Preparation for new infill

src/libslic3r/Fill/FillBase.hpp

@@ -19,6 +19,10 @@ class ExPolygon;
 class Surface;
 enum InfillPattern : int;
 
+namespace FillAdaptive_Internal {
+    struct Octree;
+};
+
 class InfillFailedException : public std::runtime_error {
 public:
     InfillFailedException() : std::runtime_error("Infill failed") {}
@@ -69,6 +73,8 @@ public:
     // In scaled coordinates. Bounding box of the 2D projection of the object.
     BoundingBox bounding_box;
 
+    FillAdaptive_Internal::Octree* adapt_fill_octree = nullptr;
+
 public:
     virtual ~Fill() {}