Hi all, I did a small investigation of the polygon-related segfaults/miscalculations. It looks like Boost.polygon badly handles cases where intersection points of the edges of the polygons lie close to each other or overlap, causing the 'snap rounding' algorithm used in boost to go haywire. This is the case for complex zones, with a lot of thermal holes or via patterns (i.e. a thermal pad under a QFN with a via field).
See last comment from https://svn.boost.org/trac/boost/ticket/10642. There's a variety of effects I observed. - a segfault. - an incorrect or empty resulting polygon: merging the holes before subtraction from the main outline (polyset_holes in AddClearanceAreasPolygonsToPolysList) using boost::assign or subtracting the holes one-by-one (instead of the whole set) fixes the segfault, but I know at least one case where the resulting zone is incorrectly calculated. I'll attach the test cases to the bug report on Launchpad later in the evening. For the reasons above, I would strongly consider dropping boost::polygon. There are also non-technical issues: - It hasn't been maintained for ~1.5 years. The last activity of the official maintainer was 3 years ago. - the code is a mess (look at example below). @Jean Pierre: do you think Clipper is stable enough for our use? (at least in case of a bug, it's actively developed and the author offers support). I'm not asking about speed, it's not important if Kicad crashes or produces incorrect polygons. Tom -- snip -- if(solid) { //we are closing a solid figure, write to output //std::cout << "test1\n"; at1->copyHoles(*(at1->otherTailp_)); typename PolyLineArbitraryByConcept<Unit, typename geometry_concept<typename cT::value_type>::type>::type polyData(at1); //poly_line_arbitrary_polygon_data polyData(at1); //std::cout << "test2\n"; //std::cout << poly << "\n"; //std::cout << "test3\n"; typedef typename cT::value_type result_type; typedef typename geometry_concept<result_type>::type result_concept; output.push_back(result_type()); assign(output.back(), polyData); //std::cout << "test4\n"; //std::cout << "delete " << at1->otherTailp_ << "\n"; //at1->print(); //at1->otherTailp_->print(); delete at1->otherTailp_; //at1->print(); //at1->otherTailp_->print(); //std::cout << "test5\n"; //std::cout << "delete " << at1 << "\n"; delete at1; //std::cout << "test6\n"; return 0; _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
