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The QPaintDeviceMetrics class provides information about a paint device. More...
#include <qpaintdevicemetrics.h>
Sometimes when drawing graphics it is necessary to obtain information about the physical characteristics of a paint device. This class provides just that. For example, to compute the aspect ratio of a paint device:
QPaintDeviceMetrics pdm( myWidget ); double aspect = (double)pdm.widthMM() / (double)pdm.heightMM();
QPaintDeviceMetrics contains methods to provide the width and height of a device in both pixels and millimeters, the number of colors the device supports, the number of bit planes, and finally the resolution of the device.
Note that it is not always possible for QPaintDeviceMetrics to compute the values you ask for, particularly for external devices. The ultimate example is asking for the resolution of of a QPrinter that is set to "print to file": who knows what printer that file will end up on?
Returns the height of the paint device in default coordinate system units (e.g., pixels for QPixmap and QWidget).
Examples: action/application.cpp, application/application.cpp, helpviewer/helpwindow.cpp, mdi/application.cpp and qwerty/qwerty.cpp.
Returns the horizontal resolution of the device in dots per inch, which is used when computing font sizes. For X, this is usually the same as could be computed from widthMM(), but it varies on Windows.
Examples: helpviewer/helpwindow.cpp and qwerty/qwerty.cpp.
Returns the vertical resolution of the device in dots per inch, which is used when computing font sizes. For X, this is usually the same as could be computed from heightMM(), but it varies on Windows.
Example: helpviewer/helpwindow.cpp.
Returns the width of the paint device in default coordinate system units (e.g., pixels for QPixmap and QWidget).
Examples: action/application.cpp, application/application.cpp, helpviewer/helpwindow.cpp, mdi/application.cpp and qwerty/qwerty.cpp.
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Copyright © 2001 Trolltech | Trademarks | Qt version 3.0.0-beta1-beta1
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