1 files changed, 111 insertions, 0 deletions
diff --git a/libs/canvas/canvas/image.h b/libs/canvas/canvas/image.h
new file mode 100644
index 0000000000..d54edd3827
--- /dev/null
+++ b/libs/canvas/canvas/image.h
@@ -0,0 +1,111 @@
+/*
+    Copyright (C) 2013 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef __CANVAS_IMAGE__
+#define __CANVAS_IMAGE__
+
+#include <stdint.h>
+#include <boost/shared_ptr.hpp>
+#include <boost/shared_array.hpp>
+
+#include "canvas/visibility.h"
+#include "canvas/item.h"
+
+typedef void (*ImageReleaseCallback)(uint8_t *d, void *arg);
+
+namespace ArdourCanvas {
+
+
+class LIBCANVAS_API Image : public Item
+{
+public:
+    Image (Group *, Cairo::Format, int width, int height);
+    
+    struct Data {
+	Data (uint8_t *d, int w, int h, int s, Cairo::Format fmt)
+		: data (d)
+		, width (w)
+		, height (h)
+		, stride (s)
+		, format (fmt)
+		, destroy_callback(NULL)
+		, destroy_arg(NULL)
+	{}
+
+	virtual ~Data () {
+		if (destroy_callback) {
+			destroy_callback(data, destroy_arg);
+		} else {
+			free(data);
+		}
+	}
+
+	uint8_t* data;
+	int width;
+	int height;
+	int stride;
+	Cairo::Format format;
+	ImageReleaseCallback  destroy_callback;
+	void* destroy_arg;
+    };
+
+    /** 
+     * Returns a shared_ptr to a Data object that can be used to 
+     * write image data to. The Data object will contain a pointer
+     * to the buffer, along with image properties that may be
+     * useful during the data writing.
+     * 
+     * Can be called from any thread BUT ..
+     *
+     * ... to avoid collisions with Image deletion, some synchronization method
+     * may be required or the use of shared_ptr<Image> or similar.
+     */
+    boost::shared_ptr<Data> get_image (bool allocate_data = true);
+
+
+    /**
+     * Queues a Data object to be used to redraw this Image item
+     * at the earliest possible opportunity.
+     *
+     * May be called from any thread BUT ...
+     *
+     * ... to avoid collisions with Image deletion, some synchronization method
+     * may be required or the use of shared_ptr<Image> or similar.
+     */
+    void put_image (boost::shared_ptr<Data>);
+
+    void render (Rect const &, Cairo::RefPtr<Cairo::Context>) const;
+    void compute_bounding_box () const;
+
+private:
+    Cairo::Format            _format;
+    int                      _width;
+    int                      _height;
+    int                      _data;
+    mutable boost::shared_ptr<Data>  _current;
+    boost::shared_ptr<Data>  _pending;
+    mutable bool             _need_render;
+    mutable Cairo::RefPtr<Cairo::Surface> _surface;
+
+    void accept_data ();
+    PBD::Signal0<void> DataReady;
+    PBD::ScopedConnectionList data_connections;
+};
+
+}
+#endif