/src/qtbase/src/gui/painting/qpaintdevice.cpp

Source
// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

#include "qpaintdevice.h"

QT_BEGIN_NAMESPACE

QPaintDevice::QPaintDevice() noexcept
{
    painters = 0;
}

QPaintDevice::~QPaintDevice()
{
    if (paintingActive())
        qWarning("QPaintDevice: Cannot destroy paint device that is being "
                  "painted");
}

/*!
    \internal
*/
// ### Qt 7: Replace this workaround mechanism: virtual devicePixelRatio() and virtual metricF()
double QPaintDevice::getDecodedMetricF(PaintDeviceMetric metricA, PaintDeviceMetric metricB) const
{
    qint32 buf[2];
    // The Encoded metric enum values come in pairs of one odd and one even value.
    // We map those to the 0 and 1 indexes of buf by taking just the least significant bit.
    // Same mapping here as in the encodeMetricF() function, to ensure correct order.
    buf[metricA & 1] = metric(metricA);
    buf[metricB & 1] = metric(metricB);
    double res;
    memcpy(&res, buf, sizeof(res));
    return res;
}

qreal QPaintDevice::devicePixelRatio() const
{
    Q_STATIC_ASSERT((PdmDevicePixelRatioF_EncodedA & 1) != (PdmDevicePixelRatioF_EncodedB & 1));
    double res;
    int scaledDpr = metric(PdmDevicePixelRatioScaled);
    if (scaledDpr == int(devicePixelRatioFScale())) {
        res = 1; // Shortcut for common case
    } else if (scaledDpr == 2 * int(devicePixelRatioFScale())) {
        res = 2; // Shortcut for common case
    } else {
        res = getDecodedMetricF(PdmDevicePixelRatioF_EncodedA, PdmDevicePixelRatioF_EncodedB);
        if (res <= 0) // These metrics not implemented, fall back to PdmDevicePixelRatioScaled
            res = scaledDpr / devicePixelRatioFScale();
    }
    return res;
}

/*!
    \internal
*/
void QPaintDevice::initPainter(QPainter *) const
{
}

/*!
    \internal
*/
QPaintDevice *QPaintDevice::redirected(QPoint *) const
{
    return nullptr;
}

/*!
    \internal
*/
QPainter *QPaintDevice::sharedPainter() const
{
    return nullptr;
}

Q_GUI_EXPORT int qt_paint_device_metric(const QPaintDevice *device, QPaintDevice::PaintDeviceMetric metric)
{
    return device->metric(metric);
}

int QPaintDevice::metric(PaintDeviceMetric m) const
{
    // Fallback: A subclass has not implemented PdmDevicePixelRatioScaled but might
    // have implemented PdmDevicePixelRatio.
    if (m == PdmDevicePixelRatioScaled)
        return this->metric(PdmDevicePixelRatio) * devicePixelRatioFScale();
    if (m == PdmNumColors)
        return 0;
    if (m == PdmDevicePixelRatio)
        return 1;

    qWarning("QPaintDevice::metrics: Device has no metric information");

    switch (m) {
    case PdmDevicePixelRatioScaled:
    case PdmDevicePixelRatio:
    case PdmNumColors:
        Q_UNREACHABLE();
        break;
    case PdmDpiX:
    case PdmDpiY:
        return 72;
    case PdmDevicePixelRatioF_EncodedA:
    case PdmDevicePixelRatioF_EncodedB:
        return 0;
    case PdmWidth:
    case PdmHeight:
    case PdmWidthMM:
    case PdmHeightMM:
    case PdmDepth:
    case PdmPhysicalDpiX:
    case PdmPhysicalDpiY:
        return 0;
    }
    qDebug("Unrecognized metric %d!", m);
    return 0;
}

QT_END_NAMESPACE

Line	Count	Source
1		// Copyright (C) 2016 The Qt Company Ltd.
2		// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4		#include "qpaintdevice.h"
5
6		QT_BEGIN_NAMESPACE
7
8		QPaintDevice::QPaintDevice() noexcept
9	357M	{
10	357M	painters = 0;
11	357M	}
12
13		QPaintDevice::~QPaintDevice()
14	357M	{
15	357M	if (paintingActive())
16	357M	qWarning("QPaintDevice: Cannot destroy paint device that is being "
17	0	"painted");
18	357M	}
19
20		/*!
21		\internal
22		*/
23		// ### Qt 7: Replace this workaround mechanism: virtual devicePixelRatio() and virtual metricF()
24		double QPaintDevice::getDecodedMetricF(PaintDeviceMetric metricA, PaintDeviceMetric metricB) const
25	0	{
26	0	qint32 buf[2];
27		// The Encoded metric enum values come in pairs of one odd and one even value.
28		// We map those to the 0 and 1 indexes of buf by taking just the least significant bit.
29		// Same mapping here as in the encodeMetricF() function, to ensure correct order.
30	0	buf[metricA & 1] = metric(metricA);
31	0	buf[metricB & 1] = metric(metricB);
32	0	double res;
33	0	memcpy(&res, buf, sizeof(res));
34	0	return res;
35	0	}
36
37		qreal QPaintDevice::devicePixelRatio() const
38	127k	{
39	127k	Q_STATIC_ASSERT((PdmDevicePixelRatioF_EncodedA & 1) != (PdmDevicePixelRatioF_EncodedB & 1));
40	127k	double res;
41	127k	int scaledDpr = metric(PdmDevicePixelRatioScaled);
42	127k	if (scaledDpr == int(devicePixelRatioFScale())) {
43	127k	res = 1; // Shortcut for common case
44	127k	} else if (scaledDpr == 2 * int(devicePixelRatioFScale())) {
45	0	res = 2; // Shortcut for common case
46	0	} else {
47	0	res = getDecodedMetricF(PdmDevicePixelRatioF_EncodedA, PdmDevicePixelRatioF_EncodedB);
48	0	if (res <= 0) // These metrics not implemented, fall back to PdmDevicePixelRatioScaled
49	0	res = scaledDpr / devicePixelRatioFScale();
50	0	}
51	127k	return res;
52	127k	}
53
54		/*!
55		\internal
56		*/
57		void QPaintDevice::initPainter(QPainter *) const
58	106k	{
59	106k	}
60
61		/*!
62		\internal
63		*/
64		QPaintDevice QPaintDevice::redirected(QPoint ) const
65	106k	{
66	106k	return nullptr;
67	106k	}
68
69		/*!
70		\internal
71		*/
72		QPainter *QPaintDevice::sharedPainter() const
73	213k	{
74	213k	return nullptr;
75	213k	}
76
77		Q_GUI_EXPORT int qt_paint_device_metric(const QPaintDevice *device, QPaintDevice::PaintDeviceMetric metric)
78	0	{
79	0	return device->metric(metric);
80	0	}
81
82		int QPaintDevice::metric(PaintDeviceMetric m) const
83	0	{
84		// Fallback: A subclass has not implemented PdmDevicePixelRatioScaled but might
85		// have implemented PdmDevicePixelRatio.
86	0	if (m == PdmDevicePixelRatioScaled)
87	0	return this->metric(PdmDevicePixelRatio) * devicePixelRatioFScale();
88	0	if (m == PdmNumColors)
89	0	return 0;
90	0	if (m == PdmDevicePixelRatio)
91	0	return 1;
92
93	0	qWarning("QPaintDevice::metrics: Device has no metric information");
94
95	0	switch (m) {
96	0	case PdmDevicePixelRatioScaled:
97	0	case PdmDevicePixelRatio:
98	0	case PdmNumColors:
99	0	Q_UNREACHABLE();
100	0	break;
101	0	case PdmDpiX:
102	0	case PdmDpiY:
103	0	return 72;
104	0	case PdmDevicePixelRatioF_EncodedA:
105	0	case PdmDevicePixelRatioF_EncodedB:
106	0	return 0;
107	0	case PdmWidth:
108	0	case PdmHeight:
109	0	case PdmWidthMM:
110	0	case PdmHeightMM:
111	0	case PdmDepth:
112	0	case PdmPhysicalDpiX:
113	0	case PdmPhysicalDpiY:
114	0	return 0;
115	0	}
116	0	qDebug("Unrecognized metric %d!", m);
117	0	return 0;
118	0	}
119
120		QT_END_NAMESPACE

Coverage Report

Created: 2026-01-25 07:18