Flute acoustics: measurement, modelling and design - School of ...

APPENDIX B. PROGRAM LISTINGS 322
int n = 0, cellCount = 0;
UnitCell cell;
BoreSegment s;
double radius;
if(x == 0) {
*Z0 = charZ(w->head->embouchureHole->c,
w->head->embouchureHole->rho,
w->head->embouchureHole->boreRadius);
*c = w->head->embouchureHole->c;
return 1;
}
if (x > 0) {
/* find the bore or hole at the point x */
bore = w->head->downstreamBore;
/* if x is outside of the current bore, try the next one */
while(x >= boreLength(bore) && cellCount < sizeVector(w->cells)) {
/* subtract from x the length of the previous bore */
x -= boreLength(bore);
/* find the next bore */
cell = (UnitCell)elementAt(w->cells, cellCount++);
bore = cell->bore;
}
}
else if (x < 0) {
bore = w->head->upstreamBore;
x = -x;
}
/* if we are at a hole */
if(x == 0) {
*Z0 = charZ(cell->hole->c, cell->hole->rho,
cell->hole->boreRadius);
*c = cell->hole->c;
return 1;
}
/* otherwise, find the correct BoreSegment */
else {
s = (BoreSegment)elementAt(bore, n);
while(x > s->length) {
/* subtract from x the length of the previous segment */
x -= s->length;
/* get the next segment */
s = (BoreSegment)elementAt(bore, ++n);
}
}
/* if x is outside the BoreSegment, return 0 */
if(x > s->length) return 0;
/* otherwise do a linear interpolation */
else {
radius = (s->radius2 * x + s->radius1 * (s->length - x))
/ (s->length);
}
*Z0 = charZ(s->c, s->rho, radius);
*c = s->c;
return 1;
}
double boreLength(Vector bore) {