/* Equal temperament scale count variables. A standard to remember: all variations of C
are considered to be at the start of a scale, and all variations of B at the end of it*/

#define Cbnote -1
#define Cnote  0
#define Csnote 1
#define Dbnote 1
#define Dnote  2
#define Dsnote 3
#define Ebnote 3
#define Enote  4
#define Esnote 5
#define Fbnote 4
#define Fnote  5
#define Fsnote 6
#define Gbnote 6
#define Gnote  7
#define Gsnote 8
#define Abnote 8
#define Anote  9
#define Asnote 10
#define Bbnote 10
#define Bnote  11
#define Bsnote 12

#define BASE 3600/TEMPO 

/* TEMPO must be defined before #including notes.h. The following
note lengths apply in the case where the quarter note is the basic beat 
length of the piece. */

#define QUAR  BASE
#define QUARTRIP BASE*4/3
#define HALF  BASE*2
#define WHOL  BASE*4
#define EIGH  BASE/2
#define EIGHTRIP BASE*4/12
#define SIXT  BASE/4
#define THIR  BASE/8

#define CNOTEREF 261.643286573146

/* The following #define is a macro that assigns a triplet structure to an element of
the Tones array, used by the SWsynth */
#define ASSIGN(_tone,_count,_amplitude,_duration)\
  _tone.count=_count;\
  _tone.amplitude=_amplitude;\
  _tone.duration=_duration;
  
  
const double noteEqualRatios[12]={1.0,
                            1.059463094359,
                            1.122462048309,
                            1.189207115003,
                            1.259921049895,
                            1.334839854170,
                            1.414213562373,
                            1.498307076877,
                            1.587401051968,
                            1.681792830507,
                            1.781797436281,
                            1.887748625363};
                   
/* MakeNote returns the count value used in a tone struct */
int MakeNote(int note, int octaveOffset);
int MakeNote(int note, int octaveOffset)
  {  
  /*octaveOffset is the octave related to the middle-C one. 
    Middle-C octave would be 0, the one below, -1, etc     */
  double temp;
  int i;
  
  if(note<-1 || note>12) return 0;
  
  if(note==-1)
    {
    octaveOffset--;
    note=11;
    }
  if(note==12)
    {
    octaveOffset++;
    note=0;
    }
    
  temp=CNOTEREF*noteEqualRatios[note]; /* Yields note in middle-C octave*/
  
  if(octaveOffset<0) for(i=0;i>octaveOffset;i--) temp/=2;
  if(octaveOffset>0) for(i=0;i<octaveOffset;i++) temp*=2;
  
  temp=783360/temp;
  temp+=0.5; /*round up*/
  return (int)temp;
  }