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CREATE TYPE axh_linestring_to_points AS (geom GEOMETRY, when_at TIMESTAMP);
-- Input is a
-- * linestring geometry
-- * start timestamp
-- * end timestamp
-- * frequency integer (number of seconds between each point
-- Run it, SELECT (axh_linetime_to_points(the_geom, starttime, stoptime, 20)).* from andrew_20_281_29 WHERE cartodb_id = 581
CREATE OR REPLACE FUNCTION axh_linetime_to_points(input GEOMETRY, start TIMESTAMP WITH TIME ZONE, endt TIMESTAMP WITH TIME ZONE, frequency NUMERIC)
RETURNS SETOF axh_linestring_to_points AS $$
DECLARE
rettype axh_linestring_to_points%ROWTYPE;
ret GEOMETRY;
units INT;
counter INT := 1;
BEGIN
input := ST_GeometryN(input, 1);
units := floor(extract(EPOCH FROM (endt - start))::numeric / frequency);
FOR rettype IN SELECT ST_PointN(input, 1), start LOOP
RETURN NEXT rettype;
END LOOP;
WHILE counter <= units LOOP
FOR rettype IN SELECT ST_Line_Interpolate_Point(input, counter/units::numeric), start + INTERVAL '1 seconds' * frequency * counter LOOP
RETURN NEXT rettype;
END LOOP;
counter := counter +1;
END LOOP;
FOR rettype IN SELECT ST_PointN(ST_Reverse(input), 1), endt LOOP
RETURN NEXT rettype;
END LOOP;
RETURN;
END
$$ language plpgsql;
CREATE OR REPLACE FUNCTION axh_blend_lines(input GEOMETRY)
RETURNS GEOMETRY AS $$
DECLARE
-- sql TEXT;
first GEOMETRY;
next GEOMETRY;
back GEOMETRY;
last GEOMETRY;
invert GEOMETRY;
linestring GEOMETRY;
backstring GEOMETRY;
-- mem GEOMETRY;
nearest GEOMETRY;
closest GEOMETRY;
-- start BOOLEAN := TRUE;
ret axh_miles_test_ret%rowtype;
ret_id INT[];
ret_geom GEOMETRY[];
ret_line GEOMETRY[];
size INT;
curr INT;
top GEOMETRY[];
bot GEOMETRY[];
-- allret axh_miles_test_ret%rowtype[];
--CREATE TYPE axh_miles_test_ret AS (i INT, id INT, geom GEOMETRY, line GEOMETRY);
BEGIN
first := ST_PointN(input, 1);
last := ST_PointN(ST_Reverse(input), 1);
SELECT INTO nearest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), first)) FROM new_york_osm_line_clean WHERE z_order > 2 AND the_geom IS NOT NULL ORDER BY the_geom <-> first LIMIT 1;
-- top := top || first;
select into top array_agg(i) from (values (first), (nearest)) n(i);
-- top := top || nearest;
-- init our linestring, we'll skip the first array point later
linestring := ST_MakeLine(first, nearest);
-- DO IT BACKWARDS
invert = ST_Reverse(input);
SELECT INTO closest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), last)) FROM new_york_osm_line_clean WHERE z_order > 2 AND the_geom IS NOT NULL ORDER BY the_geom <-> last LIMIT 1;
select into bot array_agg(i) from (values (last), (closest)) n(i);
backstring := ST_MakeLine(last, closest);
size := 200;
curr := 1;
WHILE curr <= size LOOP
-- Do it from the top
-- first := top[1:array_upper(top, 1) - 1];
first := ST_Line_Interpolate_Point(ST_MakeLine(nearest, last), (curr+0.0)/(2.0*size+1.0));
IF curr <(size/4) THEN
SELECT INTO nearest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), first)) FROM new_york_osm_line_clean WHERE z_order > 2 AND the_geom IS NOT NULL ORDER BY the_geom <-> first LIMIT 1;
ELSE
SELECT INTO nearest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), first)) FROM new_york_osm_line_clean WHERE z_order > 3 AND the_geom IS NOT NULL ORDER BY the_geom <-> first LIMIT 1;
END IF;
-- linestring = ST_AddPoint(linestring, nearest);
-- top := array_append(top, nearest);
linestring = ST_AddPoint(linestring, nearest);
curr := curr + 1;
END LOOP;
curr := 1;
WHILE curr <= size LOOP
-- And reverse from the bottom
last = ST_Line_Interpolate_Point(ST_MakeLine(closest, first), (curr+0.0)/(2.0*size+1.0));
IF curr <(size/4) THEN
SELECT INTO closest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), last)) FROM new_york_osm_line_clean WHERE z_order > 2 AND the_geom IS NOT NULL ORDER BY the_geom <-> last LIMIT 1;
ELSE
SELECT INTO closest line_interpolate_point(ST_GeometryN(the_geom,1), line_locate_point(ST_GeometryN(the_geom,1), last)) FROM new_york_osm_line_clean WHERE z_order > 3 AND the_geom IS NOT NULL ORDER BY the_geom <-> last LIMIT 1;
END IF;
backstring = ST_AddPoint(backstring, closest);
bot := array_append(bot, closest);
curr := curr + 1;
END LOOP;
-- linestring = ST_LineMerge(ST_Collect(linestring, ST_Reverse(backstring)));
curr := array_upper(bot, 1);
WHILE curr > 0 LOOP
linestring = ST_AddPoint(linestring, bot[curr]);
curr := curr - 1;
END LOOP;
RETURN linestring;
END
$$ language plpgsql;
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