path: root/src/mdaPiano.cpp

/* ==================================================
 * LV2 port of the famous mda Piano VSTi
 * ==================================================
 *
 * Port
 *   Author:    Ricardo Wurmus (rekado)
 *   Based on:  mda-vst-src-2010-02-14.zip
 *
 * mda Piano v1.0
 *   Copyright(c)1999-2000 Paul Kellett (maxim digital audio)
 *   Based on VST2 SDK (c)1996-1999 Steinberg Soft und Hardware GmbH, All Rights Reserved
 *
 * ==================================================
 */

#include "mdaPianoCommon.h"
#include "mdaPiano.h"

#include <stdio.h>
#include <math.h>

#define STRING_BUF 2048
static const char* sample_file = "samples.raw";


mdaPiano::mdaPiano(double rate)
  : LV2::Synth<mdaPianoVoice, mdaPiano>(p_n_ports, p_midi) {

  cmax = 0x7F;  //just in case...

  load_samples(&waves);
  load_kgrp(kgrp);

  notes[0] = EVENTS_DONE;
  cpos = sustain = activevoices = 0;
  comb = new float[256];

  update();
  suspend();
}


void mdaPiano::update()  //parameter change
{
  float * param = programs[curProgram].param;
  size = (uint32_t)(12.0f * param[2] - 6.0f);
  sizevel = 0.12f * param[3];
  muffvel = param[5] * param[5] * 5.0f;

  velsens = 1.0f + param[6] + param[6];
  if(param[6] < 0.25f) velsens -= 0.75f - 3.0f * param[6];

  fine = param[9] - 0.5f;
  random = 0.077f * param[10] * param[10];
  stretch = 0.000434f * (param[11] - 0.5f);

  cdep = param[7] * param[7];
  trim = 1.50f - 0.79f * cdep;
  width = 0.04f * param[7];  if(width > 0.03f) width = 0.03f;

  poly = 8 + (uint32_t)(24.9f * param[8]);
}


void mdaPiano::resume()
{
  Fs = getSampleRate();
  iFs = 1.0f / Fs;
  if(Fs > 64000.0f) cmax = 0xFF; else cmax = 0x7F;
  memset(comb, 0, sizeof(float) * 256);
}


void mdaPiano::setParameter(uint32_t index, float value)
{
  programs[curProgram].param[index] = value;
  update();
}


void mdaPiano::process(float **inputs, float **outputs, uint32_t sampleFrames)
{
  float* out0 = outputs[0];
  float* out1 = outputs[1];
  uint32_t event=0, frame=0, frames, v;
  float x, l, r;
  uint32_t i;

  while(frame<sampleFrames)
  {
    frames = notes[event++];
    if(frames>sampleFrames) frames = sampleFrames;
    frames -= frame;
    frame += frames;

    while(--frames>=0)
    {
      VOICE *V = voice;
      l = r = 0.0f;

      for(v=0; v<activevoices; v++)
      {
        V->frac += V->delta;  //integer-based linear interpolation
        V->pos += V->frac >> 16;
        V->frac &= 0xFFFF;
        if(V->pos > V->end) V->pos -= V->loop;
        i = waves[V->pos];
        i = (i << 7) + (V->frac >> 9) * (waves[V->pos + 1] - i) + 0x40400000;
        x = V->env * (*(float *)&i - 3.0f);  //fast int->float

        V->env = V->env * V->dec;  //envelope
        V->f0 += V->ff * (x + V->f1 - V->f0);  //muffle filter
        V->f1 = x;

        l += V->outl * V->f0;
        r += V->outr * V->f0;

        V++;
      }
      comb[cpos] = l + r;
      ++cpos &= cmax;
      x = cdep * comb[cpos];  //stereo simulator

      *out0++ += l + x;
      *out1++ += r - x;
    }

    if(frame<sampleFrames)
    {
      uint32_t note = notes[event++];
      uint32_t vel  = notes[event++];
      noteOn(note, vel);
    }
  }
  for(v=0; v<activevoices; v++) if(voice[v].env < SILENCE) voice[v] = voice[--activevoices];
  notes[0] = EVENTS_DONE;  //mark events buffer as done
}


void mdaPiano::processReplacing(float **inputs, float **outputs, uint32_t sampleFrames)
{
  float* out0 = outputs[0];
  float* out1 = outputs[1];
  uint32_t event=0, frame=0, frames, v;
  float x, l, r;
  uint32_t i;

  while(frame<sampleFrames)
  {
    frames = notes[event++];
    if(frames>sampleFrames) frames = sampleFrames;
    frames -= frame;
    frame += frames;

    while(--frames>=0)
    {
      VOICE *V = voice;
      l = r = 0.0f;

      for(v=0; v<activevoices; v++)
      {
        V->frac += V->delta;  //integer-based linear interpolation
        V->pos += V->frac >> 16;
        V->frac &= 0xFFFF;
        if(V->pos > V->end) V->pos -= V->loop;
        //i = (i << 7) + (V->frac >> 9) * (waves[V->pos + 1] - i) + 0x40400000;   //not working on intel mac !?!
  i = waves[V->pos] + ((V->frac * (waves[V->pos + 1] - waves[V->pos])) >> 16);
  x = V->env * (float)i / 32768.0f;
        //x = V->env * (*(float *)&i - 3.0f);  //fast int->float

        V->env = V->env * V->dec;  //envelope
        V->f0 += V->ff * (x + V->f1 - V->f0);  //muffle filter
        V->f1 = x;

        l += V->outl * V->f0;
        r += V->outr * V->f0;

 if(!(l > -2.0f) || !(l < 2.0f))
 {
   printf("what is this shit?   %d,  %f,  %f\n", i, x, V->f0);
   l = 0.0f;
 }
if(!(r > -2.0f) || !(r < 2.0f))
 {
   r = 0.0f;
 }

        V++;
      }
      comb[cpos] = l + r;
      ++cpos &= cmax;
      x = cdep * comb[cpos];  //stereo simulator

      *out0++ = l + x;
      *out1++ = r - x;
    }

    if(frame<sampleFrames)
    {
      uint32_t note = notes[event++];
      uint32_t vel  = notes[event++];
      noteOn(note, vel);
    }
  }
  for(v=0; v<activevoices; v++) if(voice[v].env < SILENCE) voice[v] = voice[--activevoices];
  notes[0] = EVENTS_DONE;  //mark events buffer as done
}


void mdaPiano::noteOn(uint32_t note, uint32_t velocity)
{
  float * param = programs[curProgram].param;
  float l=99.0f;
  uint32_t  v, vl=0, k, s;

  if(velocity>0)
  {
    if(activevoices < poly) //add a note
    {
      vl = activevoices;
      activevoices++;
    }
    else //steal a note
    {
      for(v=0; v<poly; v++)  //find quietest voice
      {
        if(voice[v].env < l) { l = voice[v].env;  vl = v; }
      }
    }

    k = (note - 60) * (note - 60);
    l = fine + random * ((float)(k % 13) - 6.5f);  //random & fine tune
    if(note > 60) l += stretch * (float)k; //stretch

    s = size;
    if(velocity > 40) s += (uint32_t)(sizevel * (float)(velocity - 40));

    k = 0;
    while(note > (kgrp[k].high + s)) k++;  //find keygroup

    l += (float)(note - kgrp[k].root); //pitch
    l = 22050.0f * iFs * (float)exp(0.05776226505 * l);
    voice[vl].delta = (uint32_t)(65536.0f * l);
    voice[vl].frac = 0;
    voice[vl].pos = kgrp[k].pos;
    voice[vl].end = kgrp[k].end;
    voice[vl].loop = kgrp[k].loop;

    voice[vl].env = (0.5f + velsens) * (float)pow(0.0078f * velocity, velsens); //velocity

    l = 50.0f + param[4] * param[4] * muff + muffvel * (float)(velocity - 64); //muffle
    if(l < (55.0f + 0.25f * (float)note)) l = 55.0f + 0.25f * (float)note;
    if(l > 210.0f) l = 210.0f;
    voice[vl].ff = l * l * iFs;
    voice[vl].f0 = voice[vl].f1 = 0.0f;

    voice[vl].note = note; //note->pan
    if(note <  12) note = 12;
    if(note > 108) note = 108;
    l = volume * trim;
    voice[vl].outr = l + l * width * (float)(note - 60);
    voice[vl].outl = l + l - voice[vl].outr;

    if(note < 44) note = 44; //limit max decay length
    l = 2.0f * param[0];
    if(l < 1.0f) l += 0.25f - 0.5f * param[0];
    voice[vl].dec = (float)exp(-iFs * exp(-0.6 + 0.033 * (double)note - l));
  }
  else //note off
  {
    for(v=0; v<NVOICES; v++) if(voice[v].note==note) //any voices playing that note?
    {
      if(sustain==0)
      {
        if(note < 94 || note == SUSTAIN) //no release on highest notes
          voice[v].dec = (float)exp(-iFs * exp(2.0 + 0.017 * (double)note - 2.0 * param[1]));
      }
      else voice[v].note = SUSTAIN;
    }
  }
}


uint32_t mdaPiano::processEvents(VstEvents* ev)
{
  uint32_t npos=0;

  for (uint32_t i=0; i<ev->numEvents; i++)
  {
    if((ev->events[i])->type != kVstMidiType) continue;
    VstMidiEvent* event = (VstMidiEvent*)ev->events[i];
    char* midiData = event->midiData;

    switch(midiData[0] & 0xf0) //status byte (all channels)
    {
      case 0x80: //note off
        notes[npos++] = event->deltaFrames; //delta
        notes[npos++] = midiData[1] & 0x7F; //note
        notes[npos++] = 0;                  //vel
        break;

      case 0x90: //note on
        notes[npos++] = event->deltaFrames; //delta
        notes[npos++] = midiData[1] & 0x7F; //note
        notes[npos++] = midiData[2] & 0x7F; //vel
        break;

      case 0xB0: //controller
        switch(midiData[1])
        {
          case 0x01:  //mod wheel
          case 0x43:  //soft pedal
            muff = 0.01f * (float)((127 - midiData[2]) * (127 - midiData[2]));
            break;

          case 0x07:  //volume
            volume = 0.00002f * (float)(midiData[2] * midiData[2]);
            break;

          case 0x40:  //sustain pedal
          case 0x42:  //sustenuto pedal
            sustain = midiData[2] & 0x40;
            if(sustain==0)
            {
              notes[npos++] = event->deltaFrames;
              notes[npos++] = SUSTAIN; //end all sustained notes
              notes[npos++] = 0;
            }
            break;

          default:  //all notes off
            if(midiData[1]>0x7A)
            {
              for(uint32_t v=0; v<NVOICES; v++) voice[v].dec=0.99f;
              sustain = 0;
              muff = 160.0f;
            }
            break;
        }
        break;

      default: break;
    }

    if(npos>EVENTBUFFER) npos -= 3; //discard events if buffer full!!
    event++; //?
  }
  notes[npos] = EVENTS_DONE;
  return 1;
}


// TODO: load this from a file
void mdaPiano::load_kgrp(KGRP *kgrp)
{
  //Waveform data and keymapping is hard-wired in *this* version
  kgrp[ 0].root = 36;  kgrp[ 0].high = 37;  kgrp[ 0].pos = 0;       kgrp[ 0].end = 36275;   kgrp[ 0].loop = 14774;
  kgrp[ 1].root = 40;  kgrp[ 1].high = 41;  kgrp[ 1].pos = 36278;   kgrp[ 1].end = 83135;   kgrp[ 1].loop = 16268;
  kgrp[ 2].root = 43;  kgrp[ 2].high = 45;  kgrp[ 2].pos = 83137;   kgrp[ 2].end = 146756;  kgrp[ 2].loop = 33541;
  kgrp[ 3].root = 48;  kgrp[ 3].high = 49;  kgrp[ 3].pos = 146758;  kgrp[ 3].end = 204997;  kgrp[ 3].loop = 21156;
  kgrp[ 4].root = 52;  kgrp[ 4].high = 53;  kgrp[ 4].pos = 204999;  kgrp[ 4].end = 244908;  kgrp[ 4].loop = 17191;
  kgrp[ 5].root = 55;  kgrp[ 5].high = 57;  kgrp[ 5].pos = 244910;  kgrp[ 5].end = 290978;  kgrp[ 5].loop = 23286;
  kgrp[ 6].root = 60;  kgrp[ 6].high = 61;  kgrp[ 6].pos = 290980;  kgrp[ 6].end = 342948;  kgrp[ 6].loop = 18002;
  kgrp[ 7].root = 64;  kgrp[ 7].high = 65;  kgrp[ 7].pos = 342950;  kgrp[ 7].end = 391750;  kgrp[ 7].loop = 19746;
  kgrp[ 8].root = 67;  kgrp[ 8].high = 69;  kgrp[ 8].pos = 391752;  kgrp[ 8].end = 436915;  kgrp[ 8].loop = 22253;
  kgrp[ 9].root = 72;  kgrp[ 9].high = 73;  kgrp[ 9].pos = 436917;  kgrp[ 9].end = 468807;  kgrp[ 9].loop = 8852;
  kgrp[10].root = 76;  kgrp[10].high = 77;  kgrp[10].pos = 468809;  kgrp[10].end = 492772;  kgrp[10].loop = 9693;
  kgrp[11].root = 79;  kgrp[11].high = 81;  kgrp[11].pos = 492774;  kgrp[11].end = 532293;  kgrp[11].loop = 10596;
  kgrp[12].root = 84;  kgrp[12].high = 85;  kgrp[12].pos = 532295;  kgrp[12].end = 560192;  kgrp[12].loop = 6011;
  kgrp[13].root = 88;  kgrp[13].high = 89;  kgrp[13].pos = 560194;  kgrp[13].end = 574121;  kgrp[13].loop = 3414;
  kgrp[14].root = 93;  kgrp[14].high = 999; kgrp[14].pos = 574123;  kgrp[14].end = 586343;  kgrp[14].loop = 2399;
}


void mdaPiano::load_samples(short **buffer)
{
  FILE *f;
  long num, size;
  char filepath[STRING_BUF];

  strncpy(filepath, bundle_path(), STRING_BUF);
  strncat(filepath,
          sample_file,
          STRING_BUF - strlen(filepath));
  f = fopen(filepath, "rb");
  if (f == NULL) {
    fputs("File error", stderr);
    exit(1);
  }

  // obtain file size
  fseek(f, 0, SEEK_END);
  size = ftell(f);
  rewind(f);

  // allocate memory to contain the whole file
  *buffer = (short*) malloc (sizeof(short)*size);
  if (*buffer == NULL) {
    fputs("Memory error", stderr);
    exit(2);
  }

  // copy the file into the buffer
  num = fread(*buffer, 1, size, f);
  if (num != size) {
    fputs ("Reading error", stderr);
    exit (3);
  }
  fclose (f);
  return;
}