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Updated algorithm to split aoi when no linear features #31

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merged 10 commits into from
Jun 5, 2024
Merged

Updated algorithm to split aoi when no linear features #31

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a0b4ba6
refactor: updated algorithm to split aoi when no linear features, by …
Sujanadh May 21, 2024
d9216db
refactor: removed redundant sql
Sujanadh May 22, 2024
ae6e107
refactor: simplified the boundary of splitted ploygons and removed ha…
Sujanadh May 24, 2024
5c81b16
limit highways excluding small less important highways
Sujanadh May 27, 2024
12368bf
build: remove obsolete version key from docker-compose.yml
spwoodcock Jun 5, 2024
72da3af
ci: update all pre-commit hooks
spwoodcock Jun 5, 2024
83ef202
build: fix setting changes to ruff hook in pyproject
spwoodcock Jun 5, 2024
42b2dd4
ci: run pre-commit hooks on all
spwoodcock Jun 5, 2024
67b52d2
test: fix tests after sql algorithm updates
spwoodcock Jun 5, 2024
09dfcbf
[pre-commit.ci] auto fixes from pre-commit.com hooks
pre-commit-ci[bot] Jun 5, 2024
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208 changes: 142 additions & 66 deletions fmtm_splitter/fmtm_algorithm.sql
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Original file line number Diff line number Diff line change
@@ -1,67 +1,97 @@
DROP TABLE IF EXISTS polygonsnocount;
-- Create a new polygon layer of splits by lines

CREATE TABLE polygonsnocount AS (
-- The Area of Interest provided by the person creating the project
WITH aoi AS (
SELECT * FROM "project_aoi"
)
-- Extract all lines to be used as splitlines from a table of lines
-- with the schema from Underpass (all tags as jsonb column called 'tags')
-- TODO: add polygons (closed ways in OSM) with a 'highway' tag;
-- some features such as roundabouts appear as polygons.
-- TODO: add waterway polygons; now a beach doesn't show up as a splitline.
-- TODO: these tags should come from another table rather than hardcoded
-- so that they're easily configured during project creation.
,splitlines AS (
-- SELECT ST_Intersection(a.geom, l.geom) AS geom
-- FROM aoi a, "ways_line" l
-- WHERE ST_Intersects(a.geom, l.geom)
-- -- TODO: these tags should come from a config table
-- -- All highways, waterways, and railways
-- AND (l.tags->>'highway' IS NOT NULL
-- OR l.tags->>'waterway' IS NOT NULL
-- OR l.tags->>'railway' IS NOT NULL
-- )

SELECT * from lines_view l
WHERE l.tags->>'highway' IS NOT NULL
OR l.tags->>'waterway' IS NOT NULL
OR l.tags->>'railway' IS NOT NULL
DO $$
DECLARE
lines_count INTEGER;
num_buildings INTEGER;
BEGIN
-- Check if ways_line has any data
SELECT COUNT(*) INTO lines_count FROM ways_line;

IF lines_count > 0 THEN
CREATE TABLE polygonsnocount AS (

)
-- Merge all lines, necessary so that the polygonize function works later
,merged AS (
SELECT ST_LineMerge(ST_Union(splitlines.geom)) AS geom
FROM splitlines
)
-- Combine the boundary of the AOI with the splitlines
-- First extract the Area of Interest boundary as a line
,boundary AS (
SELECT ST_Boundary(geom) AS geom
FROM aoi
)
-- Then combine it with the splitlines
,comb AS (
SELECT ST_Union(boundary.geom, merged.geom) AS geom
FROM boundary, merged
)
-- TODO add closed ways from OSM to lines (roundabouts etc)
-- Create a polygon for each area enclosed by the splitlines
,splitpolysnoindex AS (
SELECT (ST_Dump(ST_Polygonize(comb.geom))).geom as geom
FROM comb
)
-- Add an index column to the split polygons
,splitpolygons AS(
SELECT
row_number () over () as polyid,
ST_Transform(spni.geom,4326)::geography AS geog,
spni.*
from splitpolysnoindex spni
)
SELECT * FROM splitpolygons
);
-- The Area of Interest provided by the person creating the project
WITH aoi AS (
SELECT * FROM "project_aoi"
)
-- Extract all lines to be used as splitlines from a table of lines
-- with the schema from Underpass (all tags as jsonb column called 'tags')
-- TODO: add polygons (closed ways in OSM) with a 'highway' tag;
-- some features such as roundabouts appear as polygons.
-- TODO: add waterway polygons; now a beach doesn't show up as a splitline.
-- TODO: these tags should come from another table rather than hardcoded
-- so that they're easily configured during project creation.
, splitlines AS (
SELECT ST_Intersection(a.geom, l.geom) AS geom
FROM aoi a
JOIN "ways_line" l ON ST_Intersects(a.geom, l.geom)
WHERE (
(l.tags->>'highway' IS NOT NULL AND
l.tags->>'highway' NOT IN ('unclassified', 'residential', 'service', 'pedestrian', 'track', 'bus_guideway')) -- TODO: update(add/remove) this based on the requirements later
OR l.tags->>'waterway' IS NOT NULL
OR l.tags->>'railway' IS NOT NULL
)
)

-- SELECT * from lines_view l
-- WHERE (
-- (l.tags->>'highway' IS NOT NULL AND
-- l.tags->>'highway' NOT IN ('unclassified', 'residential', 'service', 'pedestrian', 'track', 'bus_guideway'))
-- OR l.tags->>'waterway' IS NOT NULL
-- OR l.tags->>'railway' IS NOT NULL
-- )
-- )
-- Merge all lines, necessary so that the polygonize function works later
,merged AS (
SELECT ST_LineMerge(ST_Union(splitlines.geom)) AS geom
FROM splitlines
)
-- Combine the boundary of the AOI with the splitlines
-- First extract the Area of Interest boundary as a line
,boundary AS (
SELECT ST_Boundary(geom) AS geom
FROM aoi
)
-- Then combine it with the splitlines
,comb AS (
SELECT ST_Union(boundary.geom, merged.geom) AS geom
FROM boundary, merged
)
-- TODO add closed ways from OSM to lines (roundabouts etc)
-- Create a polygon for each area enclosed by the splitlines
,splitpolysnoindex AS (
SELECT (ST_Dump(ST_Polygonize(comb.geom))).geom as geom
FROM comb
)
-- Add an index column to the split polygons
,splitpolygons AS(
SELECT
row_number () over () as polyid,
ST_Transform(spni.geom,4326)::geography AS geog,
spni.*
from splitpolysnoindex spni
)
SELECT * FROM splitpolygons
);
ELSE
-- Calculate number of buildings per cluster
CREATE TABLE polygonsnocount AS (
WITH aoi AS (
SELECT * FROM "project_aoi"
)
,transformed_aoi AS(
SELECT
row_number () over () as polyid,
ST_Transform(aoi.geom,4326)::geography AS geog,
aoi.geom
from aoi
)
SELECT * FROM transformed_aoi
);
END IF;
END $$;


-- Make that index column a primary key
Expand Down Expand Up @@ -130,7 +160,7 @@ with lowfeaturecountpolys as (
select *
from splitpolygons as p
-- TODO: feature count should not be hard-coded
where p.numfeatures < 20
where p.numfeatures < %(num_buildings)s
),
-- Find the neighbors of the low-feature-count polygons
-- Store their ids as n_polyid, numfeatures as n_numfeatures, etc
Expand Down Expand Up @@ -258,15 +288,61 @@ USING GIST (geom);
-- VACUUM ANALYZE voronois;
DROP TABLE voronoids;

DROP TABLE IF EXISTS unsimplifiedtaskpolygons;
CREATE TABLE unsimplifiedtaskpolygons AS (
SELECT ST_Union(geom) as geom, clusteruid
FROM voronois
GROUP BY clusteruid
);

CREATE INDEX unsimplifiedtaskpolygons_idx
ON unsimplifiedtaskpolygons
USING GIST (geom);

--VACUUM ANALYZE unsimplifiedtaskpolygons;


--*****************************Simplify*******************************
-- Extract unique line segments
DROP TABLE IF EXISTS taskpolygons;
CREATE TABLE taskpolygons AS (
SELECT ST_Union(geom) as geom, clusteruid
FROM voronois
GROUP BY clusteruid
--Convert task polygon boundaries to linestrings
WITH rawlines AS (
SELECT utp.clusteruid, st_boundary(utp.geom) AS geom
FROM unsimplifiedtaskpolygons AS utp
)
-- Union, which eliminates duplicates from adjacent polygon boundaries
,unionlines AS (
SELECT st_union(l.geom) AS geom FROM rawlines l
)
-- Dump, which gives unique segments.
,segments AS (
SELECT (st_dump(l.geom)).geom AS geom
FROM unionlines l
)
,agglomerated AS (
SELECT st_linemerge(st_unaryunion(st_collect(s.geom))) AS geom
FROM segments s
)
,simplifiedlines AS (
SELECT st_simplify(a.geom, 0.000075) AS geom
FROM agglomerated a
)
,taskpolygonsnoindex as (
SELECT (st_dump(st_polygonize(s.geom))).geom AS geom
FROM simplifiedlines s
)
SELECT
row_number () over () as taskid,
tpni.*
FROM taskpolygonsnoindex tpni
);

-- ALTER TABLE taskpolygons ADD PRIMARY KEY(taskid);
SELECT Populate_Geometry_Columns('public.taskpolygons'::regclass);
CREATE INDEX taskpolygons_idx
ON taskpolygons
USING GIST (geom);
ON taskpolygons
USING GIST (geom);
-- VACUUM ANALYZE taskpolygons;


Expand Down
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