**Algorithm 1. CIDP (Compute initial set of dominant points).**

Input: The inputs are the coordinates of the boundary points. *Cd* = pi (xi,yi),*i*=1,2,3 … ..*n*; *n* boundary points. Output: The outputs are the curve indices of initial dominant points. **Begin** Case 1: i=0 If (x(0)-x(n-1) != x(1)-x(0)) or ((y(1)-y(0) != y(0)-y(n-1)) then D[0]= 0; Case 2: i=n-1 If (x(n-1)-x(n-2) != x(0)-x(n-1)) or (y(n-1)-y(n-2) != y(0)-y(n-1)) D[j]=i; Default: While (i<*n*-1) If (x(i)-x(i-1) != x(i+1)-x(i)) or (y(i+1)-y(i) != y(i)-y(i-1)) D[j] = i **End.**
