X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Fgraphics%2FGraphicsCacheItem.h;h=481e4b117a6a770f132daa2c4125f46644ccf547;hb=f345feecede25b164502abdacf893a36de9ef4ae;hp=e139fbffc46a4d24387dbfc728878aab066efc9b;hpb=7110b8eda4ab2dc3e87c53c89225caaff972f9eb;p=lyx.git

diff --git a/src/graphics/GraphicsCacheItem.h b/src/graphics/GraphicsCacheItem.h
index e139fbffc4..481e4b117a 100644
--- a/src/graphics/GraphicsCacheItem.h
+++ b/src/graphics/GraphicsCacheItem.h
@@ -1,29 +1,107 @@
 // -*- C++ -*-
-/* This file is part of
- * =================================================
- * 
- *          LyX, The Document Processor
- *          Copyright 1995 Matthias Ettrich.
- *          Copyright 1995-2000 The LyX Team.
+/**
+ * \file GraphicsCacheItem.h
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
  *
- *          This file Copyright 2000 Baruch Even
- * ================================================= */
+ * \author Baruch Even
+ * \author Angus Leeming
+ *
+ * Full author contact details are available in file CREDITS.
+ *
+ * The graphics cache is a container of graphics::CacheItems.
+ * Each graphics::CacheItem, defined here represents a separate image file.
+ *
+ * The routines here can be used to load the graphics file into memory at
+ * which point (status() == graphics::Loaded).
+ * The user is then free to access image() in order to copy it and to then
+ * transform the copy (rotate, scale, clip) and to generate the pixmap.
+ *
+ * The graphics cache supports fully asynchronous:
+ * file conversion to a loadable format;
+ * file loading.
+ *
+ * Whether you get that, of course, depends on graphics::Converter and
+ * on the graphics::Image-derived image class.
+ */
 
 #ifndef GRAPHICSCACHEITEM_H
 #define GRAPHICSCACHEITEM_H
 
-#ifdef __GNUG__
-#pragma interface
-#endif
+#include "GraphicsTypes.h"
+
+#include <boost/signal.hpp>
+
+
+namespace lyx {
+
+namespace support { class FileName; }
+
+namespace graphics {
+
+class Image;
+class Converter;
 
-///
-class GraphicsCacheItem {
+/// A graphics::Cache item holder.
+class CacheItem {
 public:
+	///
+	CacheItem(support::FileName const & file);
+	/// Needed for the pimpl
+	~CacheItem();
+
+	///
+	support::FileName const & filename() const;
+
+	/// Try to load a display format.
+	bool tryDisplayFormat() const;
+
+	/// It's in the cache. Now start the loading process.
+	void startLoading() const;
+
+	/** Monitor any changes to the file.
+	 *  There is no point monitoring the file before startLoading() is
+	 *  invoked.
+	 */
+	void startMonitoring() const;
+	///
+	bool monitoring() const;
+	/** Returns the check checksum of filename() so that, for example, you can
+	 *  ascertain whether to output a new PostScript version of the file
+	 *  for a LaTeX run.
+	 */
+	unsigned long checksum() const;
+
+	/** Get the image associated with filename().
+	 *  If the image is not yet loaded, returns 0.
+	 *  This routine returns a pointer to const; if you want to modify it,
+	 *  create a copy and modify that.
+	 */
+	Image const * image() const;
+
+	/// How far have we got in loading the image?
+	ImageStatus status() const;
+
+	/** Connect and you'll be informed when the loading status of the image
+	 *  changes.
+	 */
+	typedef boost::signal<void()> sig_type;
+	typedef sig_type::slot_type slot_type;
+	///
+	boost::signals::connection connect(slot_type const &) const;
+
 private:
-    ///
-    GraphicsCacheItem() {}
-    //
-    friend class GraphicsCache;
+	/// noncopyable
+	CacheItem(CacheItem const &);
+	void operator=(CacheItem const &);
+
+	/// Use the Pimpl idiom to hide the internals.
+	class Impl;
+	/// The pointer never changes although *pimpl_'s contents may.
+	Impl * const pimpl_;
 };
 
-#endif
+} // namespace graphics
+} // namespace lyx
+
+#endif // GRAPHICSCACHEITEM_H