Akso - Audio DSP Platform

lmangle mod

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drives a phasor (saw-wave) for reading/writing data. phase always stays inside the range defined by 'offset' and 'range'

Author: robert schirmer

License: BSD

Github: rbrt/old/lmangle mod.axo

Inlets

frac32.bipolar speed modulation

frac32buffer.positive looplength

frac32buffer.positive loopstart inside 'range'

bool32.risingfalling play or dont

bool32.rising reset to 'startpoint'

frac32.positive offset inside the table

frac32.positive length of the area to index,or loop end

frac32.positive start position on 'reset' inside 'range'

Outlets

int32 loop count since reset

int32 lenght of the loop in samples

frac32buffer.positive phase

Parameters

frac32.u.map range

frac32.u.map looplength

frac32.u.map loopstart

frac32.s.map speed,+ 64 normal speed forward, - 64 backward

bool32.tgl loop changes direction when it reaches the boundaries

Attributes

objref table

Declaration

float32_t index;
bool play;
int direction;
int dir1;
int dir2;
uint32_t pos;
int shift;
int range;
int startpoint;
int loopstart;
int looplength;
int count;
int edge;
int r;
bool add;
int max_pos;

Init

play = 0;

// set 'shift factor' for storing the recording length/the sync output
if (attr_table.LENGTH == 2048) {
  shift = 16;
}
if (attr_table.LENGTH == 4096) {
  shift = 15;
}
if (attr_table.LENGTH == 8192) {
  shift = 14;
}
if (attr_table.LENGTH == 16384) {
  shift = 13;
}
if (attr_table.LENGTH == 32768) {
  shift = 12;
}
if (attr_table.LENGTH == 65536) {
  shift = 11;
}
if (attr_table.LENGTH == 131072) {
  shift = 10;
}
if (attr_table.LENGTH == 262144) {
  shift = 9;
}
if (attr_table.LENGTH == 524288) {
  shift = 8;
}
if (attr_table.LENGTH == 1048576) {
  shift = 7;
}
if (attr_table.LENGTH == 2097152) {
  shift = 6;
}
if (attr_table.LENGTH == 4194304) {
  shift = 5;
}

Audio Rate

int t_range = (inlet_range + param_range);
int t_length = (inlet_looplength + param_looplength);
int t_speed = (inlet_speed + param_speed);

range = (t_range >> shift);
looplength = ((___SMMUL(t_range, t_length) << 5) >> shift);
loopstart =
    ((___SMMUL(t_range, (inlet_loopstart + param_loopstart)) << 5) >> shift);
max_pos = (range < (loopstart + looplength)) ? range : (loopstart + looplength);
dir1 = (t_speed < 0) ? 1 : -1;
dir2 = (t_speed > 0) ? 1 : -1;

if (inlet_reset && r) {
  index = 0;
  r = 0;
} else if (!inlet_reset)
  r = 1;

if (inlet_play && (!play)) {
  play = 1;
  edge = 0;
  count = 0;
  direction = 1;
  add = range;
  startpoint = ((___SMMUL(t_range, inlet_startpoint) << 5) >> shift);
  if (param_palindromic && (t_speed < 0)) {
    index = (max_pos);
    startpoint = 1;
  } else
    index = 0;

} else {
  if (!inlet_play) {
    play = 0;
    outlet_pos = 0;
  }

  index += ((t_speed * direction) * (float)(1.0f / (1 << 27)));
  pos = (index + startpoint);

  // limit indexing to a range
  if (play) {
    if (pos >= max_pos) {
      if (param_palindromic) {
        direction = dir1;
        if (!edge)
          index = (max_pos - loopstart);
      } else
        index = 0;
      count += add;
      edge = 1;
    }
    if (pos <= startpoint) {
      if (param_palindromic) {
        direction = dir2;
      } else
        index = (max_pos - startpoint);
      count += add;
      edge = 1;
    }
    if (edge) {
      startpoint = loopstart;
    }
    outlet_pos = ((pos << shift) + inlet_offset);
  }
}
outlet_count = count;
outlet_smps = (max_pos - loopstart);