and those paying attention would point out to me my error:
SQRT(POW( ABS( X(geometry) - X( GeomFromText('POINT(43.3723651907 5.4)') )), 2) + POW( ABS(Y(geometry) - Y( GeomFromText('POINT(43.3723651907 5.4)') )), 2 ))
those POINT() values should be the center of the polygon, not the top left corner, as shown there
