double GDALGeometricAttributes::percentageFilled(OGRPolygon * ogr_poly) { char* geo; ogr_poly->exportToWkt(&geo); std::auto_ptr< SFCGAL::Geometry > g( SFCGAL::io::readWkt(geo)); SFCGAL::Polygon poly = g->as<SFCGAL::Polygon>(); if (!poly.toPolygon_2(false).is_simple()) { DM::Logger(DM::Warning) << "Polygon is not simple"; return -1; } //Transfer to GDAL polygon Polygon_with_holes_2 p = poly.toPolygon_with_holes_2(true); Polygon_2 p_c; CGAL::convex_hull_2(p.outer_boundary().vertices_begin(), p.outer_boundary().vertices_end(), std::back_inserter(p_c)); //Cacluate Minimal Rect Polygon_2 p_m; CGAL::min_rectangle_2(p_c.vertices_begin(), p_c.vertices_end(), std::back_inserter(p_m)); return ogr_poly->get_Area() / CGAL::to_double(p_m.area()); }
void OffsetWorker::run() { std::auto_ptr< SFCGAL::Geometry > g( SFCGAL::io::readWkt(wkt_poly)); OGRFree(wkt_poly); //Not needed after here switch ( g->geometryTypeId() ) { case SFCGAL::TYPE_POLYGON: break; default: return; } SFCGAL::Polygon poly = g->as<SFCGAL::Polygon>(); Polygon_2 p = poly.toPolygon_2(true); this->offsetPolygon(p, offset); }
double GDALGeometricAttributes::aspectRationBB(OGRPolygon * ogr_poly) { char* geo; ogr_poly->exportToWkt(&geo); std::auto_ptr< SFCGAL::Geometry > g( SFCGAL::io::readWkt(geo)); SFCGAL::Polygon poly = g->as<SFCGAL::Polygon>(); if (!poly.toPolygon_2(false).is_simple()) { DM::Logger(DM::Warning) << "Polygon is not simple"; return -1; } //Transfer to GDAL polygon Polygon_with_holes_2 p = poly.toPolygon_with_holes_2(true); Polygon_2 p_c; CGAL::convex_hull_2(p.outer_boundary().vertices_begin(), p.outer_boundary().vertices_end(), std::back_inserter(p_c)); //Cacluate Minimal Rect Polygon_2 p_m; CGAL::min_rectangle_2(p_c.vertices_begin(), p_c.vertices_end(), std::back_inserter(p_m)); Point_2 p1 = p_m.vertex(0); Point_2 p2 = p_m.vertex(1); Point_2 p3 = p_m.vertex(2); Point_2 p4 = p_m.vertex(3); Vector_2 v1 = (p2-p1); Vector_2 v2 = (p3-p2); double l1 = sqrt(CGAL::to_double(v1.squared_length())); double l2 = sqrt(CGAL::to_double(v2.squared_length())); double aspect_ration = l1/l2; if (aspect_ration < 1.0) { aspect_ration = 1.0/aspect_ration; } return aspect_ration; }