        }

                        // Handle instrument's global zone.
                        if (ibagIdx == inst.instBagNdx && !hadSampleID) {
                            instRegion = zoneRegion;
                        }

                        // Modulators (TODO)
                        //if (ibag->instModNdx < ibag[1].instModNdx) addUnsupportedOpcode("any modulator");
                    }
                    hadGenInstrument = 1;
                } else {
                    tsf_region_operator(&presetRegion, pgen.genOper, &pgen.genAmount, TSF_NULL);
                }
            }

            // Modulators (TODO)
            //if (pbag->modNdx < pbag[1].modNdx) addUnsupportedOpcode("any modulator");

            // Handle preset's global zone.
            if (pbagIdx == phdr.presetBagNdx && !hadGenInstrument) {
                globalRegion = presetRegion;
            }
        }
    }
}

static void tsf_load_samples(int *fontSamplesOffset, unsigned int* fontSampleCount, struct tsf_riffchunk *chunkSmpl, struct tsf_stream* stream) {
    // Read sample data into float format buffer.
    unsigned int samplesLeft;
    samplesLeft = *fontSampleCount = chunkSmpl->size / sizeof(short);
    *fontSamplesOffset = stream->tell(stream->data);
    stream->skip(stream->data, samplesLeft * sizeof(short));
}

static void tsf_voice_envelope_nextsegment(struct tsf_voice_envelope* e, short active_segment, float outSampleRate) {
    switch (active_segment) {
    case TSF_SEGMENT_NONE:
        e->samplesUntilNextSegment = (int)(e->parameters.delay * outSampleRate);
        if (e->samplesUntilNextSegment > 0) {
            e->segment = TSF_SEGMENT_DELAY;
            e->segmentIsExponential = TSF_FALSE;
            e->level = 0.0;
            e->slope = 0.0;
            return;
        }
    /* fall through */
    case TSF_SEGMENT_DELAY:
        e->samplesUntilNextSegment = (int)(e->parameters.attack * outSampleRate);
        if (e->samplesUntilNextSegment > 0) {
            if (!e->isAmpEnv) {
                //mod env attack duration scales with velocity (velocity of 1 is full duration, max velocity is 0.125 times duration)
                e->samplesUntilNextSegment = (int)(e->parameters.attack * ((145 - e->midiVelocity) / 144.0f) * outSampleRate);
            }
            e->segment = TSF_SEGMENT_ATTACK;
            e->segmentIsExponential = TSF_FALSE;
            e->level = 0.0f;
            e->slope = 1.0f / e->samplesUntilNextSegment;
            return;
        }
    /* fall through */
    case TSF_SEGMENT_ATTACK:
        e->samplesUntilNextSegment = (int)(e->parameters.hold * outSampleRate);
        if (e->samplesUntilNextSegment > 0) {
            e->segment = TSF_SEGMENT_HOLD;
            e->segmentIsExponential = TSF_FALSE;
            e->level = 1.0f;
            e->slope = 0.0f;
            return;
        }
    /* fall through */
    case TSF_SEGMENT_HOLD:
        e->samplesUntilNextSegment = (int)(e->parameters.decay * outSampleRate);
        if (e->samplesUntilNextSegment > 0) {
            e->segment = TSF_SEGMENT_DECAY;
            e->level = 1.0f;
            if (e->isAmpEnv) {
                // I don't truly understand this; just following what LinuxSampler does.
                float mysterySlope = -9.226f / e->samplesUntilNextSegment;
                e->slope = TSF_EXPF(mysterySlope);
                e->segmentIsExponential = TSF_TRUE;
                if (e->parameters.sustain > 0.0f) {
                    // Again, this is following LinuxSampler's example, which is similar to
                    // SF2-style decay, where "decay" specifies the time it would take to
                    // get to zero, not to the sustain level.  The SFZ spec is not that
                    // specific about what "decay" means, so perhaps it's really supposed
                    // to specify the time to reach the sustain level.
                    e->samplesUntilNextSegment = (int)(TSF_LOG(e->parameters.sustain) / mysterySlope);
                }
            } else {
                e->slope = -1.0f / e->samplesUntilNextSegment;
                e->samplesUntilNextSegment = (int)(e->parameters.decay * (1.0f - e->parameters.sustain) * outSampleRate);
                e->segmentIsExponential = TSF_FALSE;
            }
            return;
        }
    /* fall through */
    case TSF_SEGMENT_DECAY:
        e->segment = TSF_SEGMENT_SUSTAIN;
        e->level = e->parameters.sustain;
        e->slope = 0.0f;
        e->samplesUntilNextSegment = 0x7FFFFFFF;
        e->segmentIsExponential = TSF_FALSE;
        return;
    case TSF_SEGMENT_SUSTAIN:
        e->segment = TSF_SEGMENT_RELEASE;
        e->samplesUntilNextSegment = (int)((e->parameters.release <= 0 ? TSF_FASTRELEASETIME : e->parameters.release) * outSampleRate);
        if (e->isAmpEnv) {
            // I don't truly understand this; just following what LinuxSampler does.
            float mysterySlope = -9.226f / e->samplesUntilNextSegment;
            e->slope = TSF_EXPF(mysterySlope);
            e->segmentIsExponential = TSF_TRUE;
        } else {
            e->slope = -e->level / e->samplesUntilNextSegment;
            e->segmentIsExponential = TSF_FALSE;
        }
        return;
    case TSF_SEGMENT_RELEASE:
    default:
        e->segment = TSF_SEGMENT_DONE;
        e->segmentIsExponential = TSF_FALSE;
        e->level = e->slope = 0.0f;
        e->samplesUntilNextSegment = 0x7FFFFFF;
    }
}

static void tsf_voice_envelope_setup(struct tsf_voice_envelope* e, struct tsf_envelope* new_parameters, int midiNoteNumber, short midiVelocity, TSF_BOOL isAmpEnv, float outSampleRate) {
    e->parameters = *new_parameters;
    if (e->parameters.keynumToHold) {
        e->parameters.hold += e->parameters.keynumToHold * (60.0f - midiNoteNumber);
        e->parameters.hold = (e->parameters.hold < -10000.0f ? 0.0f : tsf_timecents2Secsf(e->parameters.hold));
    }
    if (e->parameters.keynumToDecay) {
        e->parameters.decay += e->parameters.keynumToDecay * (60.0f - midiNoteNumber);
        e->parameters.decay = (e->parameters.decay < -10000.0f ? 0.0f : tsf_timecents2Secsf(e->parameters.decay));
    }
    e->midiVelocity = midiVelocity;
    e->isAmpEnv = isAmpEnv;
    tsf_voice_envelope_nextsegment(e, TSF_SEGMENT_NONE, outSampleRate);
}

static void tsf_voice_envelope_process(struct tsf_voice_envelope* e, int numSamples, float outSampleRate) {
    if (e->slope) {
        if (e->segmentIsExponential) {
            e->level *= TSF_POWF(e->slope, (float)numSamples);
        } else {
            e->level += (e->slope * numSamples);
        }
    }
    if ((e->samplesUntilNextSegment -= numSamples) <= 0) {
        tsf_voice_envelope_nextsegment(e, e->segment, outSampleRate);
    }
}

static void tsf_voice_lowpass_setup(struct tsf_voice_lowpass* e, float Fc) {
    // Lowpass filter from http://www.earlevel.com/main/2012/11/26/biquad-c-source-code/
    double K = TSF_TAN(TSF_PI * Fc), KK = K * K;
    double norm = 1 / (1 + K * e->QInv + KK);
    e->a0 = KK * norm;
    e->a1 = 2 * e->a0;
    e->b1 = 2 * (KK - 1) * norm;
    e->b2 = (1 - K * e->QInv + KK) * norm;
}

static float tsf_voice_lowpass_process(struct tsf_voice_lowpass* e, double In) {
    double Out = In * e->a0 + e->z1; e->z1 = In * e->a1 + e->z2 - e->b1 * Out; e->z2 = In * e->a0 - e->b2 * Out; return (float)Out;
}

static void tsf_voice_lfo_setup(struct tsf_voice_lfo* e, float delay, int freqCents, float outSampleRate) {
    e->samplesUntil = (int)(delay * outSampleRate);
    e->delta = (4.0f * tsf_cents2Hertz((float)freqCents) / outSampleRate);
    e->level = 0;
}

static void tsf_voice_lfo_process(struct tsf_voice_lfo* e, int blockSamples) {
    if (e->samplesUntil > blockSamples) {
        e->samplesUntil -= blockSamples;
        return;
    }
    e->level += e->delta * blockSamples;
    if (e->level >  1.0f) {
        e->delta = -e->delta;
        e->level =  2.0f - e->level;
    } else if (e->level < -1.0f) {
        e->delta = -e->delta;
        e->level = -2.0f - e->level;
    }
}

static void tsf_voice_kill(struct tsf_voice* v) {
    v->playingPreset = -1;
}

static void tsf_voice_end(struct tsf_voice* v, float outSampleRate) {
    tsf_voice_envelope_nextsegment(&v->ampenv, TSF_SEGMENT_SUSTAIN, outSampleRate);
    tsf_voice_envelope_nextsegment(&v->modenv, TSF_SEGMENT_SUSTAIN, outSampleRate);
    if (v->region->loop_mode == TSF_LOOPMODE_SUSTAIN) {
        // Continue playing, but stop looping.
        v->loopEnd = v->loopStart;
        v->loopSizeF32P32 = 0;
    }
}

static void tsf_voice_endquick(struct tsf_voice* v, float outSampleRate) {
    v->ampenv.parameters.release = 0.0f; tsf_voice_envelope_nextsegment(&v->ampenv, TSF_SEGMENT_SUSTAIN, outSampleRate);
    v->modenv.parameters.release = 0.0f; tsf_voice_envelope_nextsegment(&v->modenv, TSF_SEGMENT_SUSTAIN, outSampleRate);
}

static void tsf_voice_calcpitchratio(struct tsf_voice* v, float pitchShift, float outSampleRate) {
    double note = v->playingKey + v->region->transpose + v->region->tune / 100.0;
    double adjustedPitch = (note - v->region->pitch_keycenter) * v->region->pitch_keytrack;
    if (pitchShift) {
        adjustedPitch += adjustedPitch * 100.0f;
    }
    v->pitchRatio = v->region->sample_rate * tsf_timecents2Secsd(adjustedPitch) / outSampleRate;
}

short tsf_read_short_cached(tsf *f, int pos) {
    static int hits = 0;
    static int misses = 0;
    //	static int call =0;
    //	call++;
    //	if ((call % 88000) ==0) printf("Hit: %d, Miss: %d, Ratio: %f\n", hits, misses, (double)hits/(double)(misses+hits));

    for (int i = 0; i < TSF_BUFFS; i++) {
        if ((f->offset[i] <= pos) && ((f->offset[i] + TSF_BUFFSIZE) > pos)) {
            f->timestamp[i] = f->epoch++;
            if (f->epoch == 0) {
                for (int i = 0; i < TSF_BUFFS; i++) {
                    f->timestamp[i] = f->epoch++;
                }
            }
            hits++;
            return f->buffer[i][pos - f->offset[i]];
        }
    }
    int repl = 0;
    for (int i = 1; i < TSF_BUFFS; i++) {
        if (f->timestamp[i] < f->timestamp[repl]) {
            repl = i;
        }
    }
    int readOff = pos - (pos % TSF_BUFFSIZE);
    // for (int i=0; i<TSF_BUFFSIZE; i++) { f->buffer[repl][i] = i; }
    f->hydra->stream->seek(f->hydra->stream->data, readOff * sizeof(short));
    f->hydra->stream->read(f->hydra->stream->data, f->buffer[repl], TSF_BUFFSIZE * sizeof(short));
    //static uint32_t *bp = NULL; if (!bp) bp = (uint32_t*)malloc(512);
    //printf("off=%08x, buff=%p, len=%08x\n", readOff * sizeof(short), bp, TSF_BUFFSIZE); spi_flash_read(0x0000, bp, 512/4-4) ;
    f->timestamp[repl] = f->epoch++;
    f->offset[repl] = readOff;
    misses++;
    //	fprintf(stderr, "buffer[%d][%d-%d = %d]\n", repl, pos, readOff, pos - readOff);
    return f->buffer[repl][pos - readOff];
}

static void tsf_voice_render(tsf* f, struct tsf_voice* v, float* outputBuffer, int numSamples) {
    struct tsf_region* region = v->region;
    float* outL = outputBuffer;
    float* outR = (f->outputmode == TSF_STEREO_UNWEAVED ? outL + numSamples : TSF_NULL);

    // Cache some values, to give them at least some chance of ending up in registers.
    TSF_BOOL updateModEnv = (region->modEnvToPitch || region->modEnvToFilterFc);
    TSF_BOOL updateModLFO = (v->modlfo.delta && (region->modLfoToPitch || region->modLfoToFilterFc || region->modLfoToVolume));
    TSF_BOOL updateVibLFO = (v->viblfo.delta && (region->vibLfoToPitch));
    TSF_BOOL isLooping    = (v->loopStart < v->loopEnd);
    unsigned int tmpLoopStart = v->loopStart, tmpLoopEnd = v->loopEnd;
    double tmpSampleEndDbl = (double)region->end, tmpLoopEndDbl = (double)tmpLoopEnd + 1.0;
    double tmpSourceSamplePosition = v->sourceSamplePosition;
    struct tsf_voice_lowpass tmpLowpass = v->lowpass;

    TSF_BOOL dynamicLowpass = (region->modLfoToFilterFc || region->modEnvToFilterFc);
    float tmpSampleRate = f->outSampleRate, tmpInitialFilterFc, tmpModLfoToFilterFc, tmpModEnvToFilterFc;

    TSF_BOOL dynamicPitchRatio = (region->modLfoToPitch || region->modEnvToPitch || region->vibLfoToPitch);
    double pitchRatio;
    float tmpModLfoToPitch, tmpVibLfoToPitch, tmpModEnvToPitch;

    TSF_BOOL dynamicGain = (region->modLfoToVolume != 0);
    float noteGain = 0, tmpModLfoToVolume;

    if (dynamicLowpass) {
        tmpInitialFilterFc = (float)region->initialFilterFc, tmpModLfoToFilterFc = (float)region->modLfoToFilterFc, tmpModEnvToFilterFc = (float)region->modEnvToFilterFc;
    } else {
        tmpInitialFilterFc = 0, tmpModLfoToFilterFc = 0, tmpModEnvToFilterFc = 0;
    }

    if (dynamicPitchRatio) {
        pitchRatio = 0, tmpModLfoToPitch = (float)region->modLfoToPitch, tmpVibLfoToPitch = (float)region->vibLfoToPitch, tmpModEnvToPitch = (float)region->modEnvToPitch;
    } else {
        pitchRatio = v->pitchRatio, tmpModLfoToPitch = 0, tmpVibLfoToPitch = 0, tmpModEnvToPitch = 0;
    }

    if (dynamicGain) {
        tmpModLfoToVolume = (float)region->modLfoToVolume * 0.1f;
    } else {
        noteGain = v->noteGain, tmpModLfoToVolume = 0;
    }

    while (numSamples) {
        float gainMono, gainLeft, gainRight;
        int blockSamples = (numSamples > TSF_RENDER_EFFECTSAMPLEBLOCK ? TSF_RENDER_EFFECTSAMPLEBLOCK : numSamples);
        numSamples -= blockSamples;

        if (dynamicLowpass) {
            float fres = tmpInitialFilterFc + v->modlfo.level * tmpModLfoToFilterFc + v->modenv.level * tmpModEnvToFilterFc;
            float lowpassFc = (fres <= 13500 ? tsf_cents2Hertz(fres) / tmpSampleRate : 1.0f);
            tmpLowpass.active = (lowpassFc < 0.499f);
            if (tmpLowpass.active) {
                tsf_voice_lowpass_setup(&tmpLowpass, lowpassFc);
            }
        }

        if (dynamicPitchRatio) {
            pitchRatio = v->pitchRatio * tsf_timecents2Secsd(v->modlfo.level * tmpModLfoToPitch + v->viblfo.level * tmpVibLfoToPitch + v->modenv.level * tmpModEnvToPitch);
        }

        if (dynamicGain) {
            noteGain = v->noteGain * tsf_decibelsToGain(v->modlfo.level * tmpModLfoToVolume);
        }

        gainMono = noteGain * v->ampenv.level;

        // Update EG.
        tsf_voice_envelope_process(&v->ampenv, blockSamples, tmpSampleRate);
        if (updateModEnv) {
            tsf_voice_envelope_process(&v->modenv, blockSamples, tmpSampleRate);
        }

        // Update LFOs.
        if (updateModLFO) {
            tsf_voice_lfo_process(&v->modlfo, blockSamples);
        }
        if (updateVibLFO) {
            tsf_voice_lfo_process(&v->viblfo, blockSamples);
        }

        switch (f->outputmode) {
        case TSF_STEREO_INTERLEAVED:
            gainLeft = gainMono * v->panFactorLeft, gainRight = gainMono * v->panFactorRight;
            while (blockSamples-- && tmpSourceSamplePosition < tmpSampleEndDbl) {
                unsigned int pos = (unsigned int)tmpSourceSamplePosition, nextPos = (pos >= tmpLoopEnd && isLooping ? tmpLoopStart : pos + 1);
                float inputPos, inputNextPos;
                inputPos = (float)(tsf_read_short_cached(f, pos) / 32767.0);
                inputNextPos = (float)(tsf_read_short_cached(f, nextPos) / 32767.0);
                // Simple linear interpolation.
                float alpha = (float)(tmpSourceSamplePosition - pos), val = (inputPos * (1.0f - alpha) + inputNextPos * alpha);

                // Low-pass filter.
                if (tmpLowpass.active) {
                    val = tsf_voice_lowpass_process(&tmpLowpass, val);
                }

                *outL++ += val * gainLeft;
                *outL++ += val * gainRight;

                // Next sample.
                tmpSourceSamplePosition += pitchRatio;
                if (tmpSourceSamplePosition >= tmpLoopEndDbl && isLooping) {
                    tmpSourceSamplePosition -= (tmpLoopEnd - tmpLoopStart + 1.0);
                }
            }
            break;

        case TSF_STEREO_UNWEAVED:
            gainLeft = gainMono * v->panFactorLeft, gainRight = gainMono * v->panFactorRight;
            while (blockSamples-- && tmpSourceSamplePosition < tmpSampleEndDbl) {
                unsigned int pos = (unsigned int)tmpSourceSamplePosition, nextPos = (pos >= tmpLoopEnd && isLooping ? tmpLoopStart : pos + 1);
                float inputPos, inputNextPos;
                inputPos = (float)(tsf_read_short_cached(f, pos) / 32767.0);
                inputNextPos = (float)(tsf_read_short_cached(f, nextPos) / 32767.0);

                // Simple linear interpolation.
                float alpha = (float)(tmpSourceSamplePosition - pos), val = (inputPos * (1.0f - alpha) + inputNextPos * alpha);

                // Low-pass filter.
                if (tmpLowpass.active) {
                    val = tsf_voice_lowpass_process(&tmpLowpass, val);
                }

                *outL++ += val * gainLeft;
                *outR++ += val * gainRight;

                // Next sample.
                tmpSourceSamplePosition += pitchRatio;
                if (tmpSourceSamplePosition >= tmpLoopEndDbl && isLooping) {
                    tmpSourceSamplePosition -= (tmpLoopEnd - tmpLoopStart + 1.0);
                }
            }
            break;

        case TSF_MONO:
            while (blockSamples-- && tmpSourceSamplePosition < tmpSampleEndDbl) {
                unsigned int pos = (unsigned int)tmpSourceSamplePosition, nextPos = (pos >= tmpLoopEnd && isLooping ? tmpLoopStart : pos + 1);
                float inputPos, inputNextPos;
                inputPos = (float)(tsf_read_short_cached(f, pos) / 32767.0);
                inputNextPos = (float)(tsf_read_short_cached(f, nextPos) / 32767.0);

                // Simple linear interpolation.
                float alpha = (float)(tmpSourceSamplePosition - pos), val = (inputPos * (1.0f - alpha) + inputNextPos * alpha);

                // Low-pass filter.
                if (tmpLowpass.active) {
                    val = tsf_voice_lowpass_process(&tmpLowpass, val);
                }

                *outL++ += val * gainMono;

                // Next sample.
                tmpSourceSamplePosition += pitchRatio;
                if (tmpSourceSamplePosition >= tmpLoopEndDbl && isLooping) {
                    tmpSourceSamplePosition -= (tmpLoopEnd - tmpLoopStart + 1.0);
                }
            }
            break;
        }

        if (tmpSourceSamplePosition >= tmpSampleEndDbl || v->ampenv.segment == TSF_SEGMENT_DONE) {
            tsf_voice_kill(v);
            return;
        }
    }

    v->sourceSamplePosition = tmpSourceSamplePosition;
    if (tmpLowpass.active || dynamicLowpass) {
        v->lowpass = tmpLowpass;
    }
}


//void DumpF32P32(char *name, long long x) {
//  printf("%s = %08x.%08x\n", name, (int32_t)((x>>32)&0xffffffff), (int32_t)(x&0xffffffff));
//}
static void tsf_voice_render_fast(tsf* f, struct tsf_voice* v, short* outputBuffer, int numSamples) {
    struct tsf_region* region = v->region;
    short* outL = outputBuffer;
    short* outR = (f->outputmode == TSF_STEREO_UNWEAVED ? outL + numSamples : TSF_NULL);

    // Cache some values, to give them at least some chance of ending up in registers.
    TSF_BOOL updateModEnv = (region->modEnvToPitch || region->modEnvToFilterFc);
    TSF_BOOL updateModLFO = (v->modlfo.delta && (region->modLfoToPitch || region->modLfoToFilterFc || region->modLfoToVolume));
    TSF_BOOL updateVibLFO = (v->viblfo.delta && (region->vibLfoToPitch));
    TSF_BOOL isLooping    = (v->loopSizeF32P32 > 0);
    fixed32p32 tmpSampleEndF32P32 = (fixed32p32)(region->end) << 32;
    fixed32p32 tmpSourceSamplePositionF32P32 = v->sourceSamplePositionF32P32;

    TSF_BOOL dynamicPitchRatio = (region->modLfoToPitch || region->modEnvToPitch || region->vibLfoToPitch);
    fixed32p32 pitchRatioF32P32, tmpPitchRatioF32P32;
    float tmpModLfoToPitch, tmpVibLfoToPitch, tmpModEnvToPitch;

    TSF_BOOL dynamicGain = (region->modLfoToVolume != 0);
    float noteGain, tmpNoteGain, tmpModLfoToVolume;

    if (dynamicPitchRatio) {
        tmpPitchRatioF32P32 = v->pitchRatioF32P32, pitchRatioF32P32 = 0, tmpModLfoToPitch = (float)region->modLfoToPitch, tmpVibLfoToPitch = (float)region->vibLfoToPitch, tmpModEnvToPitch = (float)region->modEnvToPitch;
    } else {
        pitchRatioF32P32 = v->pitchRatioF32P32, tmpModLfoToPitch = 0, tmpVibLfoToPitch = 0, tmpModEnvToPitch = 0;
    }

    if (dynamicGain) {
        noteGain = 0, tmpNoteGain = v->noteGain, tmpModLfoToVolume = (float)region->modLfoToVolume * 0.1f;
    } else {
        noteGain = v->noteGain, tmpModLfoToVolume = 0;
    }

    while (numSamples) {
        float gainMono;
        int blockSamples = (numSamples > TSF_RENDER_EFFECTSAMPLEBLOCK ? TSF_RENDER_EFFECTSAMPLEBLOCK : numSamples);
        numSamples -= blockSamples;

        if (dynamicPitchRatio) {
            if (v->modlfo.level || v->viblfo.level || v->modenv.level) {
                pitchRatioF32P32 = tmpPitchRatioF32P32 * tsf_timecents2Secsd(v->modlfo.level * tmpModLfoToPitch + v->viblfo.level * tmpVibLfoToPitch + v->modenv.level * tmpModEnvToPitch);
            } else {
                pitchRatioF32P32 = tmpPitchRatioF32P32;    // If all levels are 0, just bypass conversion function
            }
        }

        if (dynamicGain) {
            if (v->modlfo.level) {
                noteGain = tmpNoteGain * tsf_decibelsToGain(v->modlfo.level * tmpModLfoToVolume);
            } else {
                noteGain = tmpNoteGain;    // If level is 0, just bypass conversion function
            }
        }

        gainMono = noteGain * v->ampenv.level;
        short gainMonoFP = gainMono * 32767;

        // Update EG.
        tsf_voice_envelope_process(&v->ampenv, blockSamples, f->outSampleRate);
        if (updateModEnv) {
            tsf_voice_envelope_process(&v->modenv, blockSamples, f->outSampleRate);
        }

        // Update LFOs.
        if (updateModLFO) {
            tsf_voice_lfo_process(&v->modlfo, blockSamples);
        }
        if (updateVibLFO) {
            tsf_voice_lfo_process(&v->viblfo, blockSamples);
        }

        while (blockSamples--) {
            unsigned int pos = (unsigned int)(tmpSourceSamplePositionF32P32 >> 32);
            if (pos == 0xffffffff) {
                pos = 0;
            }
            short val = tsf_read_short_cached(f, pos);
            int32_t val32 = (int)val * (int)gainMonoFP;

            *outL++ += val32 >> 16;
            if (f->outputmode != TSF_MONO) {
                *outR++ += val32 >> 16;
            }

            // Next sample.
            tmpSourceSamplePositionF32P32 += pitchRatioF32P32;

            if (tmpSourceSamplePositionF32P32 >= v->loopEndF32P32) {
                if (isLooping) {
                    tmpSourceSamplePositionF32P32 -= v->loopSizeF32P32;
                } else if (tmpSourceSamplePositionF32P32 >= tmpSampleEndF32P32) {
                    break;
                }
            }
        }

        if (tmpSourceSamplePositionF32P32 >= tmpSampleEndF32P32 || v->ampenv.segment == TSF_SEGMENT_DONE) {
            tsf_voice_kill(v);
            return;
        }
    }

    v->sourceSamplePositionF32P32 = tmpSourceSamplePositionF32P32;
}




TSFDEF tsf* tsf_load(struct tsf_stream* stream) {
    tsf* res = TSF_NULL;
    struct tsf_riffchunk chunkHead;
    struct tsf_riffchunk chunkList;
    struct tsf_hydra hydra;
    int fontSamplesOffset = 0;
    unsigned int fontSampleCount = 0;

    if (!tsf_riffchunk_read(TSF_NULL, &chunkHead, stream) || !TSF_FourCCEquals(chunkHead.id, "sfbk")) {
        //if (e) *e = TSF_INVALID_NOSF2HEADER;
        return res;
    }

    // Read hydra and locate sample data.
    TSF_MEMSET(&hydra, 0, sizeof(hydra));
    hydra.stream = stream;
    while (tsf_riffchunk_read(&chunkHead, &chunkList, stream)) {
        struct tsf_riffchunk chunk;
        if (TSF_FourCCEquals(chunkList.id, "pdta")) {
            while (tsf_riffchunk_read(&chunkList, &chunk, stream)) {
#define GetChunkOffset(chunkName) (TSF_FourCCEquals(chunk.id, #chunkName) && !(chunk.size % chunkName##SizeInFile)) \
					{ \
						int num = chunk.size / chunkName##SizeInFile; \
						hydra.chunkName##Num = num; \
						hydra.chunkName##Offset = stream->tell(stream->data); \
						stream->skip(stream->data, num * chunkName##SizeInFile); \
					}
                if      GetChunkOffset(phdr)
                    else if GetChunkOffset(pbag)
                        else if GetChunkOffset(pmod)
                            else if GetChunkOffset(pgen)
                                else if GetChunkOffset(inst)
                                    else if GetChunkOffset(ibag)
                                        else if GetChunkOffset(imod)
                                            else if GetChunkOffset(igen)
                                                else if GetChunkOffset(shdr)
                                                    else {
                                                        stream->skip(stream->data, chunk.size);
                                                    }
#undef HandleChunk
            }
        } else if (TSF_FourCCEquals(chunkList.id, "sdta")) {
            while (tsf_riffchunk_read(&chunkList, &chunk, stream)) {
                if (TSF_FourCCEquals(chunk.id, "smpl")) {
                    tsf_load_samples(&fontSamplesOffset, &fontSampleCount, &chunk, stream);
                } else {
                    stream->skip(stream->data, chunk.size);
                }
            }
        } else {
            stream->skip(stream->data, chunkList.size);
        }
    }
    if (!hydra.phdrNum || !hydra.pbagNum || !hydra.pmodNum || !hydra.pgenNum || !hydra.instNum || !hydra.ibagNum || !hydra.imodNum || !hydra.igenNum || !hydra.shdrNum) {
        //if (e) *e = TSF_INVALID_INCOMPLETE;
    } else if (fontSamplesOffset == 0) {
        //if (e) *e = TSF_INVALID_NOSAMPLEDATA;
    } else {
        res = (tsf*)TSF_MALLOC(sizeof(tsf));
        TSF_MEMSET(res, 0, sizeof(tsf));
        res->presetNum = hydra.phdrNum - 1;
        res->presets = (struct tsf_preset*)TSF_MALLOC(res->presetNum * sizeof(struct tsf_preset));
        TSF_MEMSET(res->presets, 0, res->presetNum * sizeof(struct tsf_preset));
        res->fontSamplesOffset = fontSamplesOffset;
        res->fontSampleCount = fontSampleCount;
        res->outSampleRate = 44100.0f;
        res->hydra = (struct tsf_hydra*)TSF_MALLOC(sizeof(struct tsf_hydra));
        TSF_MEMCPY(res->hydra, &hydra, sizeof(*res->hydra));
        res->hydra->stream = (struct tsf_stream*)TSF_MALLOC(sizeof(struct tsf_stream));
        TSF_MEMCPY(res->hydra->stream, stream, sizeof(*res->hydra->stream));

        // Cached sample
        for (int i = 0; i < TSF_BUFFS; i++) {
            res->buffer[i] = (short*)TSF_MALLOC(TSF_BUFFSIZE * sizeof(short));
            res->offset[i] = 0xfffffff;
            res->timestamp[i] = -1;
        }
        res->epoch = 0;
    }
    return res;
}

TSFDEF void tsf_close(tsf* f) {
    struct tsf_preset *preset, *presetEnd;
    if (!f) {
        return;
    }
    for (preset = f->presets, presetEnd = preset + f->presetNum; preset != presetEnd; preset++) {
        TSF_FREE(preset->regions);
    }
    TSF_FREE(f->presets);
    TSF_FREE(f->voices);
    if (f->channels) {
        TSF_FREE(f->channels->channels);
        TSF_FREE(f->channels);
    }
    TSF_FREE(f->outputSamples);
    f->hydra->stream->close(f->hydra->stream->data);
    TSF_FREE(f->hydra->stream);
    TSF_FREE(f->hydra);
    for (int i = 0; i < TSF_BUFFS; i++) {
        TSF_FREE(f->buffer[i]);
    }
    TSF_FREE(f);
}

TSFDEF void tsf_reset(tsf* f) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    for (; v != vEnd; v++)
        if (v->playingPreset != -1 && (v->ampenv.segment < TSF_SEGMENT_RELEASE || v->ampenv.parameters.release)) {
            tsf_voice_endquick(v, f->outSampleRate);
        }
    if (f->channels) {
        TSF_FREE(f->channels->channels);
        TSF_FREE(f->channels);
        f->channels = TSF_NULL;
    }
}

TSFDEF int tsf_get_presetindex(const tsf* f, int bank, int preset_number) {
    const struct tsf_preset *presets;
    int i, iMax;
    for (presets = f->presets, i = 0, iMax = f->presetNum; i < iMax; i++)
        if (presets[i].preset == preset_number && presets[i].bank == bank) {
            return i;
        }
    return -1;
}

TSFDEF int tsf_get_presetcount(const tsf* f) {
    return f->presetNum;
}

TSFDEF const char* tsf_get_presetname(const tsf* f, int preset) {
    if (preset >= 0 && preset < f->presetNum && f->presets[preset].regions == NULL) {
        tsf_load_preset(f, f->hydra, preset);
    }
    return (preset < 0 || preset >= f->presetNum ? TSF_NULL : f->presets[preset].presetName);
}

TSFDEF const char* tsf_bank_get_presetname(const tsf* f, int bank, int preset_number) {
    return tsf_get_presetname(f, tsf_get_presetindex(f, bank, preset_number));
}

TSFDEF void tsf_set_output(tsf* f, enum TSFOutputMode outputmode, int samplerate, float global_gain_db) {
    f->outputmode = outputmode;
    f->outSampleRate = (float)(samplerate >= 1 ? samplerate : 44100.0f);
    f->globalGainDB = global_gain_db;
}

TSFDEF void tsf_note_on(tsf* f, int preset_index, int key, float vel) {
    short midiVelocity = (short)(vel * 127);
    int voicePlayIndex;
    struct tsf_region *region, *regionEnd;

    if (preset_index < 0 || preset_index >= f->presetNum) {
        return;
    }
    if (vel <= 0.0f) {
        tsf_note_off(f, preset_index, key);
        return;
    }
    if (f->presets[preset_index].regions == NULL) {
        tsf_load_preset(f, f->hydra, preset_index);
    }

    // Play all matching regions.
    voicePlayIndex = f->voicePlayIndex++;
    for (region = f->presets[preset_index].regions, regionEnd = region + f->presets[preset_index].regionNum; region != regionEnd; region++) {
        struct tsf_voice *voice, *v, *vEnd; TSF_BOOL doLoop; float lowpassFilterQDB, lowpassFc;
        if (key < region->lokey || key > region->hikey || midiVelocity < region->lovel || midiVelocity > region->hivel) {
            continue;
        }

        voice = TSF_NULL, v = f->voices, vEnd = v + f->voiceNum;
        if (region->group) {
            for (; v != vEnd; v++)
                if (v->playingPreset == preset_index && v->region->group == region->group) {
                    tsf_voice_endquick(v, f->outSampleRate);
                } else if (v->playingPreset == -1 && !voice) {
                    voice = v;
                }
        } else for (; v != vEnd; v++) if (v->playingPreset == -1) {
                    voice = v;
                    break;
                }

        if (!voice) {
            f->voiceNum += 4;
            struct tsf_voice *saveVoice = f->voices;
            f->voices = (struct tsf_voice*)TSF_REALLOC(f->voices, f->voiceNum * sizeof(struct tsf_voice));
            if (!f->voices) {
                f->voices = saveVoice;
                printf("OOM, no room for new voice.  Ignoring note_on\n");
                return;
            }
            voice = &f->voices[f->voiceNum - 4];
            voice[1].playingPreset = voice[2].playingPreset = voice[3].playingPreset = -1;
            voice[1].playIndex = voice[2].playIndex = voice[3].playIndex = -1;
        }

        voice->region = region;
        voice->playingPreset = preset_index;
        voice->playingKey = key;
        voice->playIndex = voicePlayIndex;
        voice->noteGain = vel * tsf_decibelsToGain(f->globalGainDB - region->attenuation);

        if (f->channels) {
            f->channels->setupVoice(f, voice);
        } else {
            tsf_voice_calcpitchratio(voice, 0, f->outSampleRate);
            // The SFZ spec is silent about the pan curve, but a 3dB pan law seems common. This sqrt() curve matches what Dimension LE does; Alchemy Free seems closer to sin(adjustedPan * pi/2).
            voice->panFactorLeft  = TSF_SQRTF(0.5f - region->pan);
            voice->panFactorRight = TSF_SQRTF(0.5f + region->pan);
        }

        // Offset/end.
        voice->sourceSamplePosition = region->offset;

        // Loop.
        doLoop = (region->loop_mode != TSF_LOOPMODE_NONE && region->loop_start < region->loop_end);
        voice->loopStart = (doLoop ? region->loop_start : 0);
        voice->loopEnd = (doLoop ? region->loop_end : 0);

        // Setup envelopes.
        tsf_voice_envelope_setup(&voice->ampenv, &region->ampenv, key, midiVelocity, TSF_TRUE, f->outSampleRate);
        tsf_voice_envelope_setup(&voice->modenv, &region->modenv, key, midiVelocity, TSF_FALSE, f->outSampleRate);

        // Setup lowpass filter.
        lowpassFc = (region->initialFilterFc <= 13500 ? tsf_cents2Hertz((float)region->initialFilterFc) / f->outSampleRate : 1.0f);
        lowpassFilterQDB = region->initialFilterQ / 10.0f;
        voice->lowpass.QInv = 1.0 / TSF_POW(10.0, (lowpassFilterQDB / 20.0));
        voice->lowpass.z1 = voice->lowpass.z2 = 0;
        voice->lowpass.active = (lowpassFc < 0.499f);
        if (voice->lowpass.active) {
            tsf_voice_lowpass_setup(&voice->lowpass, lowpassFc);
        }

        // Setup LFO filters.
        tsf_voice_lfo_setup(&voice->modlfo, region->delayModLFO, region->freqModLFO, f->outSampleRate);
        tsf_voice_lfo_setup(&voice->viblfo, region->delayVibLFO, region->freqVibLFO, f->outSampleRate);
    }
}

/**
    Returns the generated playing index that can be used to identify all voices related to this note.
*/
TSFDEF int tsf_note_on_fast(tsf* f, int preset_index, int key, float vel) {
    if (preset_index < 0 || preset_index >= f->presetNum) {
        return -1;
    }
    if (!vel) {
        tsf_note_off(f, preset_index, key);
        return -1;
    }
    if (f->presets[preset_index].regions == NULL) {
        tsf_load_preset(f, f->hydra, preset_index);
    }

    short midiVelocity = (short)(vel * 127);
    struct tsf_region *region, *regionEnd;

    // Play all matching regions.
    int voicePlayIndex = f->voicePlayIndex++;
    for (region = f->presets[preset_index].regions, regionEnd = region + f->presets[preset_index].regionNum; region != regionEnd; region++) {
        if (key < region->lokey || key > region->hikey || midiVelocity < region->lovel || midiVelocity > region->hivel) {
            continue;
        }

        struct tsf_voice *voice, *v, *vEnd; TSF_BOOL doLoop;
        voice = TSF_NULL, v = f->voices, vEnd = v + f->voiceNum;
        if (region->group) {
            for (; v != vEnd; v++)
                if (v->playingPreset == preset_index && v->region->group == region->group) {
                    tsf_voice_endquick(v, f->outSampleRate);
                } else if (v->playingPreset == -1 && !voice) {
                    voice = v;
                }
        } else for (; v != vEnd; v++) if (v->playingPreset == -1) {
                    voice = v;
                    break;
                }

        if (!voice) {
            f->voiceNum += 4;
            struct tsf_voice *saveVoice = f->voices;
            f->voices = (struct tsf_voice*)TSF_REALLOC(f->voices, f->voiceNum * sizeof(struct tsf_voice));
            if (!f->voices) {
                f->voices = saveVoice;
                printf("OOM, no room for new voice.  Ignoring note_on\n");
                return -1;
            }
            voice = &f->voices[f->voiceNum - 4];
            voice[1].playingPreset = voice[2].playingPreset = voice[3].playingPreset = -1;
            voice[1].playIndex = voice[2].playIndex = voice[3].playIndex = -1;
        }

        voice->region = region;
        voice->playingPreset = preset_index;
        voice->playingKey = key;
        voice->playIndex = voicePlayIndex;
        voice->noteGain = vel * tsf_decibelsToGain(f->globalGainDB - region->attenuation);

        if (f->channels) {
            f->channels->setupVoice(f, voice);
        } else {
            tsf_voice_calcpitchratio(voice, 0, f->outSampleRate);
            voice->pitchRatioF32P32 = voice->pitchRatio * (1LL << 32);
        }

        // Offset/end.
        voice->sourceSamplePositionF32P32 = ((int64_t)region->offset) << 32;

        // Loop.
        doLoop = (region->loop_mode != TSF_LOOPMODE_NONE && region->loop_start < region->loop_end);
        voice->loopStartF32P32 = doLoop ? ((int64_t)region->loop_start + 1) << 32 : 0;
        voice->loopEndF32P32 = doLoop ? ((int64_t)region->loop_end + 1) << 32 : 0;
        voice->loopSizeF32P32 = doLoop ? voice->loopEndF32P32 - voice->loopStartF32P32 + (1LL << 32) : 0;

        // Setup envelopes.
        tsf_voice_envelope_setup(&voice->ampenv, &region->ampenv, key, midiVelocity, TSF_TRUE, f->outSampleRate);
        tsf_voice_envelope_setup(&voice->modenv, &region->modenv, key, midiVelocity, TSF_FALSE, f->outSampleRate);

        // Setup LFO filters.
        tsf_voice_lfo_setup(&voice->modlfo, region->delayModLFO, region->freqModLFO, f->outSampleRate);
        tsf_voice_lfo_setup(&voice->viblfo, region->delayVibLFO, region->freqVibLFO, f->outSampleRate);
    }

    return voicePlayIndex;
}

TSFDEF int tsf_bank_note_on(tsf* f, int bank, int preset_number, int key, float vel) {
    int preset_index = tsf_get_presetindex(f, bank, preset_number);
    if (preset_index == -1) {
        return 0;
    }
    tsf_note_on(f, preset_index, key, vel);
    return 1;
}

TSFDEF void tsf_note_off(tsf* f, int preset_index, int key) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum, *vMatchFirst = TSF_NULL, *vMatchLast = TSF_NULL;
    for (; v != vEnd; v++) {
        //Find the first and last entry in the voices list with matching preset, key and look up the smallest play index
        if (v->playingPreset != preset_index || v->playingKey != key || v->ampenv.segment >= TSF_SEGMENT_RELEASE) {
            continue;
        } else if (!vMatchFirst || v->playIndex < vMatchFirst->playIndex) {
            vMatchFirst = vMatchLast = v;
        } else if (v->playIndex == vMatchFirst->playIndex) {
            vMatchLast = v;
        }
    }
    if (!vMatchFirst) {
        return;
    }
    for (v = vMatchFirst; v <= vMatchLast; v++) {
        //Stop all voices with matching preset, key and the smallest play index which was enumerated above
        if (v != vMatchFirst && v != vMatchLast &&
                (v->playIndex != vMatchFirst->playIndex || v->playingPreset != preset_index || v->playingKey != key || v->ampenv.segment >= TSF_SEGMENT_RELEASE)) {
            continue;
        }
        tsf_voice_end(v, f->outSampleRate);
    }
}

/**
    Stops all voices with the given playing index. If no key provided or if -1, fallbacks to tsf_note_off
*/
TSFDEF void tsf_note_off_fast(tsf* f, int preset_index, int key, int playIndex = -1) {
    if (playIndex < 0) {
        tsf_note_off(f, preset_index, key);
    } else
        for (struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum; v != vEnd; v++)
            if (v->playIndex == playIndex && v->playingPreset == preset_index && v->playingKey == key && v->ampenv.segment < TSF_SEGMENT_RELEASE) {
                tsf_voice_end(v, f->outSampleRate);
            }
}

TSFDEF int tsf_bank_note_off(tsf* f, int bank, int preset_number, int key) {
    int preset_index = tsf_get_presetindex(f, bank, preset_number);
    if (preset_index == -1) {
        return 0;
    }
    tsf_note_off(f, preset_index, key);
    return 1;
}

TSFDEF void tsf_note_off_all(tsf* f) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    for (; v != vEnd; v++) if (v->playingPreset != -1 && v->ampenv.segment < TSF_SEGMENT_RELEASE) {
            tsf_voice_end(v, f->outSampleRate);
        }
}

TSFDEF int tsf_active_voice_count(tsf* f) {
    int count = 0;
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    for (; v != vEnd; v++) if (v->playingPreset != -1) {
            count++;
        }
    return count;
}

TSFDEF void tsf_render_short(tsf* f, short* buffer, int samples, int flag_mixing) {
    float *floatSamples;
    int channelSamples = (f->outputmode == TSF_MONO ? 1 : 2) * samples, floatBufferSize = channelSamples * sizeof(float);
    short* bufferEnd = buffer + channelSamples;
    if (floatBufferSize > f->outputSampleSize) {
        TSF_FREE(f->outputSamples);
        f->outputSamples = (float*)TSF_MALLOC(floatBufferSize);
        f->outputSampleSize = floatBufferSize;
    }

    tsf_render_float(f, f->outputSamples, samples, TSF_FALSE);

    floatSamples = f->outputSamples;
    if (flag_mixing)
        while (buffer != bufferEnd) {
            float v = *floatSamples++;
            int vi = *buffer + (v < -1.00004566f ? (int) -32768 : (v > 1.00001514f ? (int)32767 : (int)(v * 32767.5f)));
            *buffer++ = (vi < -32768 ? (short) -32768 : (vi > 32767 ? (short)32767 : (short)vi));
        } else
        while (buffer != bufferEnd) {
            float v = *floatSamples++;
            *buffer++ = (v < -1.00004566f ? (short) -32768 : (v > 1.00001514f ? (short)32767 : (short)(v * 32767.5f)));
        }
}

TSFDEF void tsf_render_float(tsf* f, float* buffer, int samples, int flag_mixing) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    if (!flag_mixing) {
        TSF_MEMSET(buffer, 0, (f->outputmode == TSF_MONO ? 1 : 2) * sizeof(float) * samples);
    }
    for (; v != vEnd; v++)
        if (v->playingPreset != -1) {
            tsf_voice_render(f, v, buffer, samples);
        }
}

TSFDEF void tsf_render_short_fast(tsf* f, short* buffer, int samples, int flag_mixing) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    if (!flag_mixing) {
        TSF_MEMSET(buffer, 0, (f->outputmode == TSF_MONO ? 1 : 2) * sizeof(short) * samples);
    }
    for (; v != vEnd; v++) {
        if (v->playingPreset != -1) {
            tsf_voice_render_fast(f, v, buffer, samples);
        }
        yield();
    }
}


static void tsf_channel_setup_voice(tsf* f, struct tsf_voice* v) {
    struct tsf_channel* c = &f->channels->channels[f->channels->activeChannel];
    float newpan = v->region->pan + c->panOffset;
    v->playingChannel = f->channels->activeChannel;
    v->noteGain *= tsf_decibelsToGain(c->gainDB);
    tsf_voice_calcpitchratio(v, (c->pitchWheel == 8192 ? c->tuning : ((c->pitchWheel / 16383.0f * c->pitchRange * 2.0f) - c->pitchRange + c->tuning)), f->outSampleRate);
    if (newpan <= -0.5f) {
        v->panFactorLeft = 1.0f;
        v->panFactorRight = 0.0f;
    } else if (newpan >=  0.5f) {
        v->panFactorLeft = 0.0f;
        v->panFactorRight = 1.0f;
    } else {
        v->panFactorLeft = TSF_SQRTF(0.5f - newpan);
        v->panFactorRight = TSF_SQRTF(0.5f + newpan);
    }
}

static struct tsf_channel* tsf_channel_init(tsf* f, int channel) {
    int i;
    if (f->channels && channel < f->channels->channelNum) {
        return &f->channels->channels[channel];
    }
    if (!f->channels) {
        f->channels = (struct tsf_channels*)TSF_MALLOC(sizeof(struct tsf_channels));
        f->channels->setupVoice = &tsf_channel_setup_voice;
        f->channels->channels = NULL;
        f->channels->channelNum = 0;
        f->channels->activeChannel = 0;
    }
    i = f->channels->channelNum;
    f->channels->channelNum = channel + 1;
    f->channels->channels = (struct tsf_channel*)TSF_REALLOC(f->channels->channels, f->channels->channelNum * sizeof(struct tsf_channel));
    for (; i <= channel; i++) {
        struct tsf_channel* c = &f->channels->channels[i];
        c->presetIndex = c->bank = 0;
        c->pitchWheel = c->midiPan = 8192;
        c->midiVolume = c->midiExpression = 16383;
        c->midiRPN = 0xFFFF;
        c->midiData = 0;
        c->panOffset = 0.0f;
        c->gainDB = 0.0f;
        c->pitchRange = 2.0f;
        c->tuning = 0.0f;
    }
    return &f->channels->channels[channel];
}

static void tsf_channel_applypitch(tsf* f, int channel, struct tsf_channel* c) {
    struct tsf_voice *v, *vEnd;
    float pitchShift = (c->pitchWheel == 8192 ? c->tuning : ((c->pitchWheel / 16383.0f * c->pitchRange * 2.0f) - c->pitchRange + c->tuning));
    for (v = f->voices, vEnd = v + f->voiceNum; v != vEnd; v++)
        if (v->playingChannel == channel && v->playingPreset != -1) {
            tsf_voice_calcpitchratio(v, pitchShift, f->outSampleRate);
        }
}

TSFDEF void tsf_channel_set_presetindex(tsf* f, int channel, int preset_index) {
    tsf_channel_init(f, channel)->presetIndex = (unsigned short)preset_index;
}

TSFDEF int tsf_channel_set_presetnumber(tsf* f, int channel, int preset_number, int flag_mididrums) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    int preset_index;
    if (flag_mididrums) {
        preset_index = tsf_get_presetindex(f, 128 | (c->bank & 0x7FFF), preset_number);
        if (preset_index == -1) {
            preset_index = tsf_get_presetindex(f, 128, preset_number);
        }
        if (preset_index == -1) {
            preset_index = tsf_get_presetindex(f, 128, 0);
        }
        if (preset_index == -1) {
            preset_index = tsf_get_presetindex(f, (c->bank & 0x7FFF), preset_number);
        }
    } else {
        preset_index = tsf_get_presetindex(f, (c->bank & 0x7FFF), preset_number);
    }
    if (preset_index == -1) {
        preset_index = tsf_get_presetindex(f, 0, preset_number);
    }
    if (preset_index != -1) {
        c->presetIndex = (unsigned short)preset_index;
        return 1;
    }
    return 0;
}

TSFDEF void tsf_channel_set_bank(tsf* f, int channel, int bank) {
    tsf_channel_init(f, channel)->bank = (unsigned short)bank;
}

TSFDEF int tsf_channel_set_bank_preset(tsf* f, int channel, int bank, int preset_number) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    int preset_index = tsf_get_presetindex(f, bank, preset_number);
    if (preset_index == -1) {
        return 0;
    }
    c->presetIndex = (unsigned short)preset_index;
    c->bank = (unsigned short)bank;
    return 1;
}

TSFDEF void tsf_channel_set_pan(tsf* f, int channel, float pan) {
    struct tsf_voice *v, *vEnd;
    for (v = f->voices, vEnd = v + f->voiceNum; v != vEnd; v++)
        if (v->playingChannel == channel && v->playingPreset != -1) {
            float newpan = v->region->pan + pan - 0.5f;
            if (newpan <= -0.5f) {
                v->panFactorLeft = 1.0f;
                v->panFactorRight = 0.0f;
            } else if (newpan >=  0.5f) {
                v->panFactorLeft = 0.0f;
                v->panFactorRight = 1.0f;
            } else {
                v->panFactorLeft = TSF_SQRTF(0.5f - newpan);
                v->panFactorRight = TSF_SQRTF(0.5f + newpan);
            }
        }
    tsf_channel_init(f, channel)->panOffset = pan - 0.5f;
}

TSFDEF void tsf_channel_set_volume(tsf* f, int channel, float volume) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    float gainDB = tsf_gainToDecibels(volume), gainDBChange = gainDB - c->gainDB;
    struct tsf_voice *v, *vEnd;
    if (gainDBChange == 0) {
        return;
    }
    for (v = f->voices, vEnd = v + f->voiceNum; v != vEnd; v++)
        if (v->playingChannel == channel && v->playingPreset != -1) {
            v->noteGain *= tsf_decibelsToGain(gainDBChange);
        }
    c->gainDB = gainDB;
}

TSFDEF void tsf_channel_set_pitchwheel(tsf* f, int channel, int pitch_wheel) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    if (c->pitchWheel == pitch_wheel) {
        return;
    }
    c->pitchWheel = (unsigned short)pitch_wheel;
    tsf_channel_applypitch(f, channel, c);
}

TSFDEF void tsf_channel_set_pitchrange(tsf* f, int channel, float pitch_range) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    if (c->pitchRange == pitch_range) {
        return;
    }
    c->pitchRange = pitch_range;
    if (c->pitchWheel != 8192) {
        tsf_channel_applypitch(f, channel, c);
    }
}

TSFDEF void tsf_channel_set_tuning(tsf* f, int channel, float tuning) {
    struct tsf_channel *c = tsf_channel_init(f, channel);
    if (c->tuning == tuning) {
        return;
    }
    c->tuning = tuning;
    tsf_channel_applypitch(f, channel, c);
}

TSFDEF void tsf_channel_note_on(tsf* f, int channel, int key, float vel) {
    if (!f->channels || channel >= f->channels->channelNum) {
        return;
    }
    f->channels->activeChannel = channel;
    tsf_note_on(f, f->channels->channels[channel].presetIndex, key, vel);
}

TSFDEF void tsf_channel_note_off(tsf* f, int channel, int key) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum, *vMatchFirst = TSF_NULL, *vMatchLast = TSF_NULL;
    for (; v != vEnd; v++) {
        //Find the first and last entry in the voices list with matching channel, key and look up the smallest play index
        if (v->playingPreset == -1 || v->playingChannel != channel || v->playingKey != key || v->ampenv.segment >= TSF_SEGMENT_RELEASE) {
            continue;
        } else if (!vMatchFirst || v->playIndex < vMatchFirst->playIndex) {
            vMatchFirst = vMatchLast = v;
        } else if (v->playIndex == vMatchFirst->playIndex) {
            vMatchLast = v;
        }
    }
    if (!vMatchFirst) {
        return;
    }
    for (v = vMatchFirst; v <= vMatchLast; v++) {
        //Stop all voices with matching channel, key and the smallest play index which was enumerated above
        if (v != vMatchFirst && v != vMatchLast &&
                (v->playIndex != vMatchFirst->playIndex || v->playingPreset == -1 || v->playingChannel != channel || v->playingKey != key || v->ampenv.segment >= TSF_SEGMENT_RELEASE)) {
            continue;
        }
        tsf_voice_end(v, f->outSampleRate);
    }
}

TSFDEF void tsf_channel_note_off_all(tsf* f, int channel) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    for (; v != vEnd; v++)
        if (v->playingPreset != -1 && v->playingChannel == channel && v->ampenv.segment < TSF_SEGMENT_RELEASE) {
            tsf_voice_end(v, f->outSampleRate);
        }
}

TSFDEF void tsf_channel_sounds_off_all(tsf* f, int channel) {
    struct tsf_voice *v = f->voices, *vEnd = v + f->voiceNum;
    for (; v != vEnd; v++)
        if (v->playingPreset != -1 && v->playingChannel == channel && (v->ampenv.segment < TSF_SEGMENT_RELEASE || v->ampenv.parameters.release)) {
            tsf_voice_endquick(v, f->outSampleRate);
        }
}

TSFDEF void tsf_channel_midi_control(tsf* f, int channel, int controller, int control_value) {
    struct tsf_channel* c = tsf_channel_init(f, channel);
    switch (controller) {
    case   7 /*VOLUME_MSB*/      : c->midiVolume     = (unsigned short)((c->midiVolume     & 0x7F) | (control_value << 7)); goto TCMC_SET_VOLUME;
    case  39 /*VOLUME_LSB*/      : c->midiVolume     = (unsigned short)((c->midiVolume     & 0x3F80) |  control_value);       goto TCMC_SET_VOLUME;
    case  11 /*EXPRESSION_MSB*/  : c->midiExpression = (unsigned short)((c->midiExpression & 0x7F) | (control_value << 7)); goto TCMC_SET_VOLUME;
    case  43 /*EXPRESSION_LSB*/  : c->midiExpression = (unsigned short)((c->midiExpression & 0x3F80) |  control_value);       goto TCMC_SET_VOLUME;
    case  10 /*PAN_MSB*/         : c->midiPan        = (unsigned short)((c->midiPan        & 0x7F) | (control_value << 7)); goto TCMC_SET_PAN;
    case  42 /*PAN_LSB*/         : c->midiPan        = (unsigned short)((c->midiPan        & 0x3F80) |  control_value);       goto TCMC_SET_PAN;
    case   6 /*DATA_ENTRY_MSB*/  : c->midiData       = (unsigned short)((c->midiData       & 0x7F)   | (control_value << 7)); goto TCMC_SET_DATA;
    case  38 /*DATA_ENTRY_LSB*/  : c->midiData       = (unsigned short)((c->midiData       & 0x3F80) |  control_value);       goto TCMC_SET_DATA;
    case   0 /*BANK_SELECT_MSB*/ : c->bank = (unsigned short)(0x8000 | control_value); return; //bank select MSB alone acts like LSB
    case  32 /*BANK_SELECT_LSB*/ : c->bank = (unsigned short)((c->bank & 0x8000 ? ((c->bank & 0x7F) << 7) : 0) | control_value); return;
    case 101 /*RPN_MSB*/         : c->midiRPN = (unsigned short)(((c->midiRPN == 0xFFFF ? 0 : c->midiRPN) & 0x7F) | (control_value << 7)); return;
    case 100 /*RPN_LSB*/         : c->midiRPN = (unsigned short)(((c->midiRPN == 0xFFFF ? 0 : c->midiRPN) & 0x3F80) |  control_value); return;
    case  98 /*NRPN_LSB*/        : c->midiRPN = 0xFFFF; return;
    case  99 /*NRPN_MSB*/        : c->midiRPN = 0xFFFF; return;
    case 120 /*ALL_SOUND_OFF*/   : tsf_channel_sounds_off_all(f, channel); return;
    case 123 /*ALL_NOTES_OFF*/   : tsf_channel_note_off_all(f, channel);   return;
    case 121 /*ALL_CTRL_OFF*/    :
        c->midiVolume = c->midiExpression = 16383;
        c->midiPan = 8192;
        c->bank = 0;
        tsf_channel_set_volume(f, channel, 1.0f);
        tsf_channel_set_pan(f, channel, 0.5f);
        tsf_channel_set_pitchrange(f, channel, 2.0f);
        return;
    }
    return;
TCMC_SET_VOLUME:
    //Raising to the power of 3 seems to result in a decent sounding volume curve for MIDI
    tsf_channel_set_volume(f, channel, TSF_POWF((c->midiVolume / 16383.0f) * (c->midiExpression / 16383.0f), 3.0f));
    return;
TCMC_SET_PAN:
    tsf_channel_set_pan(f, channel, c->midiPan / 16383.0f);
    return;
TCMC_SET_DATA:
    if (c->midiRPN == 0) {
        tsf_channel_set_pitchrange(f, channel, (c->midiData >> 7) + 0.01f * (c->midiData & 0x7F));
    } else if (c->midiRPN == 1) {
        tsf_channel_set_tuning(f, channel, (int)c->tuning + ((float)c->midiData - 8192.0f) / 8192.0f);    //fine tune
    } else if (c->midiRPN == 2 && controller == 6) {
        tsf_channel_set_tuning(f, channel, ((float)control_value - 64.0f) + (c->tuning - (int)c->tuning));    //coarse tune
    }
    return;
}

TSFDEF int tsf_channel_get_preset_index(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->channels->channels[channel].presetIndex : 0);
}

TSFDEF int tsf_channel_get_preset_bank(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? (f->channels->channels[channel].bank & 0x7FFF) : 0);
}

TSFDEF int tsf_channel_get_preset_number(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->presets[f->channels->channels[channel].presetIndex].preset : 0);
}

TSFDEF float tsf_channel_get_pan(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->channels->channels[channel].panOffset - 0.5f : 0.5f);
}

TSFDEF float tsf_channel_get_volume(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? tsf_decibelsToGain(f->channels->channels[channel].gainDB) : 1.0f);
}

TSFDEF int tsf_channel_get_pitchwheel(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->channels->channels[channel].pitchWheel : 8192);
}

TSFDEF float tsf_channel_get_pitchrange(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->channels->channels[channel].pitchRange : 2.0f);
}

TSFDEF float tsf_channel_get_tuning(tsf* f, int channel) {
    return (f->channels && channel < f->channels->channelNum ? f->channels->channels[channel].tuning : 0.0f);
}

#ifdef __cplusplus
}
#endif

#endif //TSF_IMPLEMENTATION

#endif // ! ESP32
