PC World 2008 February/PCWorld_2008-02_cd.bin/audio-video/reaper/reaper2028-install.exe/Effects/LoopSamplers/loopsampler-granul

Text File | 2007-12-03 | 6KB | 249 lines

// This effect Copyright (C) 2004 and later Cockos Incorporated
// License: GPL - http://www.gnu.org/licenses/gpl.html

desc:granular loop sampler (mono)
/* trigger 1 starts recording
    trigger 2 stops recording + looped play
    trigger 3 one off play
*/

slider1:0<-120,12,1>loop volume (dB)
slider2:1<-8,8,0.1>play speed (can be negative)
slider3:1<0,10,1>trigger base (uses x..x+3)
slider4:0<0,30000,1>length (ms)
slider5:1000<0,30000,200>loop granularity (ms)
slider6:16000<0,30000,200>maximum length (ms)
slider7:-120<-120,0,1>silence removal threshold (dB)
slider8:0<0,6,1{stopped,recording,playing looped,playing once,playing looped+recording,playing once+recording>state

/* idle mix=volume when not playing sample
    play mix = mix when playing sample
    record mix = mix of new and old sample
    playlen lets you play only part of the sample

  if you hit button1 and isrec is active, we switch to play, keeping isrec
  active.

  if you hit button1 and isplay is active, we mix in the source signal with
  the sample.


*/



@init
isplay=isrec=recpos=playpos=0;
ext_noinit=1;


@slider
playmix=2 ^ (slider1/6);
trigstart=(2 ^ ((slider3+0.1)|0))|0;
playspeed=slider2;

slider4 < 0 ? slider4=0;
gmaxl=1000000000/srate;
slider4=min(slider4,gmaxl);

granule=(slider5*srate/1000)|0;
maxgran=(slider6*srate/1000)|0;
maxgran > 1000000 ? maxgran = 1000000;

olsize=0;

silthresh=slider7 > -119 ? (2^(slider7/6)) : 0;

vstpos=0*srate/1000;
vreclen=(slider4*srate/1000-vstpos)-olsize;
slider8=lslider8;

@serialize
file_var(0,isplay);
file_var(0,isrec);
file_var(0,recpos);
!isrec ? file_mem(0,0,recpos);

file_avail(0) >= 0 ?(
  a=0;
  slider4=(recpos * 1000 / srate)|0;
  sliderchange(slider4);
);

@block
trigger&(trigstart) ? (
  isplay ? // if playing, switch record and play on
  (
    !isrec ? lastioffs=-1;
    isrec=1;
  )
  :
  (
      isrec ? ( // start playing, but keep recording
         playpos=0;
         isplay=1;
         lastioffs=-1;
      )
      :
      ( // stop playing, start recording
        recpos=isplay=0; isrec=1;
        silstart=-1;
      )
  )
);
trigger&(trigstart*6) ?
(
  isrec ? (
     isplay ?
     (
       isrec=0;
     )
     :
     (
       // switch to playback
       playpos=isrec=0;
       isplay=vreclen > 4 ? (trigger&(trigstart*4) ? 2 : 1) : 0;

       orecpos=recpos;

       recpos = (((silstart + granule/2) / granule)|0) * granule;
       recpos < granule ? recpos=granule;
       recpos > maxgran ? recpos=maxgran;

        slider4=(recpos * 1000 / srate)|0;
        sliderchange(slider4);
        vreclen=(slider4*srate/1000-vstpos)-olsize;

       // figure out what the delta between where we need to be and where we
       // are is

       // how many samples we went over
       delta=((orecpos-recpos)*abs(playspeed))%granule;
       delta > 0 ? (
         playpos=playspeed > 0 ? delta : vreclen-delta;
       ); // eat the samples

       freembuf(recpos); // free any unused memory
     )
  ) : (
     isplay && !(trigger&(trigstart*4)) ? isplay=0 : (
       // start over playback
       playpos=0;
       isplay=vreclen > 4 ? (trigger&(trigstart*4)?2:1) : 0;
     )
  )
);

lslider8=slider8;
isplay ?
(
  isrec ?
  (
    slider8=3+isplay;
  )
  :
  slider8=1+isplay;
) : (
  slider8=isrec?1:0;
);

slider8!=lslider8 ?
(
  lslider8=slider8;
  sliderchange(slider8);
)

@sample

// if recording, record, and if we run out of
// buffer, switch mode to looped playback
isrec ? (

    isplay ?
    (
       offs = playspeed<0?vreclen-playpos:playpos;
       ioffs=offs|0; // fr=offs-ioffs;
       lastioffs < 0 ?
       (
         vstpos[ioffs] += spl0;
         lastioffs=ioffs;
       )
       :
       (
          cnt=0;
          mcnt=(abs(playspeed)+0.9)|0;
           while(
             ioffs != lastioffs ?
             (
               //update current sample with our sample, but only once
               //maybe get around this by just adding spl0*(1-fr)
              vstpos[lastioffs] += spl0;
              lastioffs+=sign(playspeed);
              lastioffs < 0 ? (lastioffs=vreclen-1) : (lastioffs >= vreclen ? lastioffs=0);
            );
            ioffs != lastioffs && (cnt+=1) < mcnt;
          ) // while
       )
    )
    :
    (
      recpos >= maxgran ?
      (
        isplay=1;
        playpos=isrec=0;

        recpos = (((silstart / granule) + granule/2)|0) * granule;
        recpos < granule ? recpos=granule;
        recpos > maxgran ? recpos=maxgran;

        slider4=(recpos * 1000 / srate)|0;
        sliderchange(slider4);
        vreclen=(slider4*srate/1000-vstpos)-olsize;
      ) : (
        recpos[0]=spl0;
        recpos+=1;

        abs(spl0) >= silthresh ?
        (
          silstart < 0 ?
          (
            recpos=1;
            recpos[-1]=spl0;
            vstpos=0;
          );
          silstart=recpos;
        );
        slider4=(silstart * 1000 / srate)|0;
        sliderchange(slider4);
        vreclen=(silstart-vstpos)-olsize;
      );
    );
); // if isrec


// if isplay = 1, loop playback
// if isplay = 2, one shot playback
isplay ? (
   isplay==2 || olsize <= playpos ? (
       offs = playspeed<0?vreclen-playpos:playpos;
       ioffs=offs|0; fr=offs-ioffs;
       spl0=spl0 + (vstpos[ioffs]*(1-fr)+vstpos[ioffs+1]*fr)*playmix; // one shot gets no overlap
   ) : (
       tmpmix=playpos/olsize;
       offs=playspeed<0?vreclen-playpos:playpos;
       ioffs=offs|0; fr=offs-ioffs;
       spl0=spl0 + (vstpos[ioffs]*(1-fr)+vstpos[ioffs+1]*fr)*playmix*tmpmix; // overlap with self
       offs=playspeed<0?playpos:vreclen+playpos;
       ioffs=offs|0; fr=offs-ioffs;
       spl0=spl0 + (vstpos[ioffs]*(1-fr)+vstpos[ioffs+1]*fr)*playmix*(1-tmpmix); // overlap with self
    );

    spl1=spl0;

    isplay == 2 ? (
      playpos+abs(playspeed) > vreclen ? isrec=isplay=playpos=0 : playpos=playpos+abs(playspeed);
    ) : (
      playpos=playpos+abs(playspeed)>vreclen?0:playpos+abs(playspeed);
    )
);