3 * \file PreviewLoader.h
4 * Copyright 2002 the LyX Team
5 * Read the file COPYING
7 * \author Angus Leeming <a.leeming@ic.ac.uk>
9 * grfx::PreviewLoader collects latex snippets together. Then, on a
10 * startLoading() call, these are dumped to file and processed, converting
11 * each snippet to a separate bitmap image file. Once a bitmap file is ready
12 * to be loaded back into LyX, the PreviewLoader emits a readyToDisplay signal
13 * to inform the initiating process.
16 #ifndef PREVIEWLOADER_H
17 #define PREVIEWLOADER_H
24 #include <boost/utility.hpp>
25 #include <boost/scoped_ptr.hpp>
26 #include <boost/signals/signal1.hpp>
34 class PreviewLoader : boost::noncopyable {
36 /** We need buffer because we require the preamble to the
39 PreviewLoader(Buffer const & buffer);
43 /** Is there an image already associated with this snippet of LaTeX?
44 * If so, returns a pointer to it, else returns 0.
46 PreviewImage const * preview(string const & latex_snippet) const;
60 /// How far have we got in loading the image?
61 Status status(string const & latex_snippet) const;
63 /// Add a snippet of LaTeX to the queue for processing.
64 void add(string const & latex_snippet);
66 /// Remove this snippet of LaTeX from the PreviewLoader.
67 void remove(string const & latex_snippet);
69 /** We have accumulated several latex snippets with status "InQueue".
70 * Initiate their transformation into bitmap images.
74 /// Emit this signal when an image is ready for display.
75 boost::signal1<void, PreviewImage const &> imageReady;
78 /// Use the Pimpl idiom to hide the internals.
80 /// The pointer never changes although *pimpl_'s contents may.
81 boost::scoped_ptr<Impl> const pimpl_;
86 #endif // PREVIEWLOADER_H