do you see here any issue with this procedure and how to call it
DELIMITER //
CREATE PROCEDURE generate_track_polygons()
BEGIN
    DECLARE done INT DEFAULT FALSE;
    DECLARE curr_id, seg_id INT DEFAULT 0;
    DECLARE curr_lon, curr_lat, prev_lon, prev_lat DECIMAL(12,8);
    DECLARE curr_course, prev_course DECIMAL(6,3);
    DECLARE curr_time, start_time, end_time DATETIME(6);
    DECLARE meters_per_degree DECIMAL(16,12) DEFAULT 111320.0 * COS(RADIANS(50.0)); -- For ~50°N latitude
    
    -- Cursor for ordered high-precision points
    DECLARE point_cur CURSOR FOR 
        SELECT 
            id, longitude, latitude, course, timestamp
        FROM precise_track_points 
        ORDER BY timestamp;
    
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
    
    -- Temporary tables for processing
    CREATE TEMPORARY TABLE IF NOT EXISTS temp_segments (
        seg_id INT AUTO_INCREMENT PRIMARY KEY,
        polygon GEOMETRY,
        avg_course DECIMAL(6,3),
        start_time DATETIME(6),
        end_time DATETIME(6)
    ) ENGINE=Memory;
    
    CREATE TEMPORARY TABLE IF NOT EXISTS temp_final_polygons (
        polygon GEOMETRY,
        avg_course DECIMAL(6,3),
        start_time DATETIME(6),
        end_time DATETIME(6)
    ) ENGINE=Memory;
    
    OPEN point_cur;
    FETCH point_cur INTO curr_id, curr_lon, curr_lat, curr_course, curr_time;
    SET prev_lon = curr_lon;
    SET prev_lat = curr_lat;
    SET prev_course = curr_course;
    SET start_time = curr_time;
    
    read_loop: LOOP
        -- Calculate 2m offsets (precise at ~50°N latitude)
        SET @offset = 2.0 / meters_per_degree;
        SET @left_lon = curr_lon - @offset * SIN(RADIANS(curr_course));
        SET @left_lat = curr_lat + @offset * COS(RADIANS(curr_course));
        SET @right_lon = curr_lon + @offset * SIN(RADIANS(curr_course));
        SET @right_lat = curr_lat - @offset * COS(RADIANS(curr_course));
        
        -- Start new segment if course changes >10° or first point
        IF seg_id = 0 OR ABS(curr_course - prev_course) > 10.0 THEN
            IF seg_id > 0 THEN
                -- Finalize previous segment
                INSERT INTO temp_segments (polygon, avg_course, start_time, end_time)
                VALUES (
                    create_segment_polygon(seg_id),
                    (SELECT AVG(course) FROM precise_track_points 
                     WHERE timestamp BETWEEN start_time AND end_time),
                    start_time,
                    end_time
                );
            END IF;
            
            -- Start new segment
            SET seg_id = seg_id + 1;
            SET start_time = curr_time;
            
            -- Initialize linestrings for new segment
            INSERT INTO temp_segments VALUES (seg_id, NULL, NULL, NULL, NULL);
            INSERT INTO temp_left_points (seg_id, point) VALUES (seg_id, ST_Point(@left_lon, @left_lat));
            INSERT INTO temp_right_points (seg_id, point) VALUES (seg_id, ST_Point(@right_lon, @right_lat));
        ELSE
            -- Continue current segment
            INSERT INTO temp_left_points (seg_id, point) VALUES (seg_id, ST_Point(@left_lon, @left_lat));
            INSERT INTO temp_right_points (seg_id, point) VALUES (seg_id, ST_Point(@right_lon, @right_lat));
            SET end_time = curr_time;
        END IF;
        
        SET prev_lon = curr_lon;
        SET prev_lat = curr_lat;
        SET prev_course = curr_course;
        FETCH point_cur INTO curr_id, curr_lon, curr_lat, curr_course, curr_time;
        IF done THEN
            LEAVE read_loop;
        END IF;
    END LOOP;
    
    -- Finalize last segment
    IF seg_id > 0 THEN
        INSERT INTO temp_segments (polygon, avg_course, start_time, end_time)
        VALUES (
            create_segment_polygon(seg_id),
            (SELECT AVG(course) FROM precise_track_points 
             WHERE timestamp BETWEEN start_time AND end_time),
            start_time,
            end_time
        );
    END IF;
    
    -- Merge overlapping/adjacent polygons
    INSERT INTO temp_final_polygons
    WITH merged AS (
        SELECT 
            ST_Union(polygon) AS merged_poly,
            MIN(start_time) AS start_time,
            MAX(end_time) AS end_time,
            AVG(avg_course) AS avg_course
        FROM temp_segments
        GROUP BY ST_ClusterDBSCAN(polygon, 5.0, 1) OVER ()  -- 5m max distance between polygons
    )
    SELECT merged_poly, avg_course, start_time, end_time FROM merged;
    
    -- Return final results
    SELECT 
        ST_AsGeoJSON(polygon) AS polygon_geojson,
        avg_course,
        start_time,
        end_time,
        ST_Area(polygon) AS area_sqm
    FROM temp_final_polygons;
    
    -- Cleanup
    DROP TEMPORARY TABLE IF EXISTS temp_segments;
    DROP TEMPORARY TABLE IF EXISTS temp_left_points;
    DROP TEMPORARY TABLE IF EXISTS temp_right_points;
    DROP TEMPORARY TABLE IF EXISTS temp_final_polygons;
    CLOSE point_cur;
END //

CREATE FUNCTION create_segment_polygon(seg_id INT) RETURNS GEOMETRY
DETERMINISTIC
BEGIN
    DECLARE left_line, right_line, polygon GEOMETRY;
    
    SELECT ST_MakeLine(point ORDER BY id) INTO left_line
    FROM temp_left_points WHERE seg_id = seg_id;
    
    SELECT ST_MakeLine(point ORDER BY id DESC) INTO right_line  -- Reverse order
    FROM temp_right_points WHERE seg_id = seg_id;
    
    SET polygon = ST_MakePolygon(ST_AddPoint(left_line, right_line));
    RETURN polygon;
END //
DELIMITER ;