Halcon using skeleton extraction operator Skeleton calculate the slope of region

How do you calculate the slope of a region?
If the normal region,orientation_region can calculate the azimuth of the region based on the Elliptic_axis. However, if it is an irregular region, please note that the operator's calculation of the position is likely to be a large deviation from the position you think.
At this point, the more general approach is:
(1) The skeleton operator can fit the skeleton of the region.
(2) Take the longest segment of the skeleton as the central axis of the region.
(3) The slope can be calculated using Line_orientation.