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 // We know that VirtualDevices use a DPI of 96.
  22 const int DPI = 96;
  23 // Lets use a square of side 256 pixels for each tile.
  24 const int nTileSizePixels = 256;
  25
  26 /**
  27    Converts the pixel value to zoom independent twip value.
  28
  29    @param fInput value to convert
  30    @param zoom the current zoom level
  31
  32    @return the pixels value corresponding to given twip value
  33 */
  34 float pixelToTwip(float fInput, float zoom);
  35
  36 /**
  37    Converts the zoom independent twip value pixel value.
  38
  39    @param fInput value to convert
  40    @param zoom the current zoom level
  41
  42    @return the twip value corresponding to given pixel value
  43 */
  44 float twipToPixel(float fInput, float zoom);
  45
  46 /**
  47    Gets GQuark identifying this tile buffer errors
  48 */
  49 GQuark LOKTileBufferErrorQuark(void);
  50
  51 /**
  52    This class represents a single tile in the tile buffer.
  53    It encloses a reference to GdkPixBuf containing the pixel data of the tile.
  54 */
  55 class Tile
  56 {
  57 public:
  58     Tile()
  59         : valid(false)
  60         , m_pBuffer(nullptr)
  61     {
  62     }
  63     ~Tile()
  64     {
  65         if (m_pBuffer)
  66             cairo_surface_destroy(m_pBuffer);
  67     }
  68
  69     /**
  70        Tells if this tile is valid or not. Initialised to 0 (invalid) during
  71        object creation.
  72     */
  73     bool valid;
  74
  75     /// Function to get the pointer to enclosing cairo_surface_t
  76     cairo_surface_t* getBuffer();
  77     /// Used to set the pixel buffer of this object
  78     void setSurface(cairo_surface_t*);
  79
  80 private:
  81     /// Pixel buffer data for this tile
  82     cairo_surface_t* m_pBuffer;
  83 };
  84
  85 /**
  86    This class represents the tile buffer which is responsible for managing,
  87    reusing and caching all the already rendered tiles. If the given tile is not
  88    present in the buffer, call to LOK Document's (m_pLOKDocument) paintTile
  89    method is made which fetches the rendered tile from LO core and store it in
  90    buffer for future reuse.
  91 */
  92 class TileBuffer
  93 {
  94 public:
  95     TileBuffer(int columns = 0, int scale = 1)
  96         : m_nWidth(columns)
  97     {
  98         cairo_surface_t* pSurface = cairo_image_surface_create(
  99             CAIRO_FORMAT_ARGB32, nTileSizePixels * scale, nTileSizePixels * scale);
 100         m_DummyTile.setSurface(pSurface);
 101         cairo_surface_destroy(pSurface);
 102     }
 103
 104     /**
 105        Gets the underlying Tile object for given position. The position (0, 0)
 106        points to the left top most tile of the buffer.
 107
 108        If the tile is not cached by the tile buffer, it makes a paintTile call
 109        to LO core asking to render the given tile. It then stores the tile for
 110        future reuse.
 111
 112        @param x the tile along the x-axis of the buffer
 113        @param y the tile along the y-axis of the buffer
 114        @param task GTask object containing the necessary data
 115        @param pool GThreadPool managed by the widget instance used for all the
 116        LOK calls made by widget. It is needed here because getTile invokes one
 117        of the LOK call : paintTile.
 118
 119        @return the tile at the mentioned position (x, y)
 120      */
 121     Tile& getTile(int x, int y, GTask* task, GThreadPool* pool);
 122
 123     /*
 124       Takes ownership of the surface and sets it on a tile at a given location
 125     */
 126     void setTile(int x, int y, cairo_surface_t* surface);
 127
 128     /// Returns true if a valid tile exists at this location
 129     bool hasValidTile(int x, int y);
 130
 131     /// Destroys all the tiles in the tile buffer; also frees the memory allocated
 132     /// for all the Tile objects.
 133     void resetAllTiles();
 134     /**
 135        Marks the tile as invalid. The tile (0, 0) is the left topmost tile in
 136        the tile buffer.
 137
 138        @param x the position of tile along x-axis
 139        @param y the position of tile along y-axis
 140        @param zoom zoom factor of the document
 141        @param task GTask object containing the necessary data
 142        @param pool GThreadPool managed by the widget instance used for all the
 143        LOK calls made by widget. It is needed here because setInvalid() invokes one
 144        of the LOK call : paintTile.
 145      */
 146     void setInvalid(int x, int y, float zoom, GTask* task, GThreadPool*);
 147
 148 private:
 149     /// Stores all the tiles cached by this tile buffer.
 150     std::map<int, Tile> m_mTiles;
 151     /// Width of the current tile buffer (number of columns)
 152     int m_nWidth;
 153     /// Dummy tile
 154     Tile m_DummyTile;
 155 };
 156
 157 enum
 158 {
 159     LOK_LOAD_DOC,
 160     LOK_POST_COMMAND,
 161     LOK_SET_EDIT,
 162     LOK_SET_PARTMODE,
 163     LOK_SET_PART,
 164     LOK_POST_KEY,
 165     LOK_PAINT_TILE,
 166     LOK_POST_MOUSE_EVENT,
 167     LOK_SET_GRAPHIC_SELECTION,
 168     LOK_SET_CLIENT_ZOOM
 169 };
 170
 171 enum
 172 {
 173     LOK_TILEBUFFER_CHANGED,
 174     LOK_TILEBUFFER_MEMORY
 175 };
 176
 177 /**
 178    A struct that we use to store the data about the LOK call.
 179
 180    Object of this type is passed with all the LOK calls,
 181    so that they can be identified. Additionally, it also contains
 182    the data that LOK call needs.
 183 */
 184 struct LOEvent
 185 {
 186     /// To identify the type of LOK call
 187     int m_nType;
 188
 189     /// @name post_command parameters
 190     ///@{
 191     const gchar* m_pCommand;
 192     gchar* m_pArguments;
 193     gboolean m_bNotifyWhenFinished;
 194     ///@}
 195
 196     /// set_edit parameter
 197     gboolean m_bEdit;
 198
 199     /// set_partmode parameter
 200     int m_nPartMode;
 201
 202     /// set_part parameter
 203     int m_nPart;
 204
 205     /// @name postKeyEvent parameters
 206     ///@{
 207     int m_nKeyEvent;
 208     int m_nCharCode;
 209     int m_nKeyCode;
 210     ///@}
 211
 212     /// @name paintTile parameters
 213     ///@{
 214     int m_nPaintTileX;
 215     int m_nPaintTileY;
 216     float m_fPaintTileZoom;
 217     TileBuffer* m_pTileBuffer;
 218     ///@}
 219
 220     /// @name postMouseEvent parameters
 221     ///@{
 222     int m_nPostMouseEventType;
 223     int m_nPostMouseEventX;
 224     int m_nPostMouseEventY;
 225     int m_nPostMouseEventCount;
 226     int m_nPostMouseEventButton;
 227     int m_nPostMouseEventModifier;
 228     ///@}
 229
 230     /// @name setGraphicSelection parameters
 231     ///@{
 232     int m_nSetGraphicSelectionType;
 233     int m_nSetGraphicSelectionX;
 234     int m_nSetGraphicSelectionY;
 235     ///@}
 236
 237     /// @name setClientView parameters
 238     ///@{
 239     int m_nTilePixelWidth;
 240     int m_nTilePixelHeight;
 241     int m_nTileTwipWidth;
 242     int m_nTileTwipHeight;
 243     ///@}
 244
 245     /// Constructor to instantiate an object of type `type`.
 246     explicit LOEvent(int type)
 247         : m_nType(type)
 248         , m_pCommand(nullptr)
 249         , m_pArguments(nullptr)
 250         , m_bNotifyWhenFinished(false)
 251         , m_bEdit(false)
 252         , m_nPartMode(0)
 253         , m_nPart(0)
 254         , m_nKeyEvent(0)
 255         , m_nCharCode(0)
 256         , m_nKeyCode(0)
 257         , m_nPaintTileX(0)
 258         , m_nPaintTileY(0)
 259         , m_fPaintTileZoom(0)
 260         , m_pTileBuffer(nullptr)
 261         , m_nPostMouseEventType(0)
 262         , m_nPostMouseEventX(0)
 263         , m_nPostMouseEventY(0)
 264         , m_nPostMouseEventCount(0)
 265         , m_nPostMouseEventButton(0)
 266         , m_nPostMouseEventModifier(0)
 267         , m_nSetGraphicSelectionType(0)
 268         , m_nSetGraphicSelectionX(0)
 269         , m_nSetGraphicSelectionY(0)
 270         , m_nTilePixelWidth(0)
 271         , m_nTilePixelHeight(0)
 272         , m_nTileTwipWidth(0)
 273         , m_nTileTwipHeight(0)
 274     {
 275     }
 276
 277     /// Wrapper around delete to help GLib.
 278     static void destroy(void* pMemory);
 279 };
 280
 281 #endif // INCLUDED_TILEBUFFER_HXX
 282
 283 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */