3 * \file GraphicsImage.h
4 * This file is part of LyX, the document processor.
5 * Licence details can be found in the file COPYING.
8 * \author Angus Leeming
10 * Full author contact details are available in file CREDITS.
12 * An abstract base class for the images themselves.
13 * Allows the user to retrieve the pixmap, once loaded and to issue commands
16 * The boost::functions newImage and loadableFormats are connected to the
17 * appropriate derived classes elsewhere, allowing the graphics cache to
18 * access them without knowing anything about their instantiation.
20 * The loading process can be asynchronous, but cropping, rotating and
21 * scaling block execution.
24 #ifndef GRAPHICSIMAGE_H
25 #define GRAPHICSIMAGE_H
27 #include "Dimension.h"
29 #include <boost/function.hpp>
30 #include <boost/signal.hpp>
36 namespace support { class FileName; }
44 /** This is to be connected to a function that will return a new
45 * instance of a viable derived class.
47 static boost::function<Image *()> newImage;
50 typedef std::vector<std::string> FormatList;
51 /// Return the list of loadable formats.
52 static boost::function<FormatList()> loadableFormats;
58 virtual Image * clone() const = 0;
60 /// Get the image width
61 virtual unsigned int width() const = 0;
63 /// Get the image height
64 virtual unsigned int height() const = 0;
66 /// Is the image drawable ?
67 virtual bool isDrawable() const = 0;
69 /** At the end of the loading process inform the outside world
70 * by emitting a signal
72 typedef boost::signal<void(bool)> SignalType;
74 SignalType finishedLoading;
76 /** Start loading the image file.
77 * The caller should expect this process to be asynchronous and
78 * so should connect to the "finished" signal above.
80 virtual void load(support::FileName const & filename) = 0;
82 /** Generate the pixmap.
83 * Uses the params to decide on color, grayscale etc.
84 * Returns true if the pixmap is created.
86 virtual bool setPixmap(Params const & params) = 0;
88 /// Clip the image using params.
89 virtual void clip(Params const & params) = 0;
91 /// Rotate the image using params.
92 virtual void rotate(Params const & params) = 0;
94 /// Scale the image using params.
95 virtual void scale(Params const & params) = 0;
98 /// Must define default c-tor explicitly as we define a copy c-tor.
100 /// Don't copy the signal finishedLoading
101 Image(Image const &) {}
103 /** Uses the params to ascertain the dimensions of the scaled image.
104 * Returned as Dimension(width, height, 0 descend).
105 * If something goes wrong, returns make_pair(getWidth(), getHeight(), 0)
107 Dimension scaledDimension(Params const & params) const;
111 } // namespace graphics
114 #endif // GRAPHICSIMAGE_H