src/graphics/GraphicsImage.h

   1 // -*- C++ -*-
   2 /**
   3  * \file GraphicsImage.h
   4  * This file is part of LyX, the document processor.
   5  * Licence details can be found in the file COPYING.
   6  *
   7  * \author Baruch Even
   8  * \author Angus Leeming
   9  *
  10  * Full author contact details are available in file CREDITS.
  11  *
  12  * An abstract base class for the images themselves.
  13  * Allows the user to retrieve the pixmap, once loaded and to issue commands
  14  * to modify it.
  15  *
  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.
  19  *
  20  * The loading process can be asynchronous, but cropping, rotating and
  21  * scaling block execution.
  22  */
  23
  24 #ifndef GRAPHICSIMAGE_H
  25 #define GRAPHICSIMAGE_H
  26
  27 #include "Dimension.h"
  28
  29 namespace lyx {
  30
  31 namespace support { class FileName; }
  32
  33 namespace graphics {
  34
  35 class Params;
  36
  37 class Image {
  38 public:
  39         ///
  40         virtual ~Image() {}
  41
  42         /// Create a copy
  43         virtual Image * clone() const = 0;
  44
  45         /// Get the image width
  46         virtual unsigned int width() const = 0;
  47
  48         /// Get the image height
  49         virtual unsigned int height() const = 0;
  50
  51         /// Is the image drawable ?
  52         virtual bool isDrawable() const = 0;
  53
  54         /** Start loading the image file.
  55          *  The caller should expect this process to be asynchronous and
  56          *  so should connect to the "finished" signal above.
  57          */
  58         virtual bool load(support::FileName const & filename) = 0;
  59
  60         /** Generate the pixmap.
  61          *  Uses the params to decide on color, grayscale etc.
  62          *  Returns true if the pixmap is created.
  63          */
  64         virtual bool setPixmap(Params const & params) = 0;
  65 };
  66
  67 /// Only way to create a new Image.
  68 /// Implemented in the frontend.
  69 Image * newImage();
  70
  71 } // namespace graphics
  72 } // namespace lyx
  73
  74 #endif // GRAPHICSIMAGE_H