function [controlPoints, contour] = annealer(imageFile, tempVect, sampleNum, spacing)

% Main function of the Simulated Annealing program.
% Finds a contour traversing the image from side to side by a simulated
% annealing algorithm.
% 
% syntax:
% [controlPoints, contour] = annealer(imageFile, tempVect, sampleNum, spacing)
% 
% input/output variables:
% imageFile         name of the file containing the image
% tempVect          vector of (descending) temperatures
% sampleNum         number of samples at each step
% spacing           horizontal spacing between control points
%
% controlPoints     the vector of control points
% contour           the vector of contour points


% Read the image and compute its potential energy
I = rgb2gray(imread(imageFile));
U = potentialEnergy(I);

% Initialize auxiliary variables
[nRows, nCols] = size(I);
nControlPoints = floor( nCols / spacing ) + 3;

% Initialize the array of controlpoints and the contour
controlPoints = nRows / 2 * ones(nControlPoints, 1);
contour = formBspline(controlPoints, spacing);

% Main loop
for Temp = TempVect,  
    % Choose a random order to follow in visiting the control points
    order = randperm(nControlPoints);
    
    % Adjust each control point once following the order
    for j = 1:nControlPoints,
        [controlPoints, contour] = ...
            gibbsSampler(U,controlPoints,contour,spacing,Temp,order(j),sampleNum);   
    end
end