quit earlier after mutating a bend

This commit is contained in:
Motiejus Jakštys 2021-05-19 22:57:47 +03:00 committed by Motiejus Jakštys
parent 56c92b71d9
commit 523f00c8c9

15
wm.sql
View File

@ -254,17 +254,18 @@ declare
begin
mutated = false;
-- go through the bends and find one where sum of inflection angle is >180
<<bendloop>>
for i in 1..array_length(bends, 1) loop
continue when abs(inflection_angle(bends[i])) <= pi;
-- sum of inflection angles for this bend is >180, so it may be
-- self-crossing. now try to find another bend in this line that
-- crosses an imaginary line of end-vertices
-- go through each bend in the given line, and see if has a potential to
-- cross bends[i].
-- Go through each bend in the given line, and see if has a potential to
-- cross bends[i]. The line-cut process is different when i<j and i>j;
-- therefore there are two loops, one for each case.
for j in 1..i-1 loop
select if_selfcross(bends[i], bends[j]) into multi;
multi = if_selfcross(bends[i], bends[j]);
continue when multi is null;
mutated = true;
@ -278,11 +279,11 @@ begin
st_pointn(bends[i], st_npoints(bends[i]))
);
bends = bends[1:j] || bends[i+1:];
exit;
continue bendloop;
end loop;
for j in reverse array_length(bends, 1)..i+1 loop
select if_selfcross(bends[i], bends[j]) into multi;
multi = if_selfcross(bends[i], bends[j]);
continue when multi is null;
mutated = true;
@ -294,7 +295,7 @@ begin
st_removepoint(st_geometryn(multi, st_numgeometries(multi)), 0)
);
bends = bends[1:i] || bends[j+1:];
exit;
continue bendloop;
end loop;
end loop;
end