Cleanup lines resulting from plane intersection before detecting polygons. This allows for more tolerance with dirty models. Performance impact depends on how many layers are detected as dirty. #16 #28

t/collinear.t

@@ -0,0 +1,91 @@
+use Test::More;
+use strict;
+use warnings;
+
+plan tests => 11;
+
+BEGIN {
+    use FindBin;
+    use lib "$FindBin::Bin/../lib";
+}
+
+use Slic3r;
+use Slic3r::Geometry qw(collinear);
+
+#==========================================================
+
+{
+    my @lines = (
+        [ [0,4], [4,2] ],
+        [ [2,3], [8,0] ],
+        [ [6,1], [8,0] ],
+    );
+    is collinear($lines[0], $lines[1]), 1, 'collinear';
+    is collinear($lines[1], $lines[2]), 1, 'collinear';
+    is collinear($lines[0], $lines[2]), 1, 'collinear';
+}
+
+#==========================================================
+
+{
+    # horizontal
+    my @lines = (
+        [ [0,1], [5,1] ],
+        [ [2,1], [8,1] ],
+    );
+    is collinear($lines[0], $lines[1]), 1, 'collinear';
+}
+
+#==========================================================
+
+{
+    # vertical
+    my @lines = (
+        [ [1,0], [1,5] ],
+        [ [1,2], [1,8] ],
+    );
+    is collinear($lines[0], $lines[1]), 1, 'collinear';
+}
+
+#==========================================================
+
+{
+    # non overlapping
+    my @lines = (
+        [ [0,1], [5,1] ],
+        [ [7,1], [10,1] ],
+    );
+    is collinear($lines[0], $lines[1], 1), 0, 'non overlapping';
+    is collinear($lines[0], $lines[1], 0), 1, 'overlapping';
+}
+
+#==========================================================
+
+{
+    # with one common point
+    my @lines = (
+        [ [0,4], [4,2] ],
+        [ [4,2], [8,0] ],
+    );
+    is collinear($lines[0], $lines[1], 1), 1, 'one common point';
+    is collinear($lines[0], $lines[1], 0), 1, 'one common point';
+}
+
+#==========================================================
+
+{
+    # not collinear
+    my @lines = (
+        [ [290000000,690525600], [285163380,684761540] ],
+        [ [285163380,684761540], [193267599,575244400] ],
+    );
+    is collinear($lines[0], $lines[1], 0), 0, 'not collinear';
+    is collinear($lines[0], $lines[1], 1), 0, 'not collinear';
+    
+    use Slic3r::SVG;
+    Slic3r::SVG::output(undef, "collinear.svg",
+        lines => \@lines,
+    );
+}
+
+#==========================================================