QPaintDeviceMetrics(3qt)QPaintDeviceMetrics(3qt)NAMEQPaintDeviceMetrics - Information about a paint device
#include <qpaintdevicemetrics.h>
Public Members
QPaintDeviceMetrics ( const QPaintDevice * )
enum { PdmWidth = 1, PdmHeight, PdmWidthMM, PdmHeightMM,
PdmNumColors, PdmDepth, PdmDpiX, PdmDpiY }
int width () const
int height () const
int widthMM () const
int heightMM () const
int logicalDpiX () const
int logicalDpiY () const
int numColors () const
int depth () const
DESCRIPTION
The QPaintDeviceMetrics class provides information about a
paint device.
Sometimes it is necessary to obtain information about the
physical characteristics of a paint device when drawing
graphics. 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 a QPrinter that is set to
"print to file" - who knows what printer that file will
end up?.
MEMBER FUNCTION DOCUMENTATIONQPaintDeviceMetrics::QPaintDeviceMetrics ( const QPaintDevice *
pd )
Constructs a metric for the paint device pd.
int QPaintDeviceMetrics::depth () const
Returns the bit depth (number of bit planes) of the paint
device.
int QPaintDeviceMetrics::height () const
Returns the height of the paint device, in default
Trolltech AS 13 June 2001 1
QPaintDeviceMetrics(3qt)QPaintDeviceMetrics(3qt)
coordinate system units (e.g. pixels for QPixmap and
QWidget).
int QPaintDeviceMetrics::heightMM () const
Returns the height of the paint device, measured in
millimeters.
int QPaintDeviceMetrics::logicalDpiX () const
Returns the horizontal resolution of the device, in dots
per inch, that is used when computing font sizes. For X
this is usually the same as could be computed from
widthMM(), but on Windows this varies.
int QPaintDeviceMetrics::logicalDpiY () const
Returns the vertical resolution of the device, in dots per
inch, that is used when computing font sizes. For X this
is usually the same as could be computed from heightMM(),
but on Windows this varies.
int QPaintDeviceMetrics::numColors () const
Returns the number of different colors available for the
paint device.
int QPaintDeviceMetrics::width () const
Returns the width of the paint device, in default
coordinate system units (e.g. pixels for QPixmap and
QWidget).
int QPaintDeviceMetrics::widthMM () const
Returns the width of the paint device, measured in
millimeters.
SEE ALSO
http://doc.trolltech.com/qpaintdevicemetrics.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
If you find a bug in Qt, please report it as described in
http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page
(qpaintdevicemetrics.3qt) and the Qt version (2.3.1).
Trolltech AS 13 June 2001 2
