cam_pos      = [0.264094, 1.72573, 0.829154]';
cam_dir      = [-0.935111, -0.273074, 0.225826]';
cam_up       = [-0.322583, 0.392263, -0.861435]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.195047, 1.16825, 0.605016]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;