[Boost-bugs] [Boost C++ Libraries] #12197: is_valid returns self-intersection error for multipolygons with many decimal

Subject: [Boost-bugs] [Boost C++ Libraries] #12197: is_valid returns self-intersection error for multipolygons with many decimal
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-05-12 21:10:49

#12197: is_valid returns self-intersection error for multipolygons with many
decimal
--------------------------------------+------------------------------
 Reporter:  jean.sebastien.carrier@…  |       Type:  Bugs
   Status:  new                       |  Milestone:  To Be Determined
Component:  None                      |    Version:  Boost 1.59.0
 Severity:  Problem                   |   Keywords:
--------------------------------------+------------------------------
 The following code:

 {{{
 typedef boost::geometry::model::polygon<Point> Polygon;
 typedef boost::geometry::model::multi_polygon<Polygon> MultiPolygon;

 Polygon outer1{ {
    { 2753.82399, 22518.895 },
    { 2790.93453, 22448.2618 },
    { 14793.2302, 27809.5376 },
    { 14590.7789, 28141.4075 },
    { 16120.2042, 25634.299 },
    { 16830.1157, 23682.3504 },
    { 3698, 17280.4245 },
    { 3698, 20053 },
    { 3290.86756, 20924.5835 },
    { 3140.68998, 21523.9236 },
    { 2753.82399, 22518.895 }
 } };

 Polygon outer2{ {
    { -4891.23816, 18463.1873 },
    { -5184.20528, 17101.1945 },
    { -5793.67689, 15410.9396 },
    { -6670.90183, 13924.6072 },
    { -7655.52041, 12671.2939 },
    { -8707.48466, 11854.286 },
    { -9810.20847, 11342.7777 },
    { -11002.6639, 11255.3896 },
    { -12121.6054, 11341.764 },
    { -13226.5153, 11854.286 },
    { -14278.4796, 12671.2939 },
    { -14967.9231, 13548.8837 },
    { -4891.23816, 18463.1873 }
 } };

 Polygon outer3{ {
    { -15799.8356, 25348.5883 },
    { -15939.2155, 25634.3426 },
    { -14410.8012, 28141.3084 },
    { -12165.7175, 30390.1272 },
    { -9561.60646, 32349.5454 },
    { -6622.17286, 33700.601 },
    { -3329.74574, 34602.3629 },
    { -0.657491358, 34754.8041 },
    { 3511.98218, 34602.0035 },
    { 3199.23919, 34615.6034 },
    { -15799.8356, 25348.5883 }
 } };

 MultiPolygon multiPolygon;
 multiPolygon.push_back(outer1);
 multiPolygon.push_back(outer2);
 multiPolygon.push_back(outer3);

 std::cout << (boost::geometry::is_valid(outer1) ? "outer1 is valid" :
 "outer1 is invalid") << std::endl;
 std::cout << (boost::geometry::is_valid(outer2) ? "outer2 is valid" :
 "outer2 is invalid") << std::endl;
 std::cout << (boost::geometry::is_valid(outer3) ? "outer3 is valid" :
 "outer3 is invalid") << std::endl;
 std::cout << (boost::geometry::intersects(outer1, outer2) ? "1 and 2
 intersects" : "1 and 2 do not intersects") << std::endl;
 std::cout << (boost::geometry::intersects(outer1, outer3) ? "1 and 3
 intersects" : "1 and 3 do not intersects") << std::endl;
 std::cout << (boost::geometry::intersects(outer3, outer2) ? "3 and 2
 intersects" : "3 and 2 do not intersects") << std::endl;
 boost::geometry::validity_failure_type failure;
 auto test = boost::geometry::is_valid(multiPolygon, failure);
 std::cout << (test ? "multiPolygon is valid " : "multiPolygon is invalid
 ") << failure << std::endl;
 }}}

 will fail (and show error code 21), but keep the same values, shorten
 every number by a few decimals, and all of a sudden, is_valid starts
 working again

 {{{
 typedef boost::geometry::model::polygon<Point> Polygon;
 typedef boost::geometry::model::multi_polygon<Polygon> MultiPolygon;

 Polygon outer1{ {
 {2753.82, 22518.9},
 {2790.93, 22448.3},
 {14793.2, 27809.5},
 {14590.8, 28141.4},
 {16120.2, 25634.3},
 {16830.1, 23682.4},
 {3698, 17280.4}   ,
 {3698, 20053}     ,
 {3290.87, 20924.6},
 {3140.69, 21523.9},
 {2753.82, 22518.9}
 } };

 Polygon outer2{ {
 {-4891.24, 18463.2},
 {-5184.21, 17101.2},
 {-5793.68, 15410.9},
 {-6670.9, 13924.6} ,
 {-7655.52, 12671.3},
 {-8707.48, 11854.3},
 {-9810.21, 11342.8},
 {-11002.7, 11255.4},
 {-12121.6, 11341.8},
 {-13226.5, 11854.3},
 {-14278.5, 12671.3},
 {-14967.9, 13548.9},
 {-4891.24, 18463.2}
 } };

 Polygon outer3{ {
 {-15799.8, 25348.6},
 {-15939.2, 25634.3},
 {-14410.8, 28141.3},
 {-12165.7, 30390.1},
 {-9561.61, 32349.5},
 {-6622.17, 33700.6},
 {-3329.75, 34602.4},
 {-0.657491, 34754.8},
 {3511.98, 34602},
 {3199.24, 34615.6},
 {-15799.8, 25348.6}
 } };

 MultiPolygon multiPolygon;
 multiPolygon.push_back(outer1);
 multiPolygon.push_back(outer2);
 multiPolygon.push_back(outer3);

 std::cout << (boost::geometry::is_valid(outer1) ? "1 is valid" : "1 is
 invalid") << std::endl;
 std::cout << (boost::geometry::is_valid(outer2) ? "2 is valid" : "2 is
 invalid") << std::endl;
 std::cout << (boost::geometry::is_valid(outer3) ? "3 is valid" : "3 is
 invalid") << std::endl;
 std::cout << (boost::geometry::intersects(outer1, outer2) ? "1 and 2
 intersects" : "1 and 2 do not intersects") << std::endl;
 std::cout << (boost::geometry::intersects(outer1, outer3) ? "1 and 3
 intersects" : "1 and 3 do not intersects") << std::endl;
 std::cout << (boost::geometry::intersects(outer3, outer2) ? "3 and 2
 intersects" : "3 and 2 do not intersects") << std::endl;
 std::cout << (boost::geometry::is_valid(multiPolygon) ? "multiPolygon is
 valid" : "multiPolygon is invalid") << std::endl;
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12197>
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