function [nbNode, obstacle, points] = buildRRT()
  clc
  close all
  
  S = [2, 0];
  G = [-2, 0];
  [Sq1, Sq2] = MyIK(2,1,S(1),S(2)); %-28.995   104.48
  [Gq1, Gq2] = MyIK(2,1,G(1),G(2)); %151.04    104.48
  randVmin = -180;
  randVmax = 180;
  L1 = 2;
  L2 = 1;
  
  q1_1st = randVmin + (randVmax - randVmin)* rand();
  q2_1st = randVmin + (randVmax - randVmin)* rand();
  
  
  [x, y]=MyFK(L1,L2,q1_1st,q2_1st);  
  points = [Sq1 Sq2 S(1) S(2)]'; 
  
  GapValue = 5;
  distArr = [];
  pdefL = 50;
  
  figure 1
  axis([-180 180 -180 180])
  hold on
  plot(points(1, 1), points(2, 1))
  text(points(1, 1), points(2, 1), 'S', 'FontSize', 20);
  
  minTable = [];
  
  n=0;
  WhileCond = 15;
  
  while n<WhileCond
    distArr = [];
    
    q1_r = randVmin + (randVmax - randVmin)* rand();
    q2_r = randVmin + (randVmax - randVmin)* rand();
    
    
    [x, y]=MyFK(L1,L2,q1_r,q2_r);        
    
    n = columns(points);
    
    minTable(1, n) = inf;
    obstacle(n,n) = NaN;
    if n==WhileCond
      q1_r = Gq1;
      q2_r = Gq2;
      for j=1:n
          q1_p = points(1,j);
          q2_p = points(2,j);
       
          pointsTemp = [points [q1_r q2_r 0 0]']; %new point r values are stored in n+1 column of pointsTemp
          distArr = [distArr checkingLine(GapValue, L1, L2, n+1, j, pointsTemp)];
      endfor
      if isnan(min(distArr))
        WhileCond++;
      else
        pdefL = min(distArr);
      endif
    elseif n > 1
      for j=1:n
          q1_p = points(1,j);
          q2_p = points(2,j);
       
          pointsTemp = [points [q1_r q2_r 0 0]']; %new point r values are stored in n+1 column of pointsTemp
          distArr = [distArr checkingLine(GapValue, L1, L2, n+1, j, pointsTemp)];
      endfor
      
    else
      q1_p = points(1,1);
      q2_p = points(2,1);
      pointsTemp = [points [q1_r q2_r 0 0]'];
      distArr = [distArr checkingLine(GapValue, L1, L2, 1, 2, pointsTemp)];
    
    endif
    [minDist, minIndex] = min(distArr); %validé
      
    if ~isnan(minDist)
      q1_p = points(1, minIndex);
      q2_p = points(2, minIndex);
      
      q1_pdefL = q1_p + (pdefL * (q1_r - q1_p) / minDist);
      q2_pdefL = q2_p + (pdefL * (q2_r - q2_p) / minDist); % from thales theorem
      
      points(1, n+1) = q1_pdefL;
      points(2, n+1) = q2_pdefL;
      
      if n+1!=minIndex
        obstacle(n+1, minIndex) = pdefL;
        obstacle(minIndex, n+1) = pdefL;
      endif
      
      figure 1
      hold on
      plot(points(1, n), points(2, n))
      if pdefL == min(distArr) %which occurs only at the last iteration
        text(points(1, n+1), points(2, n+1), 'G', 'FontSize', 20);
      endif
      if n>1
        text(points(1, n), points(2, n), int2str(n-1), 'FontSize', 20);
      endif
      Xplot = [q1_p, q1_pdefL];
      Yplot = [q2_p, q2_pdefL];
      plot(Xplot, Yplot, 'Color', 'b')
      drawnow
    endif
  endwhile
endfunction