cam_pos      = [0.137288, 1.7493, 0.837536]';
cam_dir      = [-0.44261, -0.142579, 0.885306]';
cam_up       = [-0.542802, 0.828453, -0.137952]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.949309, 0.720335, 0.590618]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;