cam_pos      = [-0.727814, 1.47953, 0.318605]';
cam_dir      = [0.980483, -0.119876, 0.155832]';
cam_up       = [0.0870801, 0.975413, 0.20245]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.234438, 0.245956, -1.28586]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;