WIP: Moved sources int src/, separated most of the source code from Perl.

The XS was left only for the unit / integration tests, and it links
libslic3r only. No wxWidgets are allowed to be used from Perl starting
from now.

src/libslic3r/SlicingAdaptive.hpp

@@ -0,0 +1,36 @@
+// Based on implementation by @platsch
+
+#ifndef slic3r_SlicingAdaptive_hpp_
+#define slic3r_SlicingAdaptive_hpp_
+
+#include "Slicing.hpp"
+#include "admesh/stl.h"
+
+namespace Slic3r
+{
+
+class TriangleMesh;
+
+class SlicingAdaptive
+{
+public:
+	void clear();
+	void set_slicing_parameters(SlicingParameters params) { m_slicing_params = params; }
+	void add_mesh(const TriangleMesh *mesh) { m_meshes.push_back(mesh); }
+	void prepare();
+	float cusp_height(float z, float cusp_value, int &current_facet);
+	float horizontal_facet_distance(float z);
+
+protected:
+	SlicingParameters 					m_slicing_params;
+
+	std::vector<const TriangleMesh*>	m_meshes;
+	// Collected faces of all meshes, sorted by raising Z of the bottom most face.
+	std::vector<const stl_facet*>		m_faces;
+	// Z component of face normals, normalized.
+	std::vector<float>					m_face_normal_z;
+};
+
+}; // namespace Slic3r
+
+#endif /* slic3r_SlicingAdaptive_hpp_ */