1 files changed, 64 insertions, 0 deletions
diff --git a/src/libslic3r/Fill/FillConcentric.cpp b/src/libslic3r/Fill/FillConcentric.cpp
new file mode 100644
index 000000000..8a3a7ea89
--- /dev/null
+++ b/src/libslic3r/Fill/FillConcentric.cpp
@@ -0,0 +1,64 @@
+#include "../ClipperUtils.hpp"
+#include "../ExPolygon.hpp"
+#include "../Surface.hpp"
+
+#include "FillConcentric.hpp"
+
+namespace Slic3r {
+
+void FillConcentric::_fill_surface_single(
+    const FillParams                &params, 
+    unsigned int                     thickness_layers,
+    const std::pair<float, Point>   &direction, 
+    ExPolygon                       &expolygon, 
+    Polylines                       &polylines_out)
+{
+    // no rotation is supported for this infill pattern
+    BoundingBox bounding_box = expolygon.contour.bounding_box();
+    
+    coord_t min_spacing = scale_(this->spacing);
+    coord_t distance = coord_t(min_spacing / params.density);
+    
+    if (params.density > 0.9999f && !params.dont_adjust) {
+        distance = this->_adjust_solid_spacing(bounding_box.size()(0), distance);
+        this->spacing = unscale<double>(distance);
+    }
+
+    Polygons loops = (Polygons)expolygon;
+    Polygons last  = loops;
+    while (! last.empty()) {
+        last = offset2(last, -(distance + min_spacing/2), +min_spacing/2);
+        loops.insert(loops.end(), last.begin(), last.end());
+    }
+
+    // generate paths from the outermost to the innermost, to avoid
+    // adhesion problems of the first central tiny loops
+    loops = union_pt_chained(loops, false);
+    
+    // split paths using a nearest neighbor search
+    size_t iPathFirst = polylines_out.size();
+    Point last_pos(0, 0);
+    for (const Polygon &loop : loops) {
+        polylines_out.push_back(loop.split_at_index(last_pos.nearest_point_index(loop)));
+        last_pos = polylines_out.back().last_point();
+    }
+
+    // clip the paths to prevent the extruder from getting exactly on the first point of the loop
+    // Keep valid paths only.
+    size_t j = iPathFirst;
+    for (size_t i = iPathFirst; i < polylines_out.size(); ++ i) {
+        polylines_out[i].clip_end(this->loop_clipping);
+        if (polylines_out[i].is_valid()) {
+            if (j < i)
+                polylines_out[j] = std::move(polylines_out[i]);
+            ++ j;
+        }
+    }
+    if (j < polylines_out.size())
+        polylines_out.erase(polylines_out.begin() + j, polylines_out.end());
+    //TODO: return ExtrusionLoop objects to get better chained paths,
+    // otherwise the outermost loop starts at the closest point to (0, 0).
+    // We want the loops to be split inside the G-code generator to get optimum path planning.
+}
+
+} // namespace Slic3r