// -*- 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
-#include <config.h>
+#include "GraphicsTypes.h"
-#ifdef __GNUG__
-#pragma interface
-#endif
+#include <boost/signals2.hpp>
-#include XPM_H_LOCATION
-#include "LString.h"
-#include "graphics/Renderer.h"
-#include "support/syscall.h"
-#include "sigc++/signal_system.h"
-#ifdef SIGC_CXX_NAMESPACES
-using SigC::Signal0;
-#endif
+namespace lyx {
-/* (Baruch Even 2000-08-05)
- * This has a major drawback: it is only designed for X servers, no easy
- * porting to non X-server based platform is offered right now, this is done
- * in order to get a first version out of the door.
- *
- * Later versions should consider how to do this with more platform
- * independence, this will probably involve changing the Painter class too.
- */
+namespace support { class FileName; }
-/* (Baruch Even 2000-08-05)
- * This should be made reference counted, but for the sake of initial design
- * I'll forego that and just make a first version that actually works, though
- * it may fail or leak in real document, this is an initial design to try
- * ideas on and be a testbed.
- * It may just as well be scraped later on to create a better design based on
- * the results of working with the current design.
- */
+namespace graphics {
-/// A GraphicsCache item holder.
-class GraphicsCacheItem {
+class Image;
+class Converter;
+
+/// A graphics::Cache item holder.
+class CacheItem {
public:
- /// d-tor, frees the image structures.
- ~GraphicsCacheItem();
-
- /// Get the height of the image. Returns -1 on error.
- int getHeight() const { return height_; }
-
- /// Get the width of the image. Returns -1 on error.
- int getWidth() const { return width_; }
-
- /// Return a pixmap that can be displayed on X server.
- Pixmap getImage() const { return pixmap_; }
-
- enum ImageStatus {
- Loading = 1,
- ErrorConverting,
- ErrorReading,
- Loaded
- };
-
- /// Is the pixmap ready for display?
- ImageStatus getImageStatus() const { return imageStatus_; }
-
- /// Get a notification when the image conversion is done.
- /// used by an internal callback mechanism.
- void imageConverted(int retval);
-
- /// A signal objects can connect to in order to know when the image
- /// has arrived.
- Signal0<void> imageDone;
+ ///
+ 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::signals2::signal<void()> sig_type;
+ typedef sig_type::slot_type slot_type;
+ ///
+ boost::signals2::connection connect(slot_type const &) const;
+
private:
- /// Private c-tor so that only GraphicsCache can create an instance.
- GraphicsCacheItem();
-
- /// Set the filename this item will be pointing too.
- bool setFilename(string const & filename);
-
- /// Create an XPM file version of the image.
- bool renderXPM(string const & filename);
-
- /// Load the image from XPM to memory Pixmap
- void loadXPMImage();
-
- ///
- friend class GraphicsCache;
-
- /// The file name of the XPM file.
- string xpmfile;
- /// The image height
- int height_;
- /// The image width
- int width_;
- /// Is the pixmap loaded?
- ImageStatus imageStatus_;
- /// The image pixmap
- Pixmap pixmap_;
- /// The rendering object.
- Renderer * renderer;
-
- /// The system caller, runs the convertor.
- Systemcalls syscall;
+ /// 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
projects / lyx.git / blobdiff