Ticket #1747 (new enhancement)
Allow calibrating a linestring from a collection of PointM
|Reported by:||amaneiro||Owned by:||pramsey|
Description (last modified by pramsey) (diff)
Nowadays, postgis allow calibrating a linestring with ST_AddMeasure. Although very useful, it is not enough to cover some common cases when calibrating lines: for example, in road management is very usual that the ratio between a route's length and its measures is not constant. It's typical to have a table with measured points (mileage points, for example) and use it to calibrate the linestring.
So, a method to calibrate a linestring from a collection of PointM would be very helpful. Something like ... ?
geometry ST_AddMeasure(geometry geom_mline, geometry points_collection);
To take into account:
* the measured points not intersect with the line: the user should be able to set a offset/buffer for the points to be snapped to linestring. Somethink like ... ?
geometry ST_AddMeasure(geometry geom_mline, geometry points_collection, float buffer);
* start & end points of linestring: sometimes, the collection of measured points provided might not to be the start or end points of the linestring. I see two actions could be taken to prevent this: 1) require the user to provide a collection where the points match up to the ones on linestring or 2) allow the user to set measures for start & end points of linestring. Something like... ?
geometry ST_AddMeasure(geometry geom_mline, geometry points_collection, float start_measure, float end_measure);
* See this thread for more info.