cam_pos      = [0.380735, 1.8245, 0.830428]';
cam_dir      = [-0.935111, -0.273074, 0.225826]';
cam_up       = [-0.318888, 0.370592, -0.872337]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.205516, 1.1807, 0.57672]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;