1 /* === S Y N F I G ========================================================= */
2 /*! \file layer_pastecanvas.h
3 ** \brief Header file for implementation of the "Paste Canvas" layer
8 ** Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
9 ** Copyright (c) 2007, 2008 Chris Moore
11 ** This package is free software; you can redistribute it and/or
12 ** modify it under the terms of the GNU General Public License as
13 ** published by the Free Software Foundation; either version 2 of
14 ** the License, or (at your option) any later version.
16 ** This package is distributed in the hope that it will be useful,
17 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ** General Public License for more details.
22 /* ========================================================================= */
24 /* === S T A R T =========================================================== */
26 #ifndef __SYNFIG_LAYER_PASTEIMAGE_H
27 #define __SYNFIG_LAYER_PASTEIMAGE_H
29 /* === H E A D E R S ======================================================= */
31 #include "layer_composite.h"
36 #include "canvasbase.h"
40 /* === M A C R O S ========================================================= */
42 /* === T Y P E D E F S ===================================================== */
44 /* === C L A S S E S & S T R U C T S ======================================= */
48 class Layer_PasteCanvas : public Layer_Composite, public Layer_NoDeform
50 SYNFIG_LAYER_MODULE_EXT
56 etl::loose_handle<synfig::Canvas> canvas;
58 //! Recursion depth counter
65 mutable Time curr_time;
73 sigc::connection child_changed_connection;
75 // Nasty hack: Remember whether we called an extra ref() when
76 // setting the canvas, so we know whether to call an extra unref()
77 // when finished with the canvas.
81 // The root canvas is destructed first. That sets the
82 // Layer::canvas_ (the parent canvas) of any PasteCanvas layer it
83 // contains to nil, due to a call to Layer::set_canvas(0),
84 // triggered by the connection made when Layer::set_canvas
85 // originally set its canvas_ member to point to the root canvas.
86 // ~Canvas does begin_delete() which triggers that connection.
88 // After ~Canvas has run, the members of the root canvas are
89 // freed, including its children_ list. If this was the last
90 // reference to the child canvas that the pastecanvas uses, that
91 // child canvas will Layer_PasteCanvas::set_sub_canvas(0) on the
92 // PasteCanvas layer to set its canvas (the child, pasted canvas)
93 // not to refer to the soon-to-be destroys child canvas. But
94 // set_sub_canvas() originally looked at the value of
95 // Layer::canvas_ (the parent canvas, obtained via
96 // Layer::get_canvas()) to decide whether to do an extra ref() on
97 // canvas (the child canvas). We need to unref() it now if we
98 // did, but we've forgotten whether we did. So we use this
99 // 'extra_reference' member to store that decision.
100 bool extra_reference;
103 -- ** -- S I G N A L S -------------------------------------------------------
108 sigc::signal<void> signal_subcanvas_changed_;
111 -- ** -- S I G N A L I N T E R F A C E -------------------------------------
116 sigc::signal<void>& signal_subcanvas_changed() { return signal_subcanvas_changed_; }
120 void update_renddesc();
122 virtual void on_canvas_set();
124 void set_muck_with_time(bool x=false) { muck_with_time_=x; }
126 etl::handle<synfig::Canvas> get_sub_canvas()const { return canvas; }
127 void set_sub_canvas(etl::handle<synfig::Canvas> x);
129 Real get_zoom()const { return zoom; }
131 Time get_time_offset()const { return time_offset; }
133 Point get_origin()const { return origin; }
136 virtual ~Layer_PasteCanvas();
138 virtual String get_local_name()const;
140 virtual bool set_param(const String & param, const synfig::ValueBase &value);
142 virtual ValueBase get_param(const String & param)const;
144 virtual Color get_color(Context context, const Point &pos)const;
146 virtual void set_time(Context context, Time time)const;
148 virtual bool accelerated_render(Context context,Surface *surface,int quality, const RendDesc &renddesc, ProgressCallback *cb)const;
150 virtual Vocab get_param_vocab()const;
152 virtual synfig::Rect get_bounding_rect()const;
154 virtual synfig::Layer::Handle hit_check(synfig::Context context, const synfig::Point &point)const;
157 virtual void get_times_vfunc(Node::time_set &set) const;
159 }; // END of class Layer_PasteCanvas
161 }; // END of namespace synfig
163 /* === E N D =============================================================== */