wm

Wang–Müller line generalization algorithm in PostGIS
Log | Files | Refs | README | LICENSE

test.sql (9586B) - Raw


      1 \i wm.sql
      2 
      3 -- https://stackoverflow.com/questions/19982373/which-tools-libraries-do-you-use-to-unit-test-your-pl-pgsql
      4 create or replace function assert_equals(expected anyelement, actual anyelement) returns void as $$
      5 begin
      6   if expected = actual or (expected is null and actual is null) then
      7     --do nothing
      8   else
      9     raise exception 'Assertion Error. Expected <%> but was <%>', expected, actual;
     10   end if;
     11 end $$ language plpgsql;
     12 
     13 drop function if exists dbg_geomsummary;
     14 create function dbg_geomsummary(geoms geometry[]) returns void as $$
     15   declare i int4;
     16 begin
     17   raise notice 'len: %', array_length(geoms, 1);
     18   for i in 1..array_length(geoms, 1) loop
     19     raise notice '% %: %', st_geometrytype(geoms[i]), lpad(i::text, 2, '0'), st_astext(geoms[i]);
     20   end loop;
     21 end
     22 $$ language plpgsql;
     23 
     24 drop table if exists wm_figures;
     25 create table wm_figures (name text, way geometry);
     26 -- add fig8.gpkg to postgis:
     27 --   ogr2ogr -update -f PostgreSQL PG:"host=127.0.0.1 user=osm password=osm dbname=osm" fig8.gpkg
     28 -- to "normalize" a new line when it's in `f`:
     29 --   select st_astext(st_snaptogrid(st_transscale(geometry, -19.5, .016, 4000, 4000), 1)) from f;
     30 insert into wm_figures (name, way) values
     31   ('fig3',          'LINESTRING(0 0,12 0,13 4,20 2,20 0,32 0,33 10,38 16,43 15,44 10,44 0,60 0)'::geometry),
     32   ('fig3-1',        'LINESTRING(0 0,12 0,13 4,20 2,20 0,32 0,33 10,38 16,43 15,44 10,44 0)'::geometry),
     33   ('fig5',          'LINESTRING(0 39,19 52,27 77,26 104,41 115,49 115,65 103,65 75,53 45,63 15,91 0)'::geometry),
     34   ('fig6',          'LINESTRING(84 47,91 59,114 64,122 80,116 92,110 93,106 106,117 118,136 107,135 76,120 45,125 39,141 39,147 32)'::geometry),
     35   ('fig8',          'LINESTRING(173 12,174 10,180 8,186 8,186 13,191 11,189 6,201 5,203 11,216 16,216 6,222 6,229 3,236 2,239 6,243 8,248 6)'::geometry),
     36   ('inflection-1',  'LINESTRING(110 24,114 20,133 20,145 15,145 0,136 8,123 10,114 10,111 2)'::geometry),
     37   ('multi-island',  'MULTILINESTRING((-15 10,-10 10,-5 11,0 11,5 11,10 10,11 9,13 10,15 9),(-5 11,-2 15,0 16,2 15,5 11))'::geometry),
     38   ('selfcrossing-1','LINESTRING(-27 180,-20 166,-21 142,-18 136,55 136,55 136,71 145,44 165,37 146,22 145,14 164,11 164,3 146,-12 146,-13 176,-18 184)'::geometry),
     39   ('isolated-1',    'LINESTRING(-50 103,-48 102,-30 103,-31 105,-31 107,-27 107,-26 103,-6 103,-4 104)'::geometry),
     40   ('isolated-2',    'LINESTRING(250 100,246 104,234 105,230 106,225 101,224 93,217 78,206 69)'::geometry);
     41 
     42 insert into wm_figures (name, way) values ('fig6-rev',ST_Reverse(
     43     ST_Translate((select way from wm_figures where name='fig6'), 60, 0)));
     44 insert into wm_figures (name, way) values ('fig6-combi', ST_Union(
     45       ST_Translate((select way from wm_figures where name='fig6'), 0, 90),
     46       ST_Translate((select way from wm_figures where name='fig6'), 80, 90)
     47   ));
     48 
     49 insert into wm_figures (name, way) values ('selfcrossing-1-rev',ST_Reverse(
     50     ST_Translate((select way from wm_figures where name='selfcrossing-1'), 0, 60)));
     51 
     52 -- 3395 is now "reserved" for figures.
     53 update wm_figures set way=st_setsrid(way, 3395);
     54 
     55 delete from wm_debug where name in (select distinct name from wm_figures);
     56 delete from wm_demo where name in (select distinct name from wm_figures);
     57 insert into wm_demo (name, way) select name, ST_SimplifyWM(way, .1, null, name) from wm_figures where name not in ('fig8', 'isolated-1');
     58 insert into wm_demo (name, way) select name, ST_SimplifyWM(way, 14, null, name) from wm_figures where name in ('fig8', 'isolated-1', 'isolated-2');
     59 
     60 drop function if exists wm_debug_get;
     61 create function wm_debug_get( _stage text, _name text, OUT ways geometry[]) as $$
     62 declare
     63 begin
     64   ways = array((select way from wm_debug where stage=_stage and name=_name order by id));
     65 end $$ language plpgsql;
     66 
     67 do $$
     68 declare
     69   vbends geometry[];
     70 begin
     71   vbends = wm_debug_get('bbends', 'fig3');
     72   perform assert_equals(5, array_length(vbends, 1));
     73   perform assert_equals('LINESTRING(0 0,12 0,13 4)', st_astext(vbends[1]));
     74   perform assert_equals('LINESTRING(12 0,13 4,20 2,20 0)', st_astext(vbends[2]));
     75   perform assert_equals('LINESTRING(20 2,20 0,32 0,33 10)', st_astext(vbends[3]));
     76   perform assert_equals('LINESTRING(32 0,33 10,38 16,43 15,44 10,44 0)', st_astext(vbends[4]));
     77   perform assert_equals(4, array_length(wm_detect_bends((select way from wm_figures where name='fig3-1')), 1));
     78   select wm_detect_bends((select way from wm_figures where name='fig5')) into vbends;
     79   perform assert_equals(3, array_length(vbends, 1));
     80 end $$ language plpgsql;
     81 
     82 do $$
     83 declare
     84   vbends geometry[];
     85   vinflections geometry[];
     86 begin
     87   vinflections = wm_debug_get('cinflections', 'fig5');
     88   perform assert_equals('LINESTRING(0 39,19 52,27 77)', st_astext(vinflections[1]));
     89   perform assert_equals('LINESTRING(19 52,27 77,26 104,41 115,49 115,65 103,65 75,53 45)', st_astext(vinflections[2]));
     90   perform assert_equals('LINESTRING(65 75,53 45,63 15,91 0)', st_astext(vinflections[3]));
     91 
     92   -- inflections-1, the example in fix_gentle_inflections docstring
     93   select array((select way from wm_debug where name='inflection-1' and stage='bbends')) into vbends;
     94   select array((select way from wm_debug where name='inflection-1' and stage='cinflections')) into vinflections;
     95   perform assert_equals(vbends[1], vinflections[1]); -- unchanged
     96   perform assert_equals('LINESTRING(114 20,133 20,145 15,145 0,136 8,123 10,114 10)', st_astext(vinflections[2]));
     97   perform assert_equals('LINESTRING(123 10,114 10,111 2)', st_astext(vinflections[3]));
     98 end $$ language plpgsql;
     99 
    100 do $$
    101 declare
    102   fig6 constant text default 'LINESTRING(84 47,91 59,114 64,120 45,125 39,141 39,147 32)';
    103   selfcrossing1 constant text default 'LINESTRING(-27 180,-20 166,-13 176,-18 184)';
    104   vcrossings geometry[];
    105   mutated boolean;
    106 begin
    107   select * from wm_self_crossing(wm_debug_get('cinflections', 'fig6')) into vcrossings, mutated;
    108   perform assert_equals(true, mutated);
    109   perform assert_equals(
    110     fig6,
    111     (select st_astext(
    112         st_linemerge(st_union(way))
    113     ) from (select unnest(vcrossings) way) a)
    114   );
    115 
    116   select * from wm_self_crossing(wm_debug_get('cinflections', 'fig6-rev')) into vcrossings, mutated;
    117   perform assert_equals(true, mutated);
    118   perform assert_equals(
    119     fig6,
    120     (select st_astext(
    121         st_translate(st_reverse(st_linemerge(st_union(way))), -60, 0)
    122     ) from (select unnest(vcrossings) way) a)
    123   );
    124 
    125   select * from wm_self_crossing(wm_debug_get('cinflections', 'fig6-combi')) into vcrossings, mutated;
    126   perform assert_equals(true, mutated);
    127   perform assert_equals(
    128     'MULTILINESTRING((84 137,91 149,114 154,120 135,125 129,141 129,147 122),(164 137,171 149,194 154,200 135,205 129,221 129,227 122))',
    129     (select st_astext(
    130         st_linemerge(st_union(way))
    131     ) from (select unnest(vcrossings) way) a)
    132   );
    133 
    134 
    135   select * from wm_self_crossing(wm_debug_get('cinflections', 'selfcrossing-1')) into vcrossings, mutated;
    136   perform assert_equals(true, mutated);
    137   perform assert_equals(
    138     selfcrossing1,
    139     (select st_astext(
    140         st_linemerge(st_union(way))
    141     ) from (select unnest(vcrossings) way) a)
    142   );
    143 
    144   select * from wm_self_crossing(wm_debug_get('cinflections', 'selfcrossing-1-rev')) into vcrossings, mutated;
    145   perform assert_equals(true, mutated);
    146   perform assert_equals(
    147     selfcrossing1,
    148     (select st_astext(
    149         st_translate(st_reverse(st_linemerge(st_union(way))), 0, -60)
    150     ) from (select unnest(vcrossings) way) a)
    151   );
    152 
    153 end $$ language plpgsql;
    154 
    155 -- verifying bends in fig8 are eliminated like explained in the WM paper
    156 do $$
    157 declare
    158   fig8gen2 constant text default 'LINESTRING(173 12,174 10,180 8,186 8,189 6,201 5,203 11,216 16,216 6,229 3,236 2,239 6,243 8,248 6)';
    159   fig8gen3 constant text default 'LINESTRING(173 12,174 10,180 8,189 6,201 5,203 11,216 16,216 6,229 3,236 2,239 6,243 8,248 6)';
    160   eliminations geometry[];
    161 begin
    162   eliminations = wm_debug_get('afigures', 'fig8');
    163   perform assert_equals(fig8gen2, st_astext(eliminations[2]));
    164   perform assert_equals(fig8gen3, st_astext(eliminations[3]));
    165 end $$ language plpgsql;
    166 
    167 -- testing wm_exaggerate_bend2 in isolation
    168 do $$
    169 declare
    170   fig3b2 geometry;
    171   bend geometry;
    172   size float;
    173 begin
    174   select way from wm_debug where name='fig3' and stage='bbends' and gen=1 and nbend=2 into fig3b2;
    175   size = wm_adjsize(fig3b2);
    176   bend = wm_exaggerate_bend2(fig3b2, size, 50.);
    177   perform assert_equals('ST_LineString', st_geometrytype(bend));
    178   insert into wm_debug(stage, name, gen, nbend, way) values('manual', 'fig3', 1, 1, bend);
    179 end $$ language plpgsql;
    180 
    181 -- misc visuals
    182 do $$
    183   declare fig6b1 geometry;
    184   declare fig6b2 geometry;
    185   declare sclong geometry;
    186   declare scshort geometry;
    187 begin
    188   select way from wm_debug where name='fig6' and stage='bbends' and gen=1 into fig6b1 limit 1 offset 0;
    189   select way from wm_debug where name='fig6' and stage='bbends' and gen=1 into fig6b2 limit 1 offset 2;
    190   insert into wm_visuals (name, way) values('fig6-baseline', st_makeline(st_startpoint(fig6b2), st_endpoint(fig6b2)));
    191   insert into wm_visuals (name, way) values('fig6-newline', st_makeline(st_endpoint(fig6b1), st_endpoint(fig6b2)));
    192 
    193   select way from wm_debug where name='selfcrossing-1' and stage='bbends' and gen=1 into sclong limit 1 offset 1;
    194   select way from wm_debug where name='selfcrossing-1' and stage='bbends' and gen=1 into scshort limit 1 offset 4;
    195   insert into wm_visuals (name, way) values('selfcrossing-1-baseline', st_makeline(st_startpoint(sclong), st_endpoint(sclong)));
    196   insert into wm_visuals (name, way) values('selfcrossing-1-newline', st_makeline(st_startpoint(sclong), st_endpoint(scshort)));
    197 end $$ language plpgsql;
    198