1QPicture(3qt) QPicture(3qt)
2
6 QPicture - Paint device that records and replays QPainter commands
7
9 #include <qpicture.h>
10 Inherits QPaintDevice.
12 Public Members
14 QPicture ( int formatVersion = -1 )
15 QPicture ( const QPicture & pic )
16 ~QPicture ()
17 bool isNull () const
18 uint size () const
19 const char * data () const
20 virtual void setData ( const char * data, uint size )
21 bool play ( QPainter * painter )
22 bool load ( QIODevice * dev, const char * format = 0 )
23 bool load ( const QString & fileName, const char * format = 0 )
24 bool save ( QIODevice * dev, const char * format = 0 )
25 bool save ( const QString & fileName, const char * format = 0 )
26 QRect boundingRect () const
27 void setBoundingRect ( const QRect & r )
28 QPicture & operator= ( const QPicture & p )
29 Protected Members
31 virtual int metric ( int m ) const
32 void detach ()
33 QPicture copy () const
34
36 QDataStream & operator<< ( QDataStream & s, const QPicture & r )
37 QDataStream & operator>> ( QDataStream & s, QPicture & r )
38
40 The QPicture class is a paint device that records and replays QPainter
41 commands.
42 A picture serializes painter commands to an IO device in a platform-
44 independent format. For example, a picture created under Windows can be
45 read on a Sun SPARC.
46 Pictures are called meta-files on some platforms.
48 Qt pictures use a proprietary binary format. Unlike native picture
50 (meta-file) formats on many window systems, Qt pictures have no
51 limitations regarding their contents. Everything that can be painted
52 can also be stored in a picture, e.g. fonts, pixmaps, regions,
53 transformed graphics, etc.
54 QPicture is an implicitly shared class.
56 Example of how to record a picture:
58 QPicture pic;
60 QPainter p;
61 p.begin( &pic ); // paint in picture
62 p.drawEllipse( 10,20, 80,70 ); // draw an ellipse
63 p.end(); // painting done
64 pic.save( "drawing.pic" ); // save picture
65 Example of how to replay a picture:
67 QPicture pic;
69 pic.load( "drawing.pic" ); // load picture
70 QPainter p;
71 p.begin( &myWidget ); // paint in myWidget
72 p.drawPicture( pic ); // draw the picture
73 p.end(); // painting done
74 Pictures can also be drawn using play(). Some basic data about a
76 picture is available, for example, size(), isNull() and boundingRect().
77 See also Graphics Classes, Image Processing Classes, and Implicitly and
79 Explicitly Shared Classes.
80
83 Constructs an empty picture.
84 The formatVersion parameter may be used to create a QPicture that can
86 be read by applications that are compiled with earlier versions of Qt.
87 formatVersion == 1 is binary compatible with Qt 1.x and later.
89 formatVersion == 2 is binary compatible with Qt 2.0.x and later.
91 formatVersion == 3 is binary compatible with Qt 2.1.x and later.
93 formatVersion == 4 is binary compatible with Qt 3.0.x and later.
95 formatVersion == 5 is binary compatible with Qt 3.1.
97 Note that the default formatVersion is -1 which signifies the current
99 release, i.e. for Qt 3.1 a formatVersion of 5 is the same as the
100 default formatVersion of -1.
101 Reading pictures generated by earlier versions of Qt is supported and
103 needs no special coding; the format is automatically detected.
104
106 Constructs a shallow copy of pic.
107
109 Destroys the picture.
110
112 Returns the picture's bounding rectangle or an invalid rectangle if the
113 picture contains no data.
114
116 Returns a deep copy of the picture.
117
119 Returns a pointer to the picture data. The pointer is only valid until
120 the next non-const function is called on this picture. The returned
121 pointer is 0 if the picture contains no data.
122 See also size() and isNull().
124
126 Detaches from shared picture data and makes sure that this picture is
127 the only one referring to the data.
128 If multiple pictures share common data, this picture makes a copy of
130 the data and detaches itself from the sharing mechanism. Nothing is
131 done if there is just a single reference.
132
134 Returns TRUE if the picture contains no data; otherwise returns FALSE.
135
137 Loads a picture from the file specified by fileName and returns TRUE if
138 successful; otherwise returns FALSE.
139 By default, the file will be interpreted as being in the native
141 QPicture format. Specifying the format string is optional and is only
142 needed for importing picture data stored in a different format.
143 Currently, the only external format supported is the W3C SVG format
145 which requires the Qt XML module. The corresponding format string is
146 "svg".
147 See also save().
149 Examples:
151
153 This is an overloaded member function, provided for convenience. It
154 behaves essentially like the above function.
155 dev is the device to use for loading.
157
159 Internal implementation of the virtual QPaintDevice::metric() function.
160 Use the QPaintDeviceMetrics class instead.
162 A picture has the following hard-coded values: dpi=72,
164 numcolors=16777216 and depth=24.
165 m is the metric to get.
167
169 Assigns a shallow copy of p to this picture and returns a reference to
170 this picture.
171
173 Replays the picture using painter, and returns TRUE if successful;
174 otherwise returns FALSE.
175 This function does exactly the same as QPainter::drawPicture() with (x,
177 y) = (0, 0).
178
180 Saves a picture to the file specified by fileName and returns TRUE if
181 successful; otherwise returns FALSE.
182 Specifying the file format string is optional. It's not recommended
184 unless you intend to export the picture data for use by a third party
185 reader. By default the data will be saved in the native QPicture file
186 format.
187 Currently, the only external format supported is the W3C SVG format
189 which requires the Qt XML module. The corresponding format string is
190 "svg".
191 See also load().
193 Example: picture/picture.cpp.
195
197 This is an overloaded member function, provided for convenience. It
198 behaves essentially like the above function.
199 dev is the device to use for saving.
201
203 Sets the picture's bounding rectangle to r. The automatically
204 calculated value is overriden.
205
207 Sets the picture data directly from data and size. This function copies
208 the input data.
209 See also data() and size().
211
213 Returns the size of the picture data.
214 See also data().
216
219 Writes picture r to the stream s and returns a reference to the stream.
220
222 Reads a picture from the stream s into picture r and returns a
223 reference to the stream.
224
227 http://doc.trolltech.com/qpicture.html
228 http://www.trolltech.com/faq/tech.html
229
231 Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the
232 license file included in the distribution for a complete license
233 statement.
234
236 Generated automatically from the source code.
237
239 If you find a bug in Qt, please report it as described in
240 http://doc.trolltech.com/bughowto.html. Good bug reports help us to
241 help you. Thank you.
242 The definitive Qt documentation is provided in HTML format; it is
244 located at $QTDIR/doc/html and can be read using Qt Assistant or with a
245 web browser. This man page is provided as a convenience for those users
246 who prefer man pages, although this format is not officially supported
247 by Trolltech.
248 If you find errors in this manual page, please report them to qt-
250 bugs@trolltech.com. Please include the name of the manual page
251 (qpicture.3qt) and the Qt version (3.3.8).
252Trolltech AS 2 February 2007 QPicture(3qt)