<Bresenhan's algorithm>=
public void bresenham (int x0, int y0, int x1, int y1) {
  int A = y_1 - y_0; 
  int B = x_0 - x_1; 
  int g = 2*A + B;
  int diagonalInc = 2*(A+B);
  int rightInc = 2*A;
  int x = x_0;
  int y = y_0;
  while (x <= x_1) {
     plot (x, y);
     if (g >= 0) { // move diagonally
        y += 1;
        g += diagonalIc;
     }
     else g += rightInc;
     x = x + 1;
  }
}