cam_pos      = [-0.488703, 1.00932, 1.68889]';
cam_dir      = [0.880645, 0.463479, -0.0982405]';
cam_up       = [-0.423441, 0.862985, 0.275598]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.282644, 0.26747, -1.2718]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;