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152 lines
4.8 KiB
152 lines
4.8 KiB
/****************************************************************************
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**
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** Implementation of QPaintDeviceMetrics class
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**
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** Created : 941109
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**
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** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
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**
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** This file is part of the kernel module of the Qt GUI Toolkit.
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**
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** This file may be used under the terms of the GNU General
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** Public License versions 2.0 or 3.0 as published by the Free
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** Software Foundation and appearing in the files LICENSE.GPL2
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** and LICENSE.GPL3 included in the packaging of this file.
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** Alternatively you may (at your option) use any later version
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** of the GNU General Public License if such license has been
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** publicly approved by Trolltech ASA (or its successors, if any)
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** and the KDE Free Qt Foundation.
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**
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** Please review the following information to ensure GNU General
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** Public Licensing requirements will be met:
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** http://trolltech.com/products/qt/licenses/licensing/opensource/.
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** If you are unsure which license is appropriate for your use, please
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** review the following information:
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** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
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** or contact the sales department at sales@trolltech.com.
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**
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** This file may be used under the terms of the Q Public License as
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** defined by Trolltech ASA and appearing in the file LICENSE.QPL
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** included in the packaging of this file. Licensees holding valid Qt
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** Commercial licenses may use this file in accordance with the Qt
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** Commercial License Agreement provided with the Software.
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**
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** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
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** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
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** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
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** herein.
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**
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**********************************************************************/
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#include "qpaintdevicemetrics.h"
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/*!
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\class QPaintDeviceMetrics qpaintdevicemetrics.h
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\brief The QPaintDeviceMetrics class provides information about a
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paint device.
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\ingroup graphics
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\ingroup images
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Sometimes when drawing graphics it is necessary to obtain
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information about the physical characteristics of a paint device.
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This class provides the information. For example, to compute the
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aspect ratio of a paint device:
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\code
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QPaintDeviceMetrics pdm( myWidget );
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double aspect = (double)pdm.widthMM() / (double)pdm.heightMM();
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\endcode
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QPaintDeviceMetrics contains methods to provide the width and
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height of a device in both pixels (width() and height()) and
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millimeters (widthMM() and heightMM()), the number of colors the
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device supports (numColors()), the number of bit planes (depth()),
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and the resolution of the device (logicalDpiX() and
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logicalDpiY()).
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It is not always possible for QPaintDeviceMetrics to compute the
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values you ask for, particularly for external devices. The
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ultimate example is asking for the resolution of of a QPrinter
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that is set to "print to file": who knows what printer that file
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will end up on?
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*/
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/*!
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Constructs a metric for the paint device \a pd.
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*/
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QPaintDeviceMetrics::QPaintDeviceMetrics( const QPaintDevice *pd )
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{
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pdev = (QPaintDevice *)pd;
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}
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/*!
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\fn int QPaintDeviceMetrics::width() const
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Returns the width of the paint device in default coordinate system
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units (e.g. pixels for QPixmap and QWidget).
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*/
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/*!
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\fn int QPaintDeviceMetrics::height() const
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Returns the height of the paint device in default coordinate
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system units (e.g. pixels for QPixmap and QWidget).
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*/
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/*!
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\fn int QPaintDeviceMetrics::widthMM() const
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Returns the width of the paint device, measured in millimeters.
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*/
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/*!
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\fn int QPaintDeviceMetrics::heightMM() const
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Returns the height of the paint device, measured in millimeters.
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*/
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/*!
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\fn int QPaintDeviceMetrics::numColors() const
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Returns the number of different colors available for the paint
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device. Since this value is an int will not be sufficient to represent
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the number of colors on 32 bit displays, in which case INT_MAX is
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returned instead.
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*/
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/*!
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\fn int QPaintDeviceMetrics::depth() const
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Returns the bit depth (number of bit planes) of the paint device.
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*/
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/*!
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\fn int QPaintDeviceMetrics::logicalDpiX() const
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Returns the horizontal resolution of the device in dots per inch,
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which is used when computing font sizes. For X, this is usually
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the same as could be computed from widthMM(), but it varies on
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Windows.
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*/
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/*!
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\fn int QPaintDeviceMetrics::logicalDpiY() const
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Returns the vertical resolution of the device in dots per inch,
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which is used when computing font sizes. For X, this is usually
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the same as could be computed from heightMM(), but it varies on
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Windows.
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*/
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/*!
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\fn int QPaintDeviceMetrics::physicalDpiX() const
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\internal
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*/
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/*!
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\fn int QPaintDeviceMetrics::physicalDpiY() const
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\internal
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*/
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