Fixed the fill density for rectilinear, triangular and cubic infills.

Initial implementation of the "infill link maximum distance" feature.
Parts of the perimeter connecting two infill lines will be dropped,
if longer than a given threshold.

xs/src/libslic3r/Fill/Fill.hpp

@@ -0,0 +1,33 @@
+#ifndef slic3r_Fill_hpp_
+#define slic3r_Fill_hpp_
+
+#include <memory.h>
+#include <float.h>
+#include <stdint.h>
+
+#include "../libslic3r.h"
+#include "../BoundingBox.hpp"
+#include "../PrintConfig.hpp"
+
+#include "FillBase.hpp"
+
+namespace Slic3r {
+
+class Surface;
+
+// An interface class to Perl, aggregating an instance of a Fill and a FillData.
+class Filler
+{
+public:
+    Filler() : fill(NULL) {}
+    ~Filler() { 
+        delete fill; 
+        fill = NULL;
+    }
+    Fill        *fill;
+    FillParams   params;
+};
+
+} // namespace Slic3r
+
+#endif // slic3r_Fill_hpp_