use Test::More; use strict; use warnings; plan tests => 3; use Math::Clipper ':all'; { my $square = [ # ccw [10, 10], [20, 10], [20, 20], [10, 20], ]; my $hole_in_square = [ # cw [14, 14], [14, 16], [16, 16], [16, 14], ]; my $square2 = [ # ccw [5, 12], [25, 12], [25, 18], [5, 18], ]; my $clipper = Math::Clipper->new; $clipper->add_subject_polygons([ $square, $hole_in_square ]); $clipper->add_clip_polygons([ $square2 ]); my $intersection = $clipper->ex_execute(CT_INTERSECTION, PFT_NONZERO, PFT_NONZERO); is_deeply $intersection, [ { holes => [ [ [14, 16], [16, 16], [16, 14], [14, 14], ], ], outer => [ [10, 18], [10, 12], [20, 12], [20, 18], ], }, ], 'hole is preserved after intersection'; } #========================================================== { my $contour1 = [ [0,0], [40,0], [40,40], [0,40] ]; # ccw my $contour2 = [ [10,10], [30,10], [30,30], [10,30] ]; # ccw my $hole = [ [15,15], [15,25], [25,25], [25,15] ]; # cw my $clipper = Math::Clipper->new; $clipper->add_subject_polygons([ $contour1, $contour2, $hole ]); my $union = $clipper->ex_execute(CT_UNION, PFT_NONZERO, PFT_NONZERO); is_deeply $union, [{ holes => [], outer => [ [0,40], [0,0], [40,0], [40,40] ] }], 'union of two ccw and one cw is a contour with no holes'; $clipper->clear; $clipper->add_subject_polygons([ $contour1, $contour2 ]); $clipper->add_clip_polygons([ $hole ]); my $diff = $clipper->ex_execute(CT_DIFFERENCE, PFT_NONZERO, PFT_NONZERO); is_deeply $diff, [{ holes => [[ [15,25], [25,25], [25,15], [15,15] ]], outer => [ [0,40], [0,0], [40,0], [40,40] ] }], 'difference of a cw from two ccw is a contour with one hole'; }