From 44e5352c16924a1d347b4517d01f585ac4325412 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Motiejus=20Jak=C5=A1tys?= Date: Wed, 10 Mar 2021 15:56:08 +0200 Subject: [PATCH] formatting --- IV/wm.sql | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/IV/wm.sql b/IV/wm.sql index a6089da..ee5ba73 100644 --- a/IV/wm.sql +++ b/IV/wm.sql @@ -1,9 +1,9 @@ \set ON_ERROR_STOP on SET plpgsql.extra_errors TO 'all'; +-- detect_bends detects bends using the inflection angles. No corrections. drop function if exists detect_bends; --- detect_bends detects bends using the inflection angles. It does not do corrections. -create or replace function detect_bends(line geometry, OUT bends geometry[]) as $$ +create function detect_bends(line geometry, OUT bends geometry[]) as $$ declare pi real; p geometry; @@ -16,8 +16,8 @@ declare begin pi = radians(180); - -- the last vertex is iterated over twice, because the algorithm uses 3 vertices - -- to calculate the angle between them. + -- the last vertex is iterated over twice, because the algorithm uses 3 + -- vertices to calculate the angle between them. -- -- Given 3 vertices p1, p2, p3: -- @@ -97,7 +97,8 @@ $$ language plpgsql; -- fix_gentle_inflections1 fixes gentle inflections of an array of lines in -- one direction. This is an implementation detail of fix_gentle_inflections. -create or replace function fix_gentle_inflections1(INOUT bends geometry[]) as $$ +drop function if exists fix_gentle_inflections1; +create function fix_gentle_inflections1(INOUT bends geometry[]) as $$ declare pi real; small_angle real; @@ -145,13 +146,14 @@ begin -- if the bend got too short, stop processing it exit when array_length(phead, 1) < 3; - -- if inflection angle between ptail[1:3] "large", stop processing this bend + -- inflection angle between ptail[1:3] is "large", stop processing exit when abs(st_angle(phead[1], phead[2], phead[3]) - pi) > small_angle; - -- distance from head's first vertex should be larger than from second vertex + -- distance from head's 1st vertex should be larger than from 2nd vertex exit when st_distance(ptail, phead[2]) < st_distance(ptail, phead[3]); - -- detected a gentle inflection. Move head of the tail to the tail of head + -- Detected a gentle inflection. + -- Move head of the tail to the tail of head bends[i] = st_removepoint(bends[i], 0); bends[i-1] = st_addpoint(bends[i-1], phead[3]); end loop; @@ -162,7 +164,8 @@ $$ language plpgsql; -- self_crossing eliminates self-crossing from the bends, following the -- article's section "Self-line Crossing When Cutting a Bend". -create or replace function self_crossing(INOUT bends geometry[]) as $$ +drop function if exists self_crossing; +create function self_crossing(INOUT bends geometry[]) as $$ declare i int4; j int4; @@ -189,7 +192,9 @@ begin p1 = null; p2 = null; p3 = null; - for p0 in (select geom from st_dumppoints(bends[i]) order by path[1] asc) loop + for p0 in ( + select geom from st_dumppoints(bends[i]) order by path[1] asc + ) loop p3 = p2; p2 = p1; p1 = p0; @@ -219,8 +224,10 @@ begin -- are p2 and p3 on the different sides of line(p0,p1)? vector -- multiplication; https://stackoverflow.com/questions/1560492/ - s2 = (st_x(p0)-st_x(p1)*(st_y(p2)-st_y(p1))-(st_y(p0)-st_y(p1))*(st_x(p2)-st_x(p1))); - s3 = (st_x(p0)-st_x(p1)*(st_y(p3)-st_y(p1))-(st_y(p0)-st_y(p1))*(st_x(p3)-st_x(p1))); + s2 = (st_x(p0)-st_x(p1)*(st_y(p2)-st_y(p1))- + (st_y(p0)-st_y(p1))*(st_x(p2)-st_x(p1))); + s3 = (st_x(p0)-st_x(p1)*(st_y(p3)-st_y(p1))- + (st_y(p0)-st_y(p1))*(st_x(p3)-st_x(p1))); continue when sign(s2) = sign(s3); -- do end vertices of bend[i] cross bend[j]? @@ -228,12 +235,13 @@ begin b = st_pointn(bends[i], -1); multi = st_split(bends[j], st_makeline(a, b)); continue when st_numgeometries(multi) = 1; - continue when st_numgeometries(multi) = 2 and (st_contains(bends[j], a) or st_contains(bends[j], b)); + continue when st_numgeometries(multi) = 2 and + (st_contains(bends[j], a) or st_contains(bends[j], b)); -- real self-crossing detected! Remove it. -- if j < i: - -- bends[j] = multi[1][1...n-1]; that will have all the vertices of bends[j], - -- except the crossing and what comes after it. + -- bends[j] = multi[1][1...n-1]; that will have all the vertices of + -- bends[j], except the crossing and what comes after it. -- bends[j] = append(bends[j], bends[i][-1]) -- remove bends from bends[j+1] to bends[i] inclusive. -- j := i+1 @@ -253,7 +261,8 @@ begin prev_length = array_length(bends, 1); if j < i then bends[j] = st_geometryn(multi, 1); - bends[j] = st_setpoint(bends[j], st_npoints(bends[j])-1, st_pointn(bends[i], st_npoints(bends[i]))); + bends[j] = st_setpoint(bends[j], st_npoints(bends[j])-1, + st_pointn(bends[i], st_npoints(bends[i]))); bends = bends[1:j] || bends[i+1:prev_length]; j = i; else