// Trace one contour starting at (xS,yS)
// in direction dS with label label
// trace one contour starting at (xS,yS) in direction dS
Contour traceContour(int xS, int yS, int label, int dS, Contour cont) {
int xT, yT; // T = successor of starting point (xS,yS)
int xP, yP; // P = previous contour point
int xC, yC; // C = current contour point
Point pt = new Point(xS, yS);
int dNext = findNextPoint(pt, dS);
cont.addPoint(pt);
xP = xS;
yP = yS;
xC = xT = pt.x;
yC = yT = pt.y;
boolean done = (xS == xT && yS == yT); // true if isolated pixel
while (!done) {
labelArray[yC][xC] = label;
pt = new Point(xC, yC);
int dSearch = (dNext + 6) % 8;
dNext = findNextPoint(pt, dSearch);
xP = xC;
yP = yC;
xC = pt.x;
yC = pt.y;
// are we back at the starting position?
done = (xP == xS && yP == yS && xC == xT && yC == yT);
if (!done) {
cont.addPoint(pt);
}
}
return cont;
}
