2 Copyright (C) 2013 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 #ifndef __CANVAS_IMAGE__
20 #define __CANVAS_IMAGE__
23 #include <boost/shared_ptr.hpp>
24 #include <boost/shared_array.hpp>
26 #include "canvas/visibility.h"
27 #include "canvas/item.h"
29 typedef void (*ImageReleaseCallback)(uint8_t *d, void *arg);
31 namespace ArdourCanvas {
34 class LIBCANVAS_API Image : public Item
37 Image (Canvas *, Cairo::Format, int width, int height);
38 Image (Item*, Cairo::Format, int width, int height);
41 Data (uint8_t *d, int w, int h, int s, Cairo::Format fmt)
47 , destroy_callback(NULL)
52 if (destroy_callback) {
53 destroy_callback(data, destroy_arg);
64 ImageReleaseCallback destroy_callback;
69 * Returns a shared_ptr to a Data object that can be used to
70 * write image data to. The Data object will contain a pointer
71 * to the buffer, along with image properties that may be
72 * useful during the data writing.
74 * Can be called from any thread BUT ..
76 * ... to avoid collisions with Image deletion, some synchronization method
77 * may be required or the use of shared_ptr<Image> or similar.
79 boost::shared_ptr<Data> get_image (bool allocate_data = true);
83 * Queues a Data object to be used to redraw this Image item
84 * at the earliest possible opportunity.
86 * May be called from any thread BUT ...
88 * ... to avoid collisions with Image deletion, some synchronization method
89 * may be required or the use of shared_ptr<Image> or similar.
91 void put_image (boost::shared_ptr<Data>);
93 void render (Rect const &, Cairo::RefPtr<Cairo::Context>) const;
94 void compute_bounding_box () const;
97 Cairo::Format _format;
101 mutable boost::shared_ptr<Data> _current;
102 boost::shared_ptr<Data> _pending;
103 mutable bool _need_render;
104 mutable Cairo::RefPtr<Cairo::Surface> _surface;
107 PBD::Signal0<void> DataReady;
108 PBD::ScopedConnectionList data_connections;