Collect the perimeter surfaces when generating perimeters.

The perimeter surfaces are later used for performing infill
below overhangs and to maintan configured vertical wall thickness
at sloping surfaces.

1 files changed, 23 insertions, 4 deletions

diff --git a/xs/src/libslic3r/Layer.hpp b/xs/src/libslic3r/Layer.hpp
index 4badb8374..23bc84e90 100644
--- a/xs/src/libslic3r/Layer.hpp
+++ b/xs/src/libslic3r/Layer.hpp
@@ -38,6 +38,11 @@ class LayerRegion
     // collection of surfaces for infill generation
     SurfaceCollection fill_surfaces;
 
+    // Collection of perimeter surfaces. This is a cached result of diff(slices, fill_surfaces).
+    // While not necessary, the memory consumption is meager and it speeds up calculation.
+    // The perimeter_surfaces keep the IDs of the slices (top/bottom/)
+    SurfaceCollection perimeter_surfaces;
+
     // collection of expolygons representing the bridged areas (thus not
     // needing support material)
     Polygons bridged;
@@ -56,10 +61,16 @@ class LayerRegion
     Flow flow(FlowRole role, bool bridge = false, double width = -1) const;
     void merge_slices();
     void prepare_fill_surfaces();
-    void make_perimeters(const SurfaceCollection &slices, SurfaceCollection* fill_surfaces);
+    void make_perimeters(const SurfaceCollection &slices, SurfaceCollection* perimeter_surfaces, SurfaceCollection* fill_surfaces);
     void process_external_surfaces(const Layer* lower_layer);
     double infill_area_threshold() const;
-    
+
+    void export_region_slices_to_svg(const char *path);
+    void export_region_fill_surfaces_to_svg(const char *path);
+    // Export to "out/LayerRegion-name-%d.svg" with an increasing index with every export.
+    void export_region_slices_to_svg_debug(const char *name);
+    void export_region_fill_surfaces_to_svg_debug(const char *name);
+
     private:
     Layer *_layer;
     PrintRegion *_region;
@@ -74,7 +85,7 @@ typedef std::vector<LayerRegion*> LayerRegionPtrs;
 class Layer {
     friend class PrintObject;
 
-    public:
+public:
     size_t id() const;
     void set_id(size_t id);
     PrintObject* object();
@@ -91,6 +102,8 @@ class Layer {
     // collection of expolygons generated by slicing the original geometry;
     // also known as 'islands' (all regions and surface types are merged here)
     ExPolygonCollection slices;
+    // Surfaces of the perimeters including their gap fill.
+    ExPolygonCollection perimeter_expolygons;
 
 
     size_t region_count() const;
@@ -102,8 +115,14 @@ class Layer {
     template <class T> bool any_internal_region_slice_contains(const T &item) const;
     template <class T> bool any_bottom_region_slice_contains(const T &item) const;
     void make_perimeters();
+
+    void export_region_slices_to_svg(const char *path);
+    void export_region_fill_surfaces_to_svg(const char *path);
+    // Export to "out/LayerRegion-name-%d.svg" with an increasing index with every export.
+    void export_region_slices_to_svg_debug(const char *name);
+    void export_region_fill_surfaces_to_svg_debug(const char *name);
     
-    protected:
+protected:
     size_t _id;     // sequential number of layer, 0-based
     PrintObject *_object;