kicad-developers team mailing list archive

[Nick Østergaard <oe.nick@xxxxxxxxx>]

If I am not mistaken, this is also related to:
https://bugs.launchpad.net/kicad/+bug/1056926

Which referers https://svn.boost.org/trac/boost/ticket/7983

Those two boost bugs could be duplicates?

2015-06-01 18:23 GMT+02:00 Tomasz Wlostowski <tomasz.wlostowski@xxxxxxx>:
> 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;
>
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