libreofficekit/source/gtk/tilebuffer.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #ifndef INCLUDED_TILEBUFFER_HXX
  11 #define INCLUDED_TILEBUFFER_HXX
  12
  13 #include <cairo.h>
  14 #include <gio/gio.h>
  15 #include <glib.h>
  16
  17 #include <map>
  18
  19 #define LOK_TILEBUFFER_ERROR (LOKTileBufferErrorQuark())
  20
  21 // Lets use a square of side 256 pixels for each tile.
  22 const int nTileSizePixels = 256;
  23
  24 /**
  25    Converts the pixel value to zoom independent twip value.
  26
  27    @param fInput value to convert
  28    @param zoom the current zoom level
  29
  30    @return the pixels value corresponding to given twip value
  31 */
  32 float pixelToTwip(float fInput, float zoom);
  33
  34 /**
  35    Converts the zoom independent twip value pixel value.
  36
  37    @param fInput value to convert
  38    @param zoom the current zoom level
  39
  40    @return the twip value corresponding to given pixel value
  41 */
  42 float twipToPixel(float fInput, float zoom);
  43
  44 /**
  45    Gets GQuark identifying this tile buffer errors
  46 */
  47 GQuark LOKTileBufferErrorQuark(void);
  48
  49 /**
  50    This class represents a single tile in the tile buffer.
  51    It encloses a reference to GdkPixBuf containing the pixel data of the tile.
  52 */
  53 class Tile
  54 {
  55 public:
  56     Tile()
  57         : valid(false)
  58         , m_pBuffer(nullptr)
  59     {
  60     }
  61     ~Tile()
  62     {
  63         if (m_pBuffer)
  64             cairo_surface_destroy(m_pBuffer);
  65     }
  66
  67     /**
  68        Tells if this tile is valid or not. Initialised to 0 (invalid) during
  69        object creation.
  70     */
  71     bool valid;
  72
  73     /// Function to get the pointer to enclosing cairo_surface_t
  74     cairo_surface_t* getBuffer();
  75     /// Used to set the pixel buffer of this object
  76     void setSurface(cairo_surface_t*);
  77
  78 private:
  79     /// Pixel buffer data for this tile
  80     cairo_surface_t* m_pBuffer;
  81 };
  82
  83 /**
  84    This class represents the tile buffer which is responsible for managing,
  85    reusing and caching all the already rendered tiles. If the given tile is not
  86    present in the buffer, call to LOK Document's (m_pLOKDocument) paintTile
  87    method is made which fetches the rendered tile from LO core and store it in
  88    buffer for future reuse.
  89 */
  90 class TileBuffer
  91 {
  92 public:
  93     TileBuffer(int columns = 0, int scale = 1)
  94         : m_nWidth(columns)
  95     {
  96         cairo_surface_t* pSurface = cairo_image_surface_create(
  97             CAIRO_FORMAT_ARGB32, nTileSizePixels * scale, nTileSizePixels * scale);
  98         m_DummyTile.setSurface(pSurface);
  99         cairo_surface_destroy(pSurface);
 100     }
 101
 102     /**
 103        Gets the underlying Tile object for given position. The position (0, 0)
 104        points to the left top most tile of the buffer.
 105
 106        If the tile is not cached by the tile buffer, it makes a paintTile call
 107        to LO core asking to render the given tile. It then stores the tile for
 108        future reuse.
 109
 110        @param x the tile along the x-axis of the buffer
 111        @param y the tile along the y-axis of the buffer
 112        @param task GTask object containing the necessary data
 113        @param pool GThreadPool managed by the widget instance used for all the
 114        LOK calls made by widget. It is needed here because getTile invokes one
 115        of the LOK call : paintTile.
 116
 117        @return the tile at the mentioned position (x, y)
 118      */
 119     Tile& getTile(int x, int y, GTask* task, GThreadPool* pool);
 120
 121     /*
 122       Takes ownership of the surface and sets it on a tile at a given location
 123     */
 124     void setTile(int x, int y, cairo_surface_t* surface);
 125
 126     /// Returns true if a valid tile exists at this location
 127     bool hasValidTile(int x, int y);
 128
 129     /// Destroys all the tiles in the tile buffer; also frees the memory allocated
 130     /// for all the Tile objects.
 131     void resetAllTiles();
 132     /**
 133        Marks the tile as invalid. The tile (0, 0) is the left topmost tile in
 134        the tile buffer.
 135
 136        @param x the position of tile along x-axis
 137        @param y the position of tile along y-axis
 138        @param zoom zoom factor of the document
 139        @param task GTask object containing the necessary data
 140        @param pool GThreadPool managed by the widget instance used for all the
 141        LOK calls made by widget. It is needed here because setInvalid() invokes one
 142        of the LOK call : paintTile.
 143      */
 144     void setInvalid(int x, int y, float zoom, GTask* task, GThreadPool*);
 145
 146 private:
 147     /// Stores all the tiles cached by this tile buffer.
 148     std::map<int, Tile> m_mTiles;
 149     /// Width of the current tile buffer (number of columns)
 150     int m_nWidth;
 151     /// Dummy tile
 152     Tile m_DummyTile;
 153 };
 154
 155 enum
 156 {
 157     LOK_LOAD_DOC,
 158     LOK_POST_COMMAND,
 159     LOK_SET_EDIT,
 160     LOK_SET_PARTMODE,
 161     LOK_SET_PART,
 162     LOK_POST_KEY,
 163     LOK_PAINT_TILE,
 164     LOK_POST_MOUSE_EVENT,
 165     LOK_SET_GRAPHIC_SELECTION,
 166     LOK_SET_CLIENT_ZOOM
 167 };
 168
 169 enum
 170 {
 171     LOK_TILEBUFFER_CHANGED,
 172     LOK_TILEBUFFER_MEMORY
 173 };
 174
 175 /**
 176    A struct that we use to store the data about the LOK call.
 177
 178    Object of this type is passed with all the LOK calls,
 179    so that they can be identified. Additionally, it also contains
 180    the data that LOK call needs.
 181 */
 182 struct LOEvent
 183 {
 184     /// To identify the type of LOK call
 185     int m_nType;
 186
 187     /// @name post_command parameters
 188     ///@{
 189     const gchar* m_pCommand;
 190     gchar* m_pArguments;
 191     gboolean m_bNotifyWhenFinished;
 192     ///@}
 193
 194     /// set_edit parameter
 195     gboolean m_bEdit;
 196
 197     /// set_partmode parameter
 198     int m_nPartMode;
 199
 200     /// set_part parameter
 201     int m_nPart;
 202
 203     /// @name postKeyEvent parameters
 204     ///@{
 205     int m_nKeyEvent;
 206     int m_nCharCode;
 207     int m_nKeyCode;
 208     ///@}
 209
 210     /// @name paintTile parameters
 211     ///@{
 212     int m_nPaintTileX;
 213     int m_nPaintTileY;
 214     float m_fPaintTileZoom;
 215     TileBuffer* m_pTileBuffer;
 216     ///@}
 217
 218     /// @name postMouseEvent parameters
 219     ///@{
 220     int m_nPostMouseEventType;
 221     int m_nPostMouseEventX;
 222     int m_nPostMouseEventY;
 223     int m_nPostMouseEventCount;
 224     int m_nPostMouseEventButton;
 225     int m_nPostMouseEventModifier;
 226     ///@}
 227
 228     /// @name setGraphicSelection parameters
 229     ///@{
 230     int m_nSetGraphicSelectionType;
 231     int m_nSetGraphicSelectionX;
 232     int m_nSetGraphicSelectionY;
 233     ///@}
 234
 235     /// @name setClientView parameters
 236     ///@{
 237     int m_nTilePixelWidth;
 238     int m_nTilePixelHeight;
 239     int m_nTileTwipWidth;
 240     int m_nTileTwipHeight;
 241     ///@}
 242
 243     /// Constructor to instantiate an object of type `type`.
 244     explicit LOEvent(int type)
 245         : m_nType(type)
 246         , m_pCommand(nullptr)
 247         , m_pArguments(nullptr)
 248         , m_bNotifyWhenFinished(false)
 249         , m_bEdit(false)
 250         , m_nPartMode(0)
 251         , m_nPart(0)
 252         , m_nKeyEvent(0)
 253         , m_nCharCode(0)
 254         , m_nKeyCode(0)
 255         , m_nPaintTileX(0)
 256         , m_nPaintTileY(0)
 257         , m_fPaintTileZoom(0)
 258         , m_pTileBuffer(nullptr)
 259         , m_nPostMouseEventType(0)
 260         , m_nPostMouseEventX(0)
 261         , m_nPostMouseEventY(0)
 262         , m_nPostMouseEventCount(0)
 263         , m_nPostMouseEventButton(0)
 264         , m_nPostMouseEventModifier(0)
 265         , m_nSetGraphicSelectionType(0)
 266         , m_nSetGraphicSelectionX(0)
 267         , m_nSetGraphicSelectionY(0)
 268         , m_nTilePixelWidth(0)
 269         , m_nTilePixelHeight(0)
 270         , m_nTileTwipWidth(0)
 271         , m_nTileTwipHeight(0)
 272     {
 273     }
 274
 275     /// Wrapper around delete to help GLib.
 276     static void destroy(void* pMemory);
 277 };
 278
 279 #endif // INCLUDED_TILEBUFFER_HXX
 280
 281 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */