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16
IV/wm.sql
16
IV/wm.sql
@ -23,20 +23,20 @@ begin
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--
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-- p1___ ...
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-- /
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-- ..._____/
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-- ... _____/
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-- p3 p2
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--
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-- This loop will use p1 as the head vertex, p2 will be the measured angle,
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-- and p3 will be trailing. The line that will be added to the bend will
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-- always be [p3,p2].
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-- When looping over the line, p1 will be head (lead) vertex, p2 will be the
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-- measured angle, and p3 will be trailing. The line that will be added to
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-- the bend will always be [p3,p2].
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-- So once the p1 becomes the last vertex, the loop terminates, and the
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-- [p2,p1] line will not have a chance to be added. So the loop adds the last
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-- vertex twice, so it has a chance to become p2, and be added to the bend.
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--
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for p in (
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(select (dp).geom from st_dumppoints(line) as dp order by (dp).path[1] asc)
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(select geom from st_dumppoints(line) order by path[1] asc)
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union all
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(select (dp).geom from st_dumppoints(line) as dp order by (dp).path[1] desc limit 1)
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(select geom from st_dumppoints(line) order by path[1] desc limit 1)
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) loop
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p3 = p2;
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p2 = p1;
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@ -61,8 +61,8 @@ begin
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prev_sign = cur_sign;
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end loop;
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-- the last bend may be lost if there is no "final" inflection angle. Add it.
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if (select count(1) from ((select st_dumppoints(bend) as a)) b) >= 2 then
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-- the last line may be lost if there is no "final" inflection angle. Add it.
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if (select count(1) >= 2 from st_dumppoints(bend)) then
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bends = bends || bend;
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end if;
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end
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