Re: [Boost-bugs] [Boost C++ Libraries] #10961: Wrong turns generated by get_turns() for Linear spikes. (was: Wrong turns generated by get_turns() for a Linear spikes.)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10961: Wrong turns generated by get_turns() for Linear spikes. (was: Wrong turns generated by get_turns() for a Linear spikes.)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-02-03 17:58:25

#10961: Wrong turns generated by get_turns() for Linear spikes.
---------------------------+----------------------------------------
  Reporter:  awulkiew      |      Owner:  awulkiew
      Type:  Bugs          |     Status:  closed
 Milestone:  Boost 1.58.0  |  Component:  geometry
   Version:  Boost 1.57.0  |   Severity:  Problem
Resolution:  fixed         |   Keywords:  overlay, relate, get_turns
---------------------------+----------------------------------------
Description changed by awulkiew:

Old description:

> 1. For L/A:
> {{{
> "LINESTRING(7 8, 6 10, 10 2)"
> "POLYGON((0 0,0 10,10 10,10 0,0 0))"
>
> "LINESTRING(7 8, 6 10, 11 0)"
> "POLYGON((0 0,0 10,10 10,10 0,0 0))"
> }}}
> for intersection point `(6 10)` u/u is generated instead of i/u.
>
> 2. For L/L:
> {{{
> "LINESTRING(6 0,0 0,5 0)"
> "LINESTRING(2 0,0 0,-10 0)"
> }}}
> for intersection point `(0 0)` only one, wrong turn is generated (a spike
> is not detected as a spike).

New description:

 1. For L/A:
 {{{
 "LINESTRING(7 8, 6 10, 10 2)"
 "POLYGON((0 0,0 10,10 10,10 0,0 0))"

 "LINESTRING(7 8, 6 10, 11 0)"
 "POLYGON((0 0,0 10,10 10,10 0,0 0))"
 }}}
 for intersection point `(6 10)` u/u is generated instead of i/u.

 2. For L/L:
 {{{
 "LINESTRING(6 0,0 0,5 0)"
 "LINESTRING(2 0,0 0,-10 0)"
 }}}
 for intersection point `(0 0)` only one, wrong turn is generated (a spike
 is not detected as a spike).

 3. For L/L
 {{{
 "LINESTRING(-7 -8,3 0,4 -1,-7 10)"
 "LINESTRING(-5 -4,3 0,4 -1,7 -4,2 -1)"
 }}}
 similar to the above.

--
-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10961#comment:4>
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