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The QPicture class is a paint device that records and replays QPainter commands. More...
#include <qpicture.h>
Inherits QPaintDevice.
A picture serializes painter commands to an IO device in a platform-independent format. A picture created under Windows can be read on a Sun SPARC.
Pictures are called meta-files on some platforms.
Qt pictures use a proprietary binary format. Unlike native picture (meta-file) formats on many window systems, Qt pictures have no limitations regarding the contents. Everything that can be painted can also be stored in a picture (fonts, pixmaps, regions, transformed graphics, etc.).
QPicture is an implicitely shared class.
Example of how to record a picture:
QPicture pic; QPainter p; p.begin( &pic ); // paint in picture p.drawEllipse( 10,20, 80,70 ); // draw an ellipse p.end(); // painting done pic.save( "drawing.pic" ); // save picture
Example of how to replay a picture:
QPicture pic; pic.load( "drawing.pic" ); // load picture QPainter p; p.begin( &myWidget ); // paint in myWidget p.drawPicture( pic ); // draw the picture p.end(); // painting done
The formatVersion parameter may be used to create a QPicture that can be read by applications that are compiled with earlier versions of Qt. Currently supported is formatVersion == 1, which will make a QPicture stored in a format that is binary compatible with Qt 1.x, formatVersion == 2 for a format compatible with Qt 2.0.x programs and formatVersion == 3 for Qt 2.1.x and later.
Reading of pictures generated by earlier versions of Qt is supported and needs no special coding; the format is automatically detected.
If multiple pictures share common data, this picture makes a copy of the data and detaches itself from the sharing mechanism. Nothing is done if there is just a single reference.
By default, the file will be interpreted as being of the native QPicture format. Specifying the format string is optional and is only needed for importing picture data stored in a different format.
Currently, the only external format supported is the W3C SVG format which requires the Qt XML module. The corresponding format string is "svg".
See also save().
Examples: picture/picture.cpp and xform/xform.cpp.
Use the QPaintDeviceMetrics class instead.
A picture has the following hard-coded values: dpi = 72, numcolors=16777216 and depth=24.
Reimplemented from QPaintDevice.
This function does exactly the same as QPainter::drawPicture() with (x, y) = (0, 0).
Specifying the file format string is optional. It's not recommended unless you intend to export the picture data for the use in a 3rd party reader. By default the data will be saved in the native QPicture file format.
Currently, the only external format supported is the W3C SVG format which requires the Qt XML module. The corresponding format string is "svg".
See also load().
Example: picture/picture.cpp.
See also data().
Writes a QPicture to the stream and returns a reference to the stream.
Reads a QPicture from the stream and returns a reference to the stream.
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Copyright © 2001 Trolltech | Trademarks | Qt version 3.0.0-beta1-beta1
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