From d0972307e24afdddcf63049c8109a19568ac0052 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= <motiejus@uber.com>
Date: Tue, 6 Apr 2021 17:48:25 +0300
Subject: [PATCH] bend attrs

---
 IV/Makefile              | 13 +++++++------
 IV/tests-integration.sql | 10 +++++-----
 IV/wm.sql                | 35 ++++++++++++++++++++++++++++++-----
 3 files changed, 42 insertions(+), 16 deletions(-)

diff --git a/IV/Makefile b/IV/Makefile
index 312574b..6ba253e 100644
--- a/IV/Makefile
+++ b/IV/Makefile
@@ -1,5 +1,6 @@
 SOURCE ?= lithuania-latest.osm.pbf
-WHERE ?= name='Visinčia' OR name='Šalčia' OR name='Nemunas' OR name='Žeimena' OR name='Lakaja'
+#WHERE ?= name='Visinčia' OR name='Šalčia' OR name='Nemunas' OR name='Žeimena' OR name='Lakaja'
+WHERE ?= name='Žeimena' OR name='Lakaja'
 SLIDES = slides-2021-03-29.pdf
 
 NON_ARCHIVABLES = notes.txt referatui.txt slides-2021-03-29.txt
@@ -15,7 +16,7 @@ test-integration: .faux_filter-rivers
 .PHONY: clean
 clean:
 	-./db stop
-	-rm -r .faux_test .faux_filter-rivers .faux_import-osm .faux.db \
+	-rm -r .faux_test .faux_filter-rivers .faux_import-osm .faux_db \
 		version.tex test-figures.pdf _minted-mj-msc \
 		$(shell git ls-files -o mj-msc*) \
 		$(SLIDES)
@@ -45,22 +46,22 @@ mj-msc-full.pdf: mj-msc.pdf version.tex $(ARCHIVABLES)
 test-figures.pdf: layer2img.py .faux_test
 	python ./layer2img.py --group1-table=figures --group1-arrows=yes --outfile=$@
 
-.faux_test: tests.sql wm.sql .faux.db
+.faux_test: tests.sql wm.sql .faux_db
 	./db -f tests.sql
 	touch $@
 
-.faux_filter-rivers: .faux_import-osm
+.faux_filter-rivers: .faux_import-osm Makefile
 	./db -v where="$(WHERE)" -f aggregate-rivers.sql
 	touch $@
 
-.faux_import-osm: $(SOURCE) .faux.db
+.faux_import-osm: $(SOURCE) .faux_db
 	PGPASSWORD=osm osm2pgsql \
 			   -c --multi-geometry \
 			   -H 127.0.0.1 -d osm -U osm \
 			   $<
 	touch $@
 
-.faux.db:
+.faux_db:
 	./db start
 	touch $@
 
diff --git a/IV/tests-integration.sql b/IV/tests-integration.sql
index 0a0e2be..9f7a5ae 100644
--- a/IV/tests-integration.sql
+++ b/IV/tests-integration.sql
@@ -1,8 +1,8 @@
 \i wm.sql
 
-drop table if exists debug_wm;
-create table debug_wm(stage text, name text, gen bigint, nbend bigint, way geometry, props json);
+drop table if exists wm_debug;
+create table wm_debug(stage text, name text, gen bigint, nbend bigint, way geometry, props json);
 
-drop table if exists demo_wm;
-create table demo_wm (name text, i bigint, way geometry);
-insert into demo_wm (name, way) select name, ST_SimplifyWM(way, name) from agg_rivers;
+drop table if exists wm_demo;
+create table wm_demo (name text, i bigint, way geometry);
+insert into wm_demo (name, way) select name, ST_SimplifyWM(way, name) from agg_rivers;
diff --git a/IV/wm.sql b/IV/wm.sql
index 43fbee6..8f9dcf7 100644
--- a/IV/wm.sql
+++ b/IV/wm.sql
@@ -262,6 +262,7 @@ $$ language plpgsql;
 
 
 drop function if exists bend_attrs;
+drop function if exists isolated_bends;
 drop type if exists t_bend_attrs;
 create type t_bend_attrs as (
   bend geometry,
@@ -269,7 +270,8 @@ create type t_bend_attrs as (
   cmp real,
   adjsize real,
   baselinelength real,
-  avg_curvature real
+  curvature real,
+  isolated boolean
 );
 create function bend_attrs(bends geometry[], dbgname text default null) returns setof t_bend_attrs as $$
 declare
@@ -287,7 +289,8 @@ begin
     res.cmp = 0;
     res.adjsize = 0;
     res.baselinelength = st_distance(st_startpoint(bend), st_endpoint(bend));
-    res.avg_curvature = inflection_angle(bend) / st_length(bend);
+    res.curvature = inflection_angle(bend) / st_length(bend);
+    res.isolated = false;
     if st_numpoints(bend) >= 3 then
       polygon = st_makepolygon(st_addpoint(bend, st_startpoint(bend)));
       -- Compactness Index (cmp) is defined as "the ratio of the area of the
@@ -316,17 +319,37 @@ begin
           'cmp', res.cmp,
           'adjsize', res.adjsize,
           'baselinelength', res.baselinelength,
-          'avg_curvature', res.avg_curvature
+          'curvature', res.curvature
         )
       );
     end if;
-
     return next res;
-
   end loop;
 end;
 $$ language plpgsql;
 
+create function isolated_bends(INOUT bendattrs t_bend_attrs[], dbgname text default null) as $$
+declare
+  isolation_threshold constant real default 0.2; -- if neighbor's curvatures are within, it's isolated
+  this real;
+  res t_bend_attrs;
+  i int4;
+begin
+  i = 2;
+  while i < array_length(bendattrs, 1)-1 loop
+    this = bendattrs[i].curvature * isolation_threshold;
+    if bendattrs[i-1].curvature < this and bendattrs[i+1].curvature < this then
+      res = bendattrs[i];
+      res.isolated = true;
+      bendattrs[i] = res;
+      i = i + 2;
+    else
+      i = i + 1;
+    end if;
+  end loop;
+end
+$$ language plpgsql;
+
 -- ST_SimplifyWM simplifies a given geometry using Wang & Müller's
 -- "Line Generalization Based on Analysis of Shape Characteristics" algorithm,
 -- 1998.
@@ -338,6 +361,7 @@ declare
   line geometry;
   lines geometry[];
   bends geometry[];
+  bend_attrs t_bend_attrs[];
   mutated boolean;
   l_type text;
 begin
@@ -408,6 +432,7 @@ begin
 
       -- self-crossing mutations are done, calculate bend properties
       perform bend_attrs(bends, dbgname);
+
     end loop;
 
   end loop;