summaryrefslogtreecommitdiffstats
path: root/doc/src/files-and-resources/datastreamformat.qdoc
blob: 6eaf606843e4925ac4b930512ccd3962e8db0e11 (plain)
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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights.  These rights are described in the Nokia Qt LGPL
** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

/*!
    \page datastreamformat.html
    \title Format of the QDataStream Operators
    \brief Representations of data types that can be serialized by QDataStream.

    The \l QDataStream allows you to serialize some of the Qt data types.
    The table below lists the data types that QDataStream can serialize
    and how they are represented. The format described below is
    \l{QDataStream::setVersion()}{version 8}.

    It is always best to cast integers to a Qt integer type, such as
    qint16 or quint32, when reading and writing. This ensures that
    you always know exactly what size integers you are reading and
    writing, no matter what the underlying platform and architecture
    the application happens to be running on.

    \table
    \row \o bool
	 \o \list
	    \o boolean
	    \endlist
    \row \o qint8
         \o \list
            \o signed byte
            \endlist
    \row \o qint16
         \o \list
            \o signed 16-bit integer
            \endlist
    \row \o qint32
         \o \list
            \o signed 32-bit integer
            \endlist
    \row \o qint64
         \o \list
            \o signed 64-bit integer
            \endlist
    \row \o quint8
         \o \list
            \o unsigned byte
            \endlist
    \row \o quint16
         \o \list
            \o unsigned 16-bit integer
            \endlist
    \row \o quint32
         \o \list
            \o unsigned 32-bit integer
            \endlist
    \row \o quint64
         \o \list
            \o unsigned 64-bit integer
            \endlist
    \row \o \c float
         \o \list
            \o 32-bit floating point number using the standard IEEE 754 format
            \endlist
    \row \o \c double
         \o \list
            \o 64-bit floating point number using the standard IEEE 754 format
            \endlist
    \row \o \c {const char *}
         \o \list
            \o The string length (quint32)
            \o The string bytes, excluding the terminating 0
            \endlist
    \row \o QBitArray
         \o \list
            \o The array size (quint32)
            \o The array bits, i.e. (size + 7)/8 bytes
            \endlist
    \row \o QBrush
         \o \list
            \o The brush style (quint8)
            \o The brush color (QColor)
            \o If style is CustomPattern, the brush pixmap (QPixmap)
            \endlist
    \row \o QByteArray
         \o \list
            \o If the byte array is null: 0xFFFFFFFF (quint32)
            \o Otherwise: the array size (quint32) followed by the array bytes, i.e. size bytes
            \endlist
    \row \o \l QColor
         \o \list
            \o Color spec (qint8)
            \o Alpha value (quint16)
            \o Red value (quint16)
            \o Green value (quint16)
            \o Blue value (quint16)
            \o Pad value (quint16)
            \endlist
    \row \o QCursor
         \o \list
            \o Shape ID (qint16)
            \o If shape is BitmapCursor: The bitmap (QPixmap), mask (QPixmap), and hot spot (QPoint)
            \endlist
    \row \o QDate
         \o \list
            \o Julian day (quint32)
            \endlist
    \row \o QDateTime
         \o \list
            \o Date (QDate)
            \o Time (QTime)
            \o 0 for Qt::LocalTime, 1 for Qt::UTC (quint8)
            \endlist
    \row \o QFont
         \o \list
            \o The family (QString)
            \o The point size (qint16)
            \o The style hint (quint8)
            \o The char set (quint8)
            \o The weight (quint8)
            \o The font bits (quint8)
            \endlist
    \row \o QHash<Key, T>
         \o \list
            \o The number of items (quint32)
            \o For all items, the key (Key) and value (T)
            \endlist
    \row \o QIcon
         \o \list
            \o The number of pixmap entries (quint32)
            \o For all pixmap entries:
               \list
               \o The pixmap (QPixmap)
               \o The file name (QString)
               \o The pixmap size (QSize)
               \o The \l{QIcon::Mode}{mode} (quint32)
               \o The \l{QIcon::State}{state} (quint32)
               \endlist
            \endlist
    \row \o QImage
         \o \list
            \o If the image is null a "null image" marker is saved;
            otherwise the image is saved in PNG or BMP format (depending
            on the stream version). If you want control of the format,
            stream the image into a QBuffer (using QImageIO) and stream
            that.
            \endlist
    \row \o QKeySequence
         \o \list
            \o A QList<int>, where each integer is a key in the key sequence
            \endlist
    \row \o QLinkedList<T>
         \o \list
            \o The number of items (quint32)
            \o The items (T)
            \endlist
    \row \o QList<T>
         \o \list
            \o The number of items (quint32)
            \o The items (T)
            \endlist
    \row \o QMap<Key, T>
         \o \list
            \o The number of items (quint32)
            \o For all items, the key (Key) and value (T)
            \endlist
    \row \o QMatrix
         \o \list
            \o m11 (double)
            \o m12 (double)
            \o m21 (double)
            \o m22 (double)
            \o dx (double)
            \o dy (double)
            \endlist
    \row \o QMatrix4x4
         \o \list
            \o m11 (double)
            \o m12 (double)
            \o m13 (double)
            \o m14 (double)
            \o m21 (double)
            \o m22 (double)
            \o m23 (double)
            \o m24 (double)
            \o m31 (double)
            \o m32 (double)
            \o m33 (double)
            \o m34 (double)
            \o m41 (double)
            \o m42 (double)
            \o m43 (double)
            \o m44 (double)
            \endlist
    \row \o QPair<T1, T2>
         \o \list
            \o first (T1)
            \o second (T2)
            \endlist
    \row \o QPalette
         \o The disabled, active, and inactive color groups, each of which consists
            of the following:
            \list
            \o foreground (QBrush)
            \o button (QBrush)
            \o light (QBrush)
            \o midlight (QBrush)
            \o dark (QBrush)
            \o mid (QBrush)
            \o text (QBrush)
            \o brightText (QBrush)
            \o buttonText (QBrush)
            \o base (QBrush)
            \o background (QBrush)
            \o shadow (QBrush)
            \o highlight (QBrush)
            \o highlightedText (QBrush)
            \o link (QBrush)
            \o linkVisited (QBrush)
            \endlist
    \row \o QPen
         \o \list
            \o The pen styles (quint8)
            \o The pen width (quint16)
            \o The pen color (QColor)
            \endlist
    \row \o QPicture
         \o \list
            \o The size of the picture data (quint32)
            \o The raw bytes of picture data (char)
            \endlist
    \row \o QPixmap
         \o \list
            \o Save it as a PNG image.
            \endlist
    \row \o QPoint
         \o \list
            \o The x coordinate (qint32)
            \o The y coordinate (qint32)
            \endlist
    \row \o QQuaternion
         \o \list
            \o The scalar component (double)
            \o The x coordinate (double)
            \o The y coordinate (double)
            \o The z coordinate (double)
            \endlist
    \row \o QRect
         \o \list
            \o left (qint32)
            \o top (qint32)
            \o right (qint32)
            \o bottom (qint32)
            \endlist
    \row \o QRegExp
         \o \list
            \o The regexp pattern (QString)
            \o Case sensitivity (quint8)
            \o Regular expression syntax (quint8)
            \o Minimal matching (quint8)
            \endlist
    \row \o QRegion
         \o \list
            \o The size of the data, i.e. 8 + 16 * (number of rectangles) (quint32)
            \o 10 (qint32)
            \o The number of rectangles (quint32)
            \o The rectangles in sequential order (QRect)
            \endlist
    \row \o QSize
         \o \list
            \o width (qint32)
            \o height (qint32)
            \endlist
    \row \o QString
         \o \list
            \o If the string is null: 0xFFFFFFFF (quint32)
            \o Otherwise: The string length in bytes (quint32) followed by the data in UTF-16
            \endlist
    \row \o QTime
         \o \list
            \o Milliseconds since midnight (quint32)
            \endlist
    \row \o QTransform
         \o \list
            \o m11 (double)
            \o m12 (double)
            \o m13 (double)
            \o m21 (double)
            \o m22 (double)
            \o m23 (double)
            \o m31 (double)
            \o m32 (double)
            \o m33 (double)
            \endlist
    \row \o QUrl
         \o \list
            \o Holds an URL (QString)
            \endlist
    \row \o QVariant
         \o \list
            \o The type of the data (quint32)
            \o The null flag (qint8)
            \o The data of the specified type
            \endlist
    \row \o QVector2D
         \o \list
            \o the x coordinate (double)
            \o the y coordinate (double)
            \endlist
    \row \o QVector3D
         \o \list
            \o the x coordinate (double)
            \o the y coordinate (double)
            \o the z coordinate (double)
            \endlist
    \row \o QVector4D
         \o \list
            \o the x coordinate (double)
            \o the y coordinate (double)
            \o the z coordinate (double)
            \o the w coordinate (double)
            \endlist
    \row \o QVector<T>
         \o \list
            \o The number of items (quint32)
            \o The items (T)
            \endlist
    \endtable
*/