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I wrote a function that creates arbitrary quadrants within a polygon

SELECT (quadrant(20,0.0,90)).*

The first parameter is the polygon ID, the second one is the start angle and with the third one the quadrant is finally spanned.

First the TYPE

CREATE TYPE quadrant AS (id smallint,geom geometry(polygon,31468))

Here is the function

CREATE OR REPLACE FUNCTION quadrant(id integer,start double precision, stop integer) RETURNS SETOF quadrant AS $$
WITH centroid AS
(SELECT
    accumulation.partnumber,
    (ST_Centroid(accumulation.geom)) AS vertex
FROM accumulation
    WHERE partnumber=$1
),
newline AS
(SELECT 
ST_SetSRID(ST_Translate(
                ST_Rotate(
                    ST_MakeLine(
                          ST_MakePoint(0.0,2000.0), 
                          ST_MakePoint(0.0,0.0)),
                radians(($2+s.a)*-1)),
          ST_X(vertex), ST_Y(vertex)),
ST_SRID(vertex)) AS geom
FROM centroid, generate_series(0,$3,$3) AS s(a)
),
span AS
(SELECT
    centroid.partnumber,
    ST_LineMerge(ST_Union(newline.geom)) AS geom
FROM newline, centroid
    GROUP BY partnumber),
multiobject AS
(SELECT
    span.partnumber,
    ST_Split(accumulation.geom,span.geom) AS geom,
    generate_series(1,100) AS n
FROM span, accumulation
    WHERE accumulation.partnumber=$1),
objects AS
(SELECT
    n,
    ST_GeometryN(multiobject.geom,n) AS geom
FROM multiobject
    WHERE n <= ST_NumGeometries(multiobject.geom))

SELECT
    partnumber AS id,
    objects.geom
FROM objects, multiobject
    WHERE multiobject.n <= ST_NumGeometries(multiobject.geom)
        ORDER BY LEAST(ST_Area(ST_GeometryN(objects.geom,multiobject.n)))
            LIMIT 1
$$ LANGUAGE 'sql';

I applied this function for 300 polygons and I noticed a problem. My last query results the smallest piece from the split. But in some cases, when the first newline (see subquery newline) crosses the polygon more than one time, there is a smaller piece that represents the quadrant (see the most right object in the picture below).

The query doesn't calculate the right quadrant for the left object in the picture. In this case the smaller area of the split is not the quadrant, because the polygon is plumped to the northeast direction.

So my question is, how I can enhance my query to avoid these incorrect quadrants. Maybe I have to overthink the function generally.

enter image description here

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