1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef INCLUDED_TILEBUFFER_HXX
#define INCLUDED_TILEBUFFER_HXX
#include <gdk/gdkkeysyms.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <map>
#define LOK_USE_UNSTABLE_API
#include <LibreOfficeKit/LibreOfficeKit.h>
#include <LibreOfficeKit/LibreOfficeKitEnums.h>
#include <LibreOfficeKit/LibreOfficeKitGtk.h>
// We know that VirtualDevices use a DPI of 96.
const int DPI = 96;
// Lets use a square of side 256 pixels for each tile.
const int nTileSizePixels = 256;
/**
Converts the pixel value to zoom independent twip value.
@param fInput value to convert
@param zoom the current zoom level
@return the pixels value corresponding to given twip value
*/
float pixelToTwip(float fInput, float zoom);
/**
Converts the zoom independent twip value pixel value.
@param fInput value to convert
@param zoom the current zoom level
@return the twip value corresponding to given pixel value
*/
float twipToPixel(float fInput, float zoom);
/**
This class represents a single tile in the tile buffer.
It encloses a reference to GdkPixBuf containing the pixel data of the tile.
*/
class Tile
{
public:
Tile() : valid(false), m_pBuffer(0) {}
~Tile() { }
/**
Tells if this tile is valid or not. Initialised to 0 (invalid) during
object creation.
*/
bool valid;
/// Function to get the pointer to enclosing GdkPixbuf
GdkPixbuf* getBuffer();
/// Destroys the enclosing GdkPixbuf object pointed to by m_pBuffer
void release();
/// Used to set the pixel buffer of this object
void setPixbuf(GdkPixbuf*);
private:
/// Pixel buffer data for this tile
GdkPixbuf *m_pBuffer;
};
/**
This class represents the tile buffer which is responsible for managing,
reusing and caching all the already rendered tiles. If the given tile is not
present in the buffer, call to LOK Document's (m_pLOKDocument) paintTile
method is made which fetches the rendered tile from LO core and store it in
buffer for future reuse.
*/
class TileBuffer
{
public:
TileBuffer(LibreOfficeKitDocument *document,
int columns)
: m_pLOKDocument(document)
, m_nWidth(columns)
{ }
~TileBuffer() {}
/**
Gets the underlying Tile object for given position. The position (0, 0)
points to the left top most tile of the buffer.
If the tile is not cached by the tile buffer, it makes a paintTile call
to LO core asking to render the given tile. It then stores the tile for
future reuse.
@param x the tile along the x-axis of the buffer
@param y the tile along the y-axis of the buffer
@param aZoom This function needs the zoom factor to draw the tile using paintTile()
@return the tile at the mentioned position (x, y)
*/
Tile& getTile(int x, int y, float aZoom);
/// Destroys all the tiles in the tile buffer; also frees the memory allocated
/// for all the Tile objects.
void resetAllTiles();
/**
Marks the tile as invalid. The tile (0, 0) is the left topmost tile in
the tile buffer.
@param x the position of tile along x-axis
@param y the position of tile along y-axis
*/
void setInvalid(int x, int y);
private:
/// Contains the reference to the LOK Document that this tile buffer is for.
LibreOfficeKitDocument *m_pLOKDocument;
/// Stores all the tiles cached by this tile buffer.
std::map<int, Tile> m_mTiles;
/// Width of the current tile buffer (number of columns)
int m_nWidth;
};
#endif // INCLUDED_TILEBUFFER_HXX
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|
