Merge with bibnikv.

Added some functions to TabIface.
Added BedShapeDialog & Bed2D classes.
Added new_scale to Polygon.
In class Field: Point renamed to PointCtrl and added set_value for PointCtrl, extended get_value for Choice.

xs/src/slic3r/GUI/2DBed.hpp

@@ -0,0 +1,40 @@
+#include <wx/wx.h>
+#include "Config.hpp"
+
+namespace Slic3r {
+namespace GUI {
+
+class Bed_2D : public wxPanel
+{
+	bool		m_user_drawn_background = false;
+
+	bool		m_painted = false;
+	double		m_scale_factor;
+	Pointf		m_shift;
+	Point		m_pos;
+
+	Point		to_pixels(Pointf point);
+	void		repaint();
+public:
+	Bed_2D(wxWindow* parent) 
+	{
+		Create(parent, wxID_ANY, wxDefaultPosition, wxSize(250, -1), wxTAB_TRAVERSAL);
+//		m_user_drawn_background = $^O ne 'darwin';
+		m_user_drawn_background = true;
+		Bind(wxEVT_PAINT, ([this](wxPaintEvent e)
+		{
+			repaint();
+		}));
+//		EVT_ERASE_BACKGROUND($self, sub{}) if $self->{user_drawn_background};
+//		Bind(wxEVT_MOUSE_EVENTS, ([this](wxCommandEvent){/*mouse_event()*/; }));
+		Bind(wxEVT_SIZE, ([this](wxSizeEvent){Refresh(); }));
+	}
+	~Bed_2D(){}
+
+	std::vector<Pointf>		m_bed_shape;
+		
+};
+
+
+} // GUI
+} // Slic3r