cam_pos      = [0.308932, 0.615129, -0.254913]';
cam_dir      = [0.860739, 0.345784, 0.37358]';
cam_up       = [-0.495728, 0.402612, 0.769517]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.153853, 1.12724, -0.688885]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;