Moving/shifting lines parallel to the original object

A common requirement for spatial data processing is to move a linear object parallel to itself. Examples include the desire to create a linestring that is parallel to the boundary of a land parcel, as is the case with rights of carriageway, often defined as being 10ft from an existing boundary. Similarly, one often hears of the need to create a line parallel to an existing road centerline; perhaps to define the boundaries of the road reserve or to present linear data graphically adjacent to the existing data.

Shifting a line sideways – ST_LineShift

A common and simple solution for moving a line parallel to itself is to extract the first and last vertex in a linestring, compute a single offset at right angles to an imaginary line composed of these vertexes, and then apply this to all the vertexes in the line. This is called line shifting and is implemented in ST_LineShift.

Create Or Replace Type T_Geometry As Object (
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