diff --git a/t/fill.t b/t/fill.t
index c9cb21391..710e60536 100644
--- a/t/fill.t
+++ b/t/fill.t
@@ -2,7 +2,7 @@ use Test::More;
 use strict;
 use warnings;
 
-plan tests => 93;
+plan tests => 95;
 
 BEGIN {
     use FindBin;
@@ -86,6 +86,23 @@ sub scale_points (@) { map [scale $_->[X], scale $_->[Y]], @_ }
                 'paths don\'t cross hole') or done_testing, exit;
         }
     }
+    
+    # rotated square
+    $filler->set_angle(PI/4);
+    $filler->set_dont_adjust(0);
+    $filler->set_min_spacing(0.654498);
+    $filler->set_endpoints_overlap(unscale(359974));
+    $filler->set_density(1);
+    $filler->set_layer_id(66);
+    $filler->set_z(20.15);
+    {
+        my $e = Slic3r::ExPolygon->new(
+            Slic3r::Polygon->new([25771516,14142125],[14142138,25771515],[2512749,14142131],[14142125,2512749]),
+        );
+        my $paths = $test->($e);
+        is(scalar @$paths, 1, 'one continuous path') or done_testing, exit;
+        ok abs($paths->[0]->length - scale(3*100 + 2*50)) - scaled_epsilon, 'path has expected length';
+    }
 }
 
 {
diff --git a/xs/src/libslic3r/Fill/FillRectilinear.cpp b/xs/src/libslic3r/Fill/FillRectilinear.cpp
index c74da2877..e02c3a298 100644
--- a/xs/src/libslic3r/Fill/FillRectilinear.cpp
+++ b/xs/src/libslic3r/Fill/FillRectilinear.cpp
@@ -37,9 +37,14 @@ FillRectilinear::_fill_single_direction(ExPolygon expolygon,
     if (bounding_box.size().x < min_spacing) return;
     
     // Due to integer rounding, rotated polygons might not preserve verticality
-    // (i.e. when rotating by PI/2 two points having the same x coordinate 
-    // they might get different y coordinates), thus the first line will be skipped.
-    bounding_box.offset(-1);
+    // (i.e. when rotating by PI/2 two points having the same y coordinate 
+    // they might get different x coordinates), thus the first line will be skipped.
+    // Reducing by 1 is not enough, as we observed normal squares being off by about 30
+    // units along x between points supposed to be vertically aligned (coming from an 
+    // axis-aligned polygon edge). We need to be very tolerant here, especially when
+    // making solid infill where lack of lines is visible.
+    bounding_box.min.x += SCALED_EPSILON;
+    bounding_box.max.x -= SCALED_EPSILON;
     
     // define flow spacing according to requested density
     if (this->density > 0.9999f && !this->dont_adjust) {
diff --git a/xs/src/libslic3r/LayerRegionFill.cpp b/xs/src/libslic3r/LayerRegionFill.cpp
index 954f1d135..d6b567ceb 100644
--- a/xs/src/libslic3r/LayerRegionFill.cpp
+++ b/xs/src/libslic3r/LayerRegionFill.cpp
@@ -246,6 +246,12 @@ LayerRegion::make_fill()
         // apply half spacing using this flow's own spacing and generate infill
         f->density = density/100;
         f->dont_adjust = false;
+        /*
+        std::cout << surface.expolygon.dump_perl() << std::endl
+            << " layer_id: " << f->layer_id << " z: " << f->z
+            << " angle: " << f->angle << " min-spacing: " << f->min_spacing
+            << " endpoints_overlap: " << f->endpoints_overlap << std::endl << std::endl;
+        */
         Polylines polylines = f->fill_surface(surface);
         if (polylines.empty())
             continue;