Songlib: trill

John C. Lusth

Revision Date: November 7, 2011

Printable Version

The trill family of functions is used to play notes with trill (a cyclical varying of pitch at the end of a note). The trill family follows the {n,r,d} convention.

void trill(double beats,int, instrument,int octave,int pitch,
    double startBeats,double delta,double down,double up,int count);

void ntrill(double beats,int instrument,int numberedNote,
    double startBeats,double delta,double down,double up,int count);

void rtrill(double beats,RRA *r,
    double startBeats,double delta,double down,double up,int count);

void dtrill(double beats,int *data,int length,
    double startBeats,double delta,double down,double up,int count);

The note plays for startBeats and then oscillates 'count' times around down and up. Each down phase lasts delta beats and each up phase lasts delta beats. Down and up are specified as offsets. For example, if the specified note is C3, down is -STEP and up is STEP, then the note will start at C3 and then oscillate between B2 and Cs3.

A trill is usually considered a rapid alternation between adjacent notes; the trill function provides more generality than that.

lusth@cs.ua.edu