diff --git a/lib/Slic3r/Print/SupportMaterial.pm b/lib/Slic3r/Print/SupportMaterial.pm
index 4314e4fa6..214a2a634 100644
--- a/lib/Slic3r/Print/SupportMaterial.pm
+++ b/lib/Slic3r/Print/SupportMaterial.pm
@@ -8,7 +8,7 @@ use Slic3r::ExtrusionPath ':roles';
 use Slic3r::Flow ':roles';
 use Slic3r::Geometry qw(epsilon scale scaled_epsilon PI rad2deg deg2rad convex_hull);
 use Slic3r::Geometry::Clipper qw(offset diff union union_ex intersection offset_ex offset2
-    intersection_pl offset2_ex diff_pl);
+    intersection_pl offset2_ex diff_pl diff_ex);
 use Slic3r::Surface ':types';
 
 has 'print_config'      => (is => 'rw', required => 1);
@@ -782,7 +782,7 @@ sub generate_toolpaths {
             my $base_flow   = $_flow;
             
             # find centerline of the external loop/extrusions
-            my $to_infill = offset2_ex($base, +scaled_epsilon, -(scaled_epsilon + $_flow->scaled_width/2));
+            my $to_infill = offset2($base, +scaled_epsilon, -(scaled_epsilon + $_flow->scaled_width/2));
             
             my @paths = ();
             
@@ -796,6 +796,17 @@ sub generate_toolpaths {
                 # use the proper spacing for first layer as we don't need to align
                 # its pattern to the other layers
                 $filler->set_min_spacing($base_flow->spacing);
+                
+                # subtract brim so that it goes around the object fully (and support gets its own brim)
+                if ($self->print_config->brim_width > 0) {
+                    my $d = +scale $self->print_config->brim_width*2;
+                    $to_infill = diff_ex(
+                        $to_infill,
+                        offset($object->get_layer(0)->slices->polygons, $d),
+                    );
+                } else {
+                    $to_infill = union_ex($to_infill);
+                }
             } else {
                 # draw a perimeter all around support infill
                 # TODO: use brim ordering algorithm
@@ -806,10 +817,10 @@ sub generate_toolpaths {
                     mm3_per_mm  => $mm3_per_mm,
                     width       => $_flow->width,
                     height      => $layer->height,
-                ), map @$_, @$to_infill;
+                ), @$to_infill;
                 
                 # TODO: use offset2_ex()
-                $to_infill = offset_ex([ map @$_, @$to_infill ], -$_flow->scaled_spacing);
+                $to_infill = offset_ex($to_infill, -$_flow->scaled_spacing);
             }
             
             my $mm3_per_mm = $base_flow->mm3_per_mm;
diff --git a/t/fill.t b/t/fill.t
index 710e60536..765cfd479 100644
--- a/t/fill.t
+++ b/t/fill.t
@@ -22,7 +22,7 @@ sub scale_points (@) { map [scale $_->[X], scale $_->[Y]], @_ }
 {
     my $print = Slic3r::Print->new;
     my $surface_width = 250;
-    my $distance = Slic3r::Filler::adjust_solid_spacing($surface_width, 47);
+    my $distance = Slic3r::Flow::solid_spacing($surface_width, 47);
     is $distance, 50, 'adjusted solid distance';
     is $surface_width % $distance, 0, 'adjusted solid distance';
 }
diff --git a/xs/src/libslic3r/BridgeDetector.cpp b/xs/src/libslic3r/BridgeDetector.cpp
index f9061e405..228f9a4e6 100644
--- a/xs/src/libslic3r/BridgeDetector.cpp
+++ b/xs/src/libslic3r/BridgeDetector.cpp
@@ -5,24 +5,6 @@
 
 namespace Slic3r {
 
-class BridgeDirectionComparator {
-    public:
-    std::map<double,double> dir_coverage;  // angle => score
-    
-    BridgeDirectionComparator(double _extrusion_width)
-        : extrusion_width(_extrusion_width)
-    {};
-    
-    // the best direction is the one causing most lines to be bridged (thus most coverage)
-    bool operator() (double a, double b) {
-        // Initial sort by coverage only - comparator must obey strict weak ordering
-        return (this->dir_coverage[a] > this->dir_coverage[b]);
-    };
-    
-    private:
-    double extrusion_width;
-};
-
 BridgeDetector::BridgeDetector(const ExPolygon &_expolygon, const ExPolygonCollection &_lower_slices,
     coord_t _extrusion_width)
     : expolygon(_expolygon), lower_slices(_lower_slices), extrusion_width(_extrusion_width),
@@ -59,6 +41,8 @@ BridgeDetector::BridgeDetector(const ExPolygon &_expolygon, const ExPolygonColle
 bool
 BridgeDetector::detect_angle()
 {
+    // Do nothing if the bridging region is completely in the air
+    // and there are no anchors available at the layer below.
     if (this->_edges.empty() || this->_anchors.empty()) return false;
     
     /*  Outset the bridge expolygon by half the amount we used for detecting anchors;
@@ -70,60 +54,65 @@ BridgeDetector::detect_angle()
         bridge in several directions and then sum the length of lines having both
         endpoints within anchors */
     
-    // we test angles according to configured resolution
-    std::vector<double> angles;
-    for (int i = 0; i <= PI/this->resolution; ++i)
-        angles.push_back(i * this->resolution);
-    
-    // we also test angles of each bridge contour
+    // generate the list of candidate angles
+    std::vector<BridgeDirection> candidates;
     {
-        Polygons pp = this->expolygon;
-        for (Polygons::const_iterator p = pp.begin(); p != pp.end(); ++p) {
-            Lines lines = p->lines();
-            for (Lines::const_iterator line = lines.begin(); line != lines.end(); ++line)
-                angles.push_back(line->direction());
+        // we test angles according to configured resolution
+        std::vector<double> angles;
+        for (int i = 0; i <= PI/this->resolution; ++i)
+            angles.push_back(i * this->resolution);
+    
+        // we also test angles of each bridge contour
+        {
+            Polygons pp = this->expolygon;
+            for (Polygons::const_iterator p = pp.begin(); p != pp.end(); ++p) {
+                Lines lines = p->lines();
+                for (Lines::const_iterator line = lines.begin(); line != lines.end(); ++line)
+                    angles.push_back(line->direction());
+            }
         }
-    }
     
-    /*  we also test angles of each open supporting edge
-        (this finds the optimal angle for C-shaped supports) */
-    for (Polylines::const_iterator edge = this->_edges.begin(); edge != this->_edges.end(); ++edge) {
-        if (edge->first_point().coincides_with(edge->last_point())) continue;
-        angles.push_back(Line(edge->first_point(), edge->last_point()).direction());
-    }
-    
-    // remove duplicates
-    double min_resolution = PI/180.0;  // 1 degree
-    std::sort(angles.begin(), angles.end());
-    for (size_t i = 1; i < angles.size(); ++i) {
-        if (Slic3r::Geometry::directions_parallel(angles[i], angles[i-1], min_resolution)) {
-            angles.erase(angles.begin() + i);
-            --i;
+        /*  we also test angles of each open supporting edge
+            (this finds the optimal angle for C-shaped supports) */
+        for (Polylines::const_iterator edge = this->_edges.begin(); edge != this->_edges.end(); ++edge) {
+            if (edge->first_point().coincides_with(edge->last_point())) continue;
+            angles.push_back(Line(edge->first_point(), edge->last_point()).direction());
         }
-    }
-    /*  compare first value with last one and remove the greatest one (PI) 
-        in case they are parallel (PI, 0) */
-    if (Slic3r::Geometry::directions_parallel(angles.front(), angles.back(), min_resolution))
-        angles.pop_back();
     
-    BridgeDirectionComparator bdcomp(this->extrusion_width);
-    std::map<double,double> dir_avg_length;
+        // remove duplicates
+        double min_resolution = PI/180.0;  // 1 degree
+        std::sort(angles.begin(), angles.end());
+        for (size_t i = 1; i < angles.size(); ++i) {
+            if (Slic3r::Geometry::directions_parallel(angles[i], angles[i-1], min_resolution)) {
+                angles.erase(angles.begin() + i);
+                --i;
+            }
+        }
+        /*  compare first value with last one and remove the greatest one (PI) 
+            in case they are parallel (PI, 0) */
+        if (Slic3r::Geometry::directions_parallel(angles.front(), angles.back(), min_resolution))
+            angles.pop_back();
+        
+        for (auto angle : angles)
+            candidates.push_back(BridgeDirection(angle));
+    }
+    
     double line_increment = this->extrusion_width;
     bool have_coverage = false;
-    for (std::vector<double>::const_iterator angle = angles.begin(); angle != angles.end(); ++angle) {
+    for (BridgeDirection &candidate : candidates) {
         Polygons my_clip_area = clip_area;
         ExPolygons my_anchors = this->_anchors;
         
         // rotate everything - the center point doesn't matter
-        for (Polygons::iterator it = my_clip_area.begin(); it != my_clip_area.end(); ++it)
-            it->rotate(-*angle, Point(0,0));
-        for (ExPolygons::iterator it = my_anchors.begin(); it != my_anchors.end(); ++it)
-            it->rotate(-*angle, Point(0,0));
+        for (Polygon &p : my_clip_area)
+            p.rotate(-candidate.angle, Point(0,0));
+        for (ExPolygon &e : my_anchors)
+            e.rotate(-candidate.angle, Point(0,0));
     
         // generate lines in this direction
         BoundingBox bb;
-        for (ExPolygons::const_iterator it = my_anchors.begin(); it != my_anchors.end(); ++it)
-            bb.merge((Points)*it);
+        for (const ExPolygon &e : my_anchors)
+            bb.merge((Points)e);
         
         Lines lines;
         for (coord_t y = bb.min.y; y <= bb.max.y; y += line_increment)
@@ -143,44 +132,39 @@ BridgeDetector::detect_angle()
         
         std::vector<double> lengths;
         double total_length = 0;
-        for (Lines::const_iterator line = clipped_lines.begin(); line != clipped_lines.end(); ++line) {
-            double len = line->length();
+        for (const Line &line : clipped_lines) {
+            const double len = line.length();
             lengths.push_back(len);
             total_length += len;
         }
         if (total_length) have_coverage = true;
         
         // sum length of bridged lines
-        bdcomp.dir_coverage[*angle] = total_length;
+        candidate.coverage = total_length;
         
         /*  The following produces more correct results in some cases and more broken in others.
             TODO: investigate, as it looks more reliable than line clipping. */
         // $directions_coverage{$angle} = sum(map $_->area, @{$self->coverage($angle)}) // 0;
         
         // max length of bridged lines
-        dir_avg_length[*angle] = !lengths.empty()
-            ? *std::max_element(lengths.begin(), lengths.end())
-            : 0;
+        if (!lengths.empty())
+            candidate.max_length = *std::max_element(lengths.begin(), lengths.end());
     }
     
     // if no direction produced coverage, then there's no bridge direction
     if (!have_coverage) return false;
     
     // sort directions by coverage - most coverage first
-    std::sort(angles.begin(), angles.end(), bdcomp);
-    this->angle = angles.front();
+    std::sort(candidates.begin(), candidates.end());
     
     // if any other direction is within extrusion width of coverage, prefer it if shorter
     // TODO: There are two options here - within width of the angle with most coverage, or within width of the currently perferred?
-    double most_coverage_angle = this->angle;
-    for (std::vector<double>::const_iterator angle = angles.begin() + 1;
-        angle != angles.end() && bdcomp.dir_coverage[most_coverage_angle] - bdcomp.dir_coverage[*angle] < this->extrusion_width;
-        ++angle
-    ) {
-        if (dir_avg_length[*angle] < dir_avg_length[this->angle]) {
-            this->angle = *angle;
-        }
-    }
+    size_t i_best = 0;
+    for (size_t i = 1; i < candidates.size() && candidates[i_best].coverage - candidates[i].coverage < this->extrusion_width; ++ i)
+        if (candidates[i].max_length < candidates[i_best].max_length)
+            i_best = i;
+    
+    this->angle = candidates[i_best].angle;
     
     if (this->angle >= PI) this->angle -= PI;
     
diff --git a/xs/src/libslic3r/BridgeDetector.hpp b/xs/src/libslic3r/BridgeDetector.hpp
index bbbd26df9..3ba054f5d 100644
--- a/xs/src/libslic3r/BridgeDetector.hpp
+++ b/xs/src/libslic3r/BridgeDetector.hpp
@@ -31,6 +31,19 @@ private:
     Polylines _edges;
     // Closed polygons representing the supporting areas.
     ExPolygons _anchors;
+    
+    class BridgeDirection {
+        public:
+        BridgeDirection(double a = -1.) : angle(a), coverage(0.), max_length(0.) {}
+        // the best direction is the one causing most lines to be bridged (thus most coverage)
+        bool operator<(const BridgeDirection &other) const {
+            // Initial sort by coverage only - comparator must obey strict weak ordering
+            return this->coverage > other.coverage;
+        };
+        double angle;
+        double coverage;
+        double max_length;
+    };
 };
 
 }
diff --git a/xs/src/libslic3r/Fill/Fill.cpp b/xs/src/libslic3r/Fill/Fill.cpp
index c88a32514..39c9107b9 100644
--- a/xs/src/libslic3r/Fill/Fill.cpp
+++ b/xs/src/libslic3r/Fill/Fill.cpp
@@ -1,3 +1,6 @@
+#define DEBUG
+#undef NDEBUG
+#include <cassert>
 #include <math.h>
 #include <stdio.h>
 
@@ -69,36 +72,6 @@ Fill::fill_surface(const Surface &surface)
     return polylines_out;
 }
 
-// Calculate a new spacing to fill width with possibly integer number of lines,
-// the first and last line being centered at the interval ends.
-// This function possibly increases the spacing, never decreases, 
-// and for a narrow width the increase in spacing may become severe,
-// therefore the adjustment is limited to 20% increase.
-coord_t
-Fill::adjust_solid_spacing(const coord_t width, const coord_t distance)
-{
-    assert(width >= 0);
-    assert(distance > 0);
-    const int number_of_intervals = floor(width / distance);
-    if (number_of_intervals == 0) return distance;
-    
-    coord_t distance_new = (width / number_of_intervals);
-    
-    const coordf_t factor = coordf_t(distance_new) / coordf_t(distance);
-    assert(factor > 1. - 1e-5);
-    
-    // How much could the extrusion width be increased? By 20%.
-    // Because of this limit, this method is not idempotent: each run
-    // will increment distance by 20%.
-    const coordf_t factor_max = 1.2;
-    if (factor > factor_max)
-        distance_new = floor((double)distance * factor_max + 0.5);
-    
-    assert((distance_new * number_of_intervals) <= width);
-    
-    return distance_new;
-}
-
 // Returns orientation of the infill and the reference point of the infill pattern.
 // For a normal print, the reference point is the center of a bounding box of the STL.
 Fill::direction_t
diff --git a/xs/src/libslic3r/Fill/Fill.hpp b/xs/src/libslic3r/Fill/Fill.hpp
index abb9e1c65..a72d5528c 100644
--- a/xs/src/libslic3r/Fill/Fill.hpp
+++ b/xs/src/libslic3r/Fill/Fill.hpp
@@ -64,7 +64,6 @@ public:
 public:
     static Fill* new_from_type(const InfillPattern type);
     static Fill* new_from_type(const std::string &type);
-    static coord_t adjust_solid_spacing(const coord_t width, const coord_t distance);
     virtual Fill* clone() const = 0;
     virtual ~Fill() {};
     
diff --git a/xs/src/libslic3r/Fill/FillConcentric.cpp b/xs/src/libslic3r/Fill/FillConcentric.cpp
index 24d8f318a..992dfaa3b 100644
--- a/xs/src/libslic3r/Fill/FillConcentric.cpp
+++ b/xs/src/libslic3r/Fill/FillConcentric.cpp
@@ -1,5 +1,6 @@
 #include "../ClipperUtils.hpp"
 #include "../ExPolygon.hpp"
+#include "../Flow.hpp"
 #include "../Surface.hpp"
 
 #include "FillConcentric.hpp"
@@ -20,7 +21,7 @@ FillConcentric::_fill_surface_single(
     
     if (this->density > 0.9999f && !this->dont_adjust) {
         BoundingBox bounding_box = expolygon.contour.bounding_box();
-        distance = this->adjust_solid_spacing(bounding_box.size().x, distance);
+        distance = Flow::solid_spacing(bounding_box.size().x, distance);
         this->_spacing = unscale(distance);
     }
 
diff --git a/xs/src/libslic3r/Fill/FillRectilinear.cpp b/xs/src/libslic3r/Fill/FillRectilinear.cpp
index e02c3a298..bfee321ed 100644
--- a/xs/src/libslic3r/Fill/FillRectilinear.cpp
+++ b/xs/src/libslic3r/Fill/FillRectilinear.cpp
@@ -6,6 +6,7 @@
 
 #include "../ClipperUtils.hpp"
 #include "../ExPolygon.hpp"
+#include "../Flow.hpp"
 #include "../PolylineCollection.hpp"
 #include "../Surface.hpp"
 #include <algorithm>
@@ -48,7 +49,7 @@ FillRectilinear::_fill_single_direction(ExPolygon expolygon,
     
     // define flow spacing according to requested density
     if (this->density > 0.9999f && !this->dont_adjust) {
-        line_spacing = this->adjust_solid_spacing(bounding_box.size().x, line_spacing);
+        line_spacing = Flow::solid_spacing(bounding_box.size().x, line_spacing);
         this->_spacing = unscale(line_spacing);
     } else {
         // extend bounding box so that our pattern will be aligned with other layers
diff --git a/xs/src/libslic3r/Flow.cpp b/xs/src/libslic3r/Flow.cpp
index 6131534e7..42caf9f1a 100644
--- a/xs/src/libslic3r/Flow.cpp
+++ b/xs/src/libslic3r/Flow.cpp
@@ -50,6 +50,11 @@ Flow::spacing() const {
     return this->width - OVERLAP_FACTOR * (this->width - min_flow_spacing);
 }
 
+void
+Flow::set_spacing(float spacing) {
+    this->width = Flow::_width_from_spacing(spacing, this->nozzle_diameter, this->height, this->bridge);
+}
+
 /* This method returns the centerline spacing between an extrusion using this
    flow and another one using another flow.
    this->spacing(other) shall return the same value as other.spacing(*this) */
@@ -115,4 +120,37 @@ Flow::_width_from_spacing(float spacing, float nozzle_diameter, float height, bo
     return spacing + OVERLAP_FACTOR * height * (1 - PI/4.0);
 }
 
+// Calculate a new spacing to fill width with possibly integer number of lines,
+// the first and last line being centered at the interval ends.
+// This function possibly increases the spacing, never decreases, 
+// and for a narrow width the increase in spacing may become severe,
+// therefore the adjustment is limited to 20% increase.
+template <class T>
+T
+Flow::solid_spacing(const T total_width, const T spacing)
+{
+    assert(total_width >= 0);
+    assert(spacing > 0);
+    const int number_of_intervals = floor(total_width / spacing);
+    if (number_of_intervals == 0) return spacing;
+    
+    T spacing_new = (total_width / number_of_intervals);
+    
+    const double factor = (double)spacing_new / (double)spacing;
+    assert(factor > 1. - 1e-5);
+    
+    // How much could the extrusion width be increased? By 20%.
+    // Because of this limit, this method is not idempotent: each run
+    // will increment spacing by 20%.
+    const double factor_max = 1.2;
+    if (factor > factor_max)
+        spacing_new = floor((double)spacing * factor_max + 0.5);
+    
+    assert((spacing_new * number_of_intervals) <= total_width);
+    
+    return spacing_new;
+}
+template coord_t Flow::solid_spacing<coord_t>(const coord_t total_width, const coord_t spacing);
+template coordf_t Flow::solid_spacing<coordf_t>(const coordf_t total_width, const coordf_t spacing);
+
 }
diff --git a/xs/src/libslic3r/Flow.hpp b/xs/src/libslic3r/Flow.hpp
index fdfcac695..7149df6b4 100644
--- a/xs/src/libslic3r/Flow.hpp
+++ b/xs/src/libslic3r/Flow.hpp
@@ -30,6 +30,13 @@ class Flow
         : width(_w), height(_h), nozzle_diameter(_nd), bridge(_bridge) {};
     float spacing() const;
     float spacing(const Flow &other) const;
+    void set_spacing(float spacing);
+    void set_solid_spacing(const coord_t total_width) {
+        this->set_spacing(Flow::solid_spacing(total_width, this->scaled_spacing()));
+    };
+    void set_solid_spacing(const coordf_t total_width) {
+        this->set_spacing(Flow::solid_spacing(total_width, (coordf_t)this->spacing()));
+    };
     double mm3_per_mm() const;
     coord_t scaled_width() const {
         return scale_(this->width);
@@ -43,12 +50,12 @@ class Flow
     
     static Flow new_from_config_width(FlowRole role, const ConfigOptionFloatOrPercent &width, float nozzle_diameter, float height, float bridge_flow_ratio);
     static Flow new_from_spacing(float spacing, float nozzle_diameter, float height, bool bridge);
+    template <class T> static T solid_spacing(const T total_width, const T spacing);
     
     private:
     static float _bridge_width(float nozzle_diameter, float bridge_flow_ratio);
     static float _auto_width(FlowRole role, float nozzle_diameter, float height);
     static float _width_from_spacing(float spacing, float nozzle_diameter, float height, bool bridge);
-    static float _spacing(float width, float nozzle_diameter, float height, float bridge_flow_ratio);
 };
 
 }
diff --git a/xs/src/libslic3r/Print.cpp b/xs/src/libslic3r/Print.cpp
index 36ce27a8a..deb1d3135 100644
--- a/xs/src/libslic3r/Print.cpp
+++ b/xs/src/libslic3r/Print.cpp
@@ -163,6 +163,10 @@ Print::invalidate_state_by_config(const PrintConfigBase &config)
             || opt_key == "min_skirt_length"
             || opt_key == "ooze_prevention") {
             steps.insert(psSkirt);
+        } else if (opt_key == "brim_width") {
+            steps.insert(psBrim);
+            steps.insert(psSkirt);
+            osteps.insert(posSupportMaterial);
         } else if (opt_key == "brim_width"
             || opt_key == "interior_brim_width"
             || opt_key == "brim_connections_width") {
@@ -759,13 +763,18 @@ Print::brim_flow() const
        extruders and take the one with, say, the smallest index.
        The same logic should be applied to the code that selects the extruder during G-code
        generation as well. */
-    return Flow::new_from_config_width(
+    Flow flow = Flow::new_from_config_width(
         frPerimeter,
         width, 
         this->config.nozzle_diameter.get_at(this->regions.front()->config.perimeter_extruder-1),
         this->skirt_first_layer_height(),
         0
     );
+    
+    // Adjust extrusion width in order to fill the total brim width with an integer number of lines.
+    flow.set_solid_spacing(this->config.brim_width.value);
+    
+    return flow;
 }
 
 Flow
@@ -844,8 +853,8 @@ Print::_make_brim()
         // perimeters because here we're offsetting outwards)
         append_to(loops, offset2(
             islands,
-            flow.scaled_width() + flow.scaled_spacing() * (i - 1.0 + 0.5),
-            flow.scaled_spacing() * -1.0,
+            flow.scaled_width() + flow.scaled_spacing() * (i - 1.5 + 0.5),
+            flow.scaled_spacing() * -0.5,
             100000,
             ClipperLib::jtSquare
         ));
diff --git a/xs/xsp/Filler.xsp b/xs/xsp/Filler.xsp
index 0c5c08b6c..3208ac29a 100644
--- a/xs/xsp/Filler.xsp
+++ b/xs/xsp/Filler.xsp
@@ -78,8 +78,3 @@ new_from_type(CLASS, type)
 %}
 
 };
-
-%package{Slic3r::Filler};
-
-coord_t adjust_solid_spacing(coord_t width, coord_t distance)
-    %code{% RETVAL = Fill::adjust_solid_spacing(width, distance); %};
diff --git a/xs/xsp/Flow.xsp b/xs/xsp/Flow.xsp
index d09f0b351..05cc828b9 100644
--- a/xs/xsp/Flow.xsp
+++ b/xs/xsp/Flow.xsp
@@ -81,3 +81,6 @@ _constant()
 
 %}
 
+coord_t solid_spacing(coord_t width, coord_t distance)
+    %code{% RETVAL = Flow::solid_spacing(width, distance); %};
+