NEW: first layer printing sequence

Change-Id: I19e39a27cf972eb859e51a334aeae8f57ee263f8
(cherry picked from commit 1369107c04668f800a338395ed3af316c32d194d)

src/slic3r/GUI/DragCanvas.hpp

@@ -0,0 +1,65 @@
+#ifndef slic3r_GUI_DragCanvas_hpp_
+#define slic3r_GUI_DragCanvas_hpp_
+
+#include "wx/bitmap.h"
+#include "wx/dragimag.h"
+
+namespace Slic3r { namespace GUI {
+
+class DragShape : public wxObject
+{
+public:
+    DragShape(const wxBitmap& bitmap, int index);
+    ~DragShape() {}
+
+    wxPoint GetPosition() const { return m_pos; }
+    void SetPosition(const wxPoint& pos) { m_pos = pos; }
+
+    const wxBitmap& GetBitmap() const { return m_bitmap; }
+    void SetBitmap(const wxBitmap& bitmap) { m_bitmap = bitmap; }
+
+    int get_index() { return m_index; }
+
+    bool hit_test(const wxPoint& pt) const;
+    void paint(wxDC& dc, bool highlight = false);
+
+protected:
+    wxPoint     m_pos;
+    wxBitmap    m_bitmap;
+    int         m_index;
+};
+
+
+enum class DragMode {
+    NONE,
+    DRAGGING,
+};
+class DragCanvas : public wxPanel
+{
+public:
+    DragCanvas(wxWindow* parent, const std::vector<std::string>& colors, const std::vector<int>& order);
+    ~DragCanvas();
+    void set_shape_list(const std::vector<std::string>& colors, const std::vector<int>& order);
+    std::vector<int> get_shape_list_order();
+    std::vector<DragShape*> get_ordered_shape_list();
+
+protected:
+    void on_paint(wxPaintEvent& event);
+    void on_erase(wxEraseEvent& event);
+    void on_mouse(wxMouseEvent& event);
+    DragShape* find_shape(const wxPoint& pt) const;
+
+private:
+    std::vector<DragShape*>    m_dragshape_list;
+    DragMode                   m_drag_mode;
+    DragShape*                 m_dragging_shape{ nullptr };
+    DragShape*                 m_slot_shape{ nullptr }; // The shape that's being highlighted
+    wxDragImage*               m_drag_image{ nullptr };
+    wxPoint                    m_drag_start_pos;
+    wxBitmap                   m_arrow_bmp;
+    wxPoint                    m_max_shape_pos;
+};
+
+
+}}
+#endif