cam_pos      = [-0.146714, 1.45582, 0.830543]';
cam_dir      = [0.637234, 0.0334586, 0.769944]';
cam_up       = [-0.0508353, 0.998706, -0.00132647]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [1.02276, 0.0509325, -0.848686]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;