fix brim/skirt issue with support raft:

 * fix skirt distance, to take into account the support
 * fix brim ears: not printed between raft extrusions, but around the area.
supermerill/SuperSlicer#1745

1 files changed, 34 insertions, 12 deletions

diff --git a/src/libslic3r/Print.cpp b/src/libslic3r/Print.cpp
index bfbed9f4c..d4b3f7336 100644
--- a/src/libslic3r/Print.cpp
+++ b/src/libslic3r/Print.cpp
@@ -1987,7 +1987,6 @@ void Print::_make_skirt(const PrintObjectPtrs &objects, ExtrusionEntityCollectio
             std::min(size_t(m_config.skirt_height.value), object->layer_count());
         skirt_height_z = std::max(skirt_height_z, object->m_layers[skirt_layers-1]->print_z);
     }
-    
     // Collect points from all layers contained in skirt height.
     Points points;
     for (const PrintObject *object : objects) {
@@ -2007,12 +2006,26 @@ void Print::_make_skirt(const PrintObjectPtrs &objects, ExtrusionEntityCollectio
             for (const ExtrusionEntity *extrusion_entity : layer->support_fills.entities) {
                 Polylines poly;
                 extrusion_entity->collect_polylines(poly);
-                for (const Polyline &polyline : poly)
+                for (const Polyline& polyline : poly)
                     append(object_points, polyline.points);
             }
         }
-        // Include the brim.
+        // if brim, it superseed object & support for first layer
         if (config().skirt_distance_from_brim) {
+            // get first layer support
+            if (!object->support_layers().empty() && object->support_layers().front()->print_z == object->m_layers[0]->print_z) {
+                Points support_points;
+                for (const ExtrusionEntity* extrusion_entity : object->support_layers().front()->support_fills.entities) {
+                    Polylines poly;
+                    extrusion_entity->collect_polylines(poly);
+                    for (const Polyline& polyline : poly)
+                        append(support_points, polyline.points);
+                }
+                Polygon hull_support = Slic3r::Geometry::convex_hull(support_points);
+                for (const Polygon& poly : offset(hull_support, scale_(object->config().brim_width)))
+                    append(object_points, poly.points);
+            }
+            // get object
             for (const ExPolygon& expoly : object->m_layers[0]->lslices)
                 for (const Polygon& poly : offset(expoly.contour, scale_(object->config().brim_width)))
                     append(object_points, poly.points);
@@ -2415,6 +2428,7 @@ void Print::_make_brim_ears(const Flow &flow, const PrintObjectPtrs &objects, Ex
     ExPolygons unbrimmable_with_support = unbrimmable;
     for (PrintObject *object : objects) {
         ExPolygons object_islands;
+        ExPolygons support_island;
         for (const ExPolygon &expoly : object->m_layers.front()->lslices)
             if (brim_config.brim_inside_holes || brim_config.brim_width_interior > 0)
                 object_islands.push_back(brim_offset==0?expoly:offset_ex(expoly, brim_offset)[0]);
@@ -2423,19 +2437,21 @@ void Print::_make_brim_ears(const Flow &flow, const PrintObjectPtrs &objects, Ex
 
         if (!object->support_layers().empty()) {
             Polygons polys = object->support_layers().front()->support_fills.polygons_covered_by_spacing(flow.spacing_ratio, float(SCALED_EPSILON));
-            for (Polygon poly : polys) {
-                //don't put ears over supports unless it's 100% fill
-                if (object->config().support_material_solid_first_layer) {
-                    object_islands.push_back(brim_offset == 0 ? ExPolygon{ poly } : offset_ex(poly, brim_offset)[0]);
-                } else {
-                    unbrimmable_with_support.push_back(ExPolygon{ poly });
+            //put ears over supports unless it's 100% fill
+            if (object->config().support_material_solid_first_layer) {
+                for (Polygon poly : polys) {
+                        object_islands.push_back(brim_offset == 0 ? ExPolygon{ poly } : offset_ex(poly, brim_offset)[0]);
                 }
+            } else {
+                // offset2 to avoid bits of brim inside the raft
+                append(support_island, offset2_ex(polys, flow.scaled_width() * 2, -flow.scaled_width() * 2));
             }
         }
         islands.reserve(islands.size() + object_islands.size() * object->m_instances.size());
         coord_t ear_detection_length = scale_t(object->config().brim_ears_detection_length.value);
-        for (const PrintInstance &copy_pt : object->m_instances)
-            for (const ExPolygon &poly : object_islands) {
+        // duplicate & translate for each instance
+        for (const PrintInstance& copy_pt : object->m_instances) {
+            for (const ExPolygon& poly : object_islands) {
                 islands.push_back(poly);
                 islands.back().translate(copy_pt.shift.x(), copy_pt.shift.y());
                 Polygon decimated_polygon = poly.contour;
@@ -2450,11 +2466,17 @@ void Print::_make_brim_ears(const Flow &flow, const PrintObjectPtrs &objects, Ex
                         decimated_polygon.points = points;
                     }
                 }
-                for (const Point &p : decimated_polygon.convex_points(brim_config.brim_ears_max_angle.value * PI / 180.0)) {
+                for (const Point& p : decimated_polygon.convex_points(brim_config.brim_ears_max_angle.value* PI / 180.0)) {
                     pt_ears.push_back(p);
                     pt_ears.back() += (copy_pt.shift);
                 }
             }
+            // also for support-fobidden area
+            for (const ExPolygon& poly : support_island) {
+                unbrimmable_with_support.push_back(poly);
+                unbrimmable_with_support.back().translate(copy_pt.shift.x(), copy_pt.shift.y());
+            }
+        }
     }
 
     islands = union_ex(islands, true);