Return the union of the materialised polygons across the trgeometry's time domain

traversedArea(trgeometry [, unary_union boolean = true]) → geometry

SELECT ST_AsText(traversedArea(
  trgeometry 'Polygon((0 0,1 0,1 1,0 1,0 0));[Pose(Point(0 0), 0.0)@2001-01-01, Pose(Point(10 0), 0.0)@2001-01-02]'));
-- POLYGON((0 0, 11 0, 11 1, 0 1, 0 0))

With unary_union = false the function returns a GeometryCollection of the per-instant materialised polygons without dissolving them, useful when the caller wants to do its own post-processing.

Sampling caveat: the implementation samples at the input instants, so pure-translation segments are exact but the swept ribbon between two instants where a rotation happens is approximated by the convex hull of the two endpoint polygons. Up-sampling the tpose before constructing the trgeometry tightens the approximation.