code: public static void assignLine(List<Point2D_I32> contour, int indexA, int indexB, LineParametric2D_F64 line) {
  		Point2D_I32 endA = contour.get(indexA);
  		Point2D_I32 endB = contour.get(indexB);
  
  		line.p.x = endA.x;
  		line.p.y = endA.y;
  		line.slope.x = endB.x-endA.x;
  		line.slope.y = endB.y-endA.y;
  	}
docs: Assigns the line so that it passes through points A and B.