69 lines
2.0 KiB
PL/PgSQL
69 lines
2.0 KiB
PL/PgSQL
\i wm.sql
|
|
|
|
-- wm_envelope clips a geometry by a bounding box around a given object,
|
|
-- matching dimensions of A-class paper (1 by sqrt(2).
|
|
drop function if exists wm_bbox;
|
|
create function wm_bbox(
|
|
center geometry,
|
|
scaledwidth float
|
|
) returns geometry as $$
|
|
declare
|
|
halfX float;
|
|
halfY float;
|
|
begin
|
|
halfX = scaledwidth / 2;
|
|
halfY = halfX * sqrt(2);
|
|
return st_envelope(
|
|
st_union(
|
|
st_translate(center, halfX, halfY),
|
|
st_translate(center, -halfX, -halfY)
|
|
)
|
|
);
|
|
end
|
|
$$ language plpgsql;
|
|
|
|
delete from wm_visuals where name like 'salvis%';
|
|
insert into wm_visuals(name, way) values('salvis', (
|
|
select st_intersection(
|
|
(select st_union(way) from wm_rivers where name in ('Šalčia', 'Visinčia')),
|
|
wm_bbox(
|
|
st_closestpoint(
|
|
(select way from wm_rivers where name='Šalčia'),
|
|
(select way from wm_rivers where name='Visinčia')
|
|
),
|
|
:scaledwidth
|
|
)
|
|
)
|
|
));
|
|
|
|
do $$
|
|
declare
|
|
i integer;
|
|
geom1 geometry;
|
|
geom2 geometry;
|
|
begin
|
|
foreach i in array array[16, 64, 256] loop
|
|
geom1 = st_simplify((select way from wm_visuals where name='salvis'), i);
|
|
geom2 = st_simplifyvw((select way from wm_visuals where name='salvis'), i*i);
|
|
insert into wm_visuals(name, way) values
|
|
('salvis-douglas-' || i, geom1),
|
|
('salvis-douglas-' || i || '-chaikin', st_chaikinsmoothing(geom1, 5)),
|
|
('salvis-visvalingam-' || i, geom2),
|
|
('salvis-visvalingam-' || i || '-chaikin', st_chaikinsmoothing(geom2, 5));
|
|
end loop;
|
|
end $$ language plpgsql;
|
|
|
|
do $$
|
|
declare
|
|
npoints bigint;
|
|
secs bigint;
|
|
begin
|
|
select * from ST_SimplifyWM_Estimate((select st_union(way) from wm_rivers)) into npoints, secs;
|
|
raise notice 'Total points: %', npoints;
|
|
raise notice 'Expected duration: %s (+-%s)', ceil(secs), floor(secs*.5);
|
|
end $$ language plpgsql;
|
|
|
|
delete from wm_debug where name in (select distinct name from wm_rivers);
|
|
delete from wm_demo where name in (select distinct name from wm_rivers);
|
|
--insert into wm_demo (name, way) select name, ST_SimplifyWM(way, name) from wm_rivers;
|