an open-source digital signal processing and sound synthesis language
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table/tablei/tableset

initialize and access a function table slot

    [note: These are older function table slot routines. They have been generally superceded by using the Ooscili or Ooscil objects to read a function table slot for a control function/envelope for exactly one cyle through the note.

Synopsis

    #include "ugens.h"

    float table(nsample,array,tab)
    long nsample;
    float *array,*tab;

    float tablei(nsample,array,tab)
    long nsample;
    float *array,*tab;

    tableset(dur,size,tab)
    float dur,*tab;
    int size;

Description

These units will return a value from the *array as a function of nsample, which is the number of the current sample, counting up from 0. The array *tab must be dimensioned at 2 in the calling routine. It is used for bookkeeping purposes. tableset initializes the values in the *tab array as functions of dur, which is the expected duration of the note, and size, which is the number of locations in the array to be sampled. The values in *tab are left untouched by table and tablei so they can be called to look at any tables of the same size. tablei is an interpolating version of table.

The value of these units is that they do not need to be called on every sample and can thus be used in control loops to create amplitude curves etc. For example:

          long nsample,totalsamps;
          short countdown,loopsize,size;
          float amp,array[???],tab[2],dur;
          .
          .
          tableset(dur,size,tab);
          .
          .
          for(i = 0; i < framesToRun(); i++) {
                                   /* main performance loop */
               if(!countdown--) {
                                   /* periodic control loop */
                    amp = table(currentFrame(), array, tab);
                    countdown = loopsize;
               }
               .
               .
          }
          .
          .
          .
If nsample points to a time greater than than that declared by dur the last value in the array will be returned.

See Also

env, Ooscili,

Bugs

Not sure what will happen if negative times or samples are passed in argument list.