gis.road_graph

Parameters

Name	Type	Mode
_params	jsonb	IN

Definition

DECLARE
    -- Distance used by the triggers to split an edge by a node, and to reuse an existing node
    tolerance real = 0.50;
    cut_point geometry;
    node_id integer;
BEGIN
    cut_point = ST_GeomFromEWKT(_params->>'point');
    IF cut_point IS NULL THEN
        RETURN jsonb_build_object('status', 'error', 'message', 'The parameter point is missing');
    END IF;

-- The issue has already been fixed if no edge must be split at this point:
    -- no edge which can be cut passes there without starting or ending there
    IF NOT EXISTS (
        SELECT 1
        FROM road_graph.edges AS e
        WHERE ST_DWithin(e.geom, cut_point, tolerance)
        AND NOT ST_DWithin(ST_StartPoint(e.geom), cut_point, tolerance)
        AND NOT ST_DWithin(ST_EndPoint(e.geom), cut_point, tolerance)
        AND NOT Coalesce(e.no_intersection_cutting, False)
    ) THEN
        RETURN jsonb_build_object('status', 'skipped', 'message', 'No edge to split at this point');
    END IF;

-- Use the existing node close to the cut_point, if any: touching it splits the edges under it
    SELECT n.id
    INTO node_id
    FROM road_graph.nodes AS n
    WHERE ST_DWithin(n.geom, cut_point, tolerance)
    ORDER BY n.geom <-> cut_point
    LIMIT 1
    ;
    IF node_id IS NOT NULL THEN
        SET LOCAL road.graph.edge.update.touching.node = 'yes';
        UPDATE road_graph.nodes AS n
        SET geom = n.geom
        WHERE n.id = node_id
        ;
        SET LOCAL road.graph.edge.update.touching.node = 'no';
        RETURN jsonb_build_object(
            'status', 'success',
            'message', format('The edges have been split by the existing node %s', node_id)
        );
    END IF;

-- Create a node at the point: the triggers split the edges under it
    INSERT INTO road_graph.nodes (geom)
    VALUES (cut_point)
    RETURNING id INTO node_id
    ;

RETURN jsonb_build_object(
        'status', 'success',
        'message', format('The edges have been split by the new node %s', node_id)
    );
END;

fix_graph_cut_edges(_params jsonb)

Description

Parameters

Definition