/src/qtbase/src/gui/image/qiconengine.cpp
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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 | | // Qt-Security score:significant reason:default |
4 | | |
5 | | #include "qiconengine.h" |
6 | | #include "qiconengine_p.h" |
7 | | #include "qpainter.h" |
8 | | |
9 | | QT_BEGIN_NAMESPACE |
10 | | |
11 | | /*! |
12 | | \class QIconEngine |
13 | | |
14 | | \brief The QIconEngine class provides an abstract base class for QIcon renderers. |
15 | | |
16 | | \ingroup painting |
17 | | \inmodule QtGui |
18 | | |
19 | | An icon engine provides the rendering functions for a QIcon. Each icon has a |
20 | | corresponding icon engine that is responsible for drawing the icon with a |
21 | | requested size, mode and state. |
22 | | |
23 | | The icon is rendered by the paint() function, and the icon can additionally be |
24 | | obtained as a pixmap with the pixmap() function (the default implementation |
25 | | simply uses paint() to achieve this). The addPixmap() function can be used to |
26 | | add new pixmaps to the icon engine, and is used by QIcon to add specialized |
27 | | custom pixmaps. |
28 | | |
29 | | The paint(), pixmap(), and addPixmap() functions are all virtual, and can |
30 | | therefore be reimplemented in subclasses of QIconEngine. |
31 | | |
32 | | \sa QIconEnginePlugin |
33 | | |
34 | | */ |
35 | | |
36 | | /*! |
37 | | \fn virtual void QIconEngine::paint(QPainter *painter, const QRect &rect, QIcon::Mode mode, QIcon::State state) = 0; |
38 | | |
39 | | Uses the given \a painter to paint the icon with the required \a mode and |
40 | | \a state into the rectangle \a rect. |
41 | | */ |
42 | | |
43 | | /*! Returns the actual size of the icon the engine provides for the |
44 | | requested \a size, \a mode and \a state. The default implementation |
45 | | returns the given \a size. |
46 | | |
47 | | The returned size is in device-independent pixels (This |
48 | | is relevant for high-dpi pixmaps). |
49 | | */ |
50 | | QSize QIconEngine::actualSize(const QSize &size, QIcon::Mode /*mode*/, QIcon::State /*state*/) |
51 | 0 | { |
52 | 0 | return size; |
53 | 0 | } |
54 | | |
55 | | /*! |
56 | | \since 5.6 |
57 | | Constructs the icon engine. |
58 | | */ |
59 | | QIconEngine::QIconEngine() |
60 | 0 | { |
61 | 0 | } |
62 | | |
63 | | /*! |
64 | | \since 5.8 |
65 | | \internal |
66 | | */ |
67 | | QIconEngine::QIconEngine(const QIconEngine &) |
68 | 0 | { |
69 | 0 | } |
70 | | |
71 | | /*! |
72 | | Destroys the icon engine. |
73 | | */ |
74 | | QIconEngine::~QIconEngine() |
75 | 0 | { |
76 | 0 | } |
77 | | |
78 | | |
79 | | /*! |
80 | | Returns the icon as a pixmap with the required \a size, \a mode, |
81 | | and \a state. The default implementation creates a new pixmap and |
82 | | calls paint() to fill it. |
83 | | */ |
84 | | QPixmap QIconEngine::pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state) |
85 | 0 | { |
86 | 0 | QPixmap pm(size); |
87 | 0 | { |
88 | 0 | QPainter p(&pm); |
89 | 0 | paint(&p, QRect(QPoint(0,0),size), mode, state); |
90 | 0 | } |
91 | 0 | return pm; |
92 | 0 | } |
93 | | |
94 | | /*! |
95 | | Called by QIcon::addPixmap(). Adds a specialized \a pixmap for the given |
96 | | \a mode and \a state. The default pixmap-based engine stores any supplied |
97 | | pixmaps, and it uses them instead of scaled pixmaps if the size of a pixmap |
98 | | matches the size of icon requested. Custom icon engines that implement |
99 | | scalable vector formats are free to ignores any extra pixmaps. |
100 | | */ |
101 | | void QIconEngine::addPixmap(const QPixmap &/*pixmap*/, QIcon::Mode /*mode*/, QIcon::State /*state*/) |
102 | 0 | { |
103 | 0 | } |
104 | | |
105 | | |
106 | | /*! Called by QIcon::addFile(). Adds a specialized pixmap from the |
107 | | file with the given \a fileName, \a size, \a mode and \a state. The |
108 | | default pixmap-based engine stores any supplied file names, and it |
109 | | loads the pixmaps on demand instead of using scaled pixmaps if the |
110 | | size of a pixmap matches the size of icon requested. Custom icon |
111 | | engines that implement scalable vector formats are free to ignores |
112 | | any extra files. |
113 | | */ |
114 | | void QIconEngine::addFile(const QString &/*fileName*/, const QSize &/*size*/, QIcon::Mode /*mode*/, QIcon::State /*state*/) |
115 | 0 | { |
116 | 0 | } |
117 | | |
118 | | |
119 | | /*! |
120 | | \enum QIconEngine::IconEngineHook |
121 | | |
122 | | These enum values are used for virtual_hook() to allow additional |
123 | | queries to icon engine without breaking binary compatibility. |
124 | | |
125 | | \value IsNullHook Allow to query if this engine represents a null |
126 | | icon. The \a data argument of the virtual_hook() is a pointer to a |
127 | | bool that can be set to true if the icon is null. This enum value |
128 | | was added in Qt 5.7. |
129 | | |
130 | | \value ScaledPixmapHook Provides a way to get a pixmap that is scaled |
131 | | according to the given scale (typically equal to the \l {High |
132 | | DPI}{device pixel ratio}). The \a data argument of the virtual_hook() |
133 | | function is a \l ScaledPixmapArgument pointer that contains both the input and |
134 | | output arguments. This enum value was added in Qt 5.9. |
135 | | |
136 | | \sa virtual_hook() |
137 | | */ |
138 | | |
139 | | /*! |
140 | | \class QIconEngine::ScaledPixmapArgument |
141 | | \since 5.9 |
142 | | |
143 | | \inmodule QtGui |
144 | | |
145 | | This struct represents arguments to the virtual_hook() function when |
146 | | the \a id parameter is QIconEngine::ScaledPixmapHook. |
147 | | |
148 | | The struct provides a way for icons created via \l QIcon::fromTheme() |
149 | | to return pixmaps that are designed for the current \l {High |
150 | | DPI}{device pixel ratio}. The scale for such an icon is specified |
151 | | using the \l {Icon Theme Specification - Directory Layout}{Scale directory key} |
152 | | in the appropriate \c index.theme file. |
153 | | |
154 | | Icons created via other approaches will return the same result as a call to |
155 | | \l pixmap() would, and continue to benefit from Qt's \l {High Resolution |
156 | | Versions of Images}{"@nx" high DPI syntax}. |
157 | | |
158 | | \sa virtual_hook(), QIconEngine::IconEngineHook, {High DPI Icons} |
159 | | */ |
160 | | |
161 | | /*! |
162 | | \variable QIconEngine::ScaledPixmapArgument::size |
163 | | \brief The requested size of the pixmap. |
164 | | */ |
165 | | |
166 | | /*! |
167 | | \variable QIconEngine::ScaledPixmapArgument::mode |
168 | | \brief The requested mode of the pixmap. |
169 | | |
170 | | \sa QIcon::Mode |
171 | | */ |
172 | | |
173 | | /*! |
174 | | \variable QIconEngine::ScaledPixmapArgument::state |
175 | | \brief The requested state of the pixmap. |
176 | | |
177 | | \sa QIcon::State |
178 | | */ |
179 | | |
180 | | /*! |
181 | | \variable QIconEngine::ScaledPixmapArgument::scale |
182 | | \brief The requested scale of the pixmap. |
183 | | */ |
184 | | |
185 | | /*! |
186 | | \variable QIconEngine::ScaledPixmapArgument::pixmap |
187 | | |
188 | | \brief The pixmap that is the best match for the given \l size, \l mode, \l |
189 | | state, and \l scale. This is an output parameter that is set after calling |
190 | | \l virtual_hook(). |
191 | | */ |
192 | | |
193 | | |
194 | | /*! |
195 | | Returns a key that identifies this icon engine. |
196 | | */ |
197 | | QString QIconEngine::key() const |
198 | 0 | { |
199 | 0 | return QString(); |
200 | 0 | } |
201 | | |
202 | | /*! \fn QIconEngine *QIconEngine::clone() const |
203 | | |
204 | | Reimplement this method to return a clone of this icon engine. |
205 | | */ |
206 | | |
207 | | /*! |
208 | | Reads icon engine contents from the QDataStream \a in. Returns |
209 | | true if the contents were read; otherwise returns \c false. |
210 | | |
211 | | QIconEngine's default implementation always return false. |
212 | | */ |
213 | | bool QIconEngine::read(QDataStream &) |
214 | 0 | { |
215 | 0 | return false; |
216 | 0 | } |
217 | | |
218 | | /*! |
219 | | Writes the contents of this engine to the QDataStream \a out. |
220 | | Returns \c true if the contents were written; otherwise returns \c false. |
221 | | |
222 | | QIconEngine's default implementation always return false. |
223 | | */ |
224 | | bool QIconEngine::write(QDataStream &) const |
225 | 0 | { |
226 | 0 | return false; |
227 | 0 | } |
228 | | |
229 | | /*! |
230 | | Additional method to allow extending QIconEngine without |
231 | | adding new virtual methods (and without breaking binary compatibility). |
232 | | The actual action and format of \a data depends on \a id argument |
233 | | which is in fact a constant from IconEngineHook enum. |
234 | | |
235 | | \sa IconEngineHook |
236 | | */ |
237 | | void QIconEngine::virtual_hook(int id, void *data) |
238 | 0 | { |
239 | 0 | switch (id) { |
240 | 0 | case QIconEngine::ScaledPixmapHook: { |
241 | 0 | QIconEngine::ScaledPixmapArgument &arg = |
242 | 0 | *reinterpret_cast<QIconEngine::ScaledPixmapArgument*>(data); |
243 | | // try to get a pixmap with the correct size, the dpr is adjusted later on |
244 | 0 | arg.pixmap = pixmap(arg.size * arg.scale, arg.mode, arg.state); |
245 | 0 | break; |
246 | 0 | } |
247 | 0 | default: |
248 | 0 | break; |
249 | 0 | } |
250 | 0 | } |
251 | | |
252 | | /*! |
253 | | Returns sizes of all images that are contained in the engine for the |
254 | | specific \a mode and \a state. |
255 | | */ |
256 | | QList<QSize> QIconEngine::availableSizes(QIcon::Mode /*mode*/, QIcon::State /*state*/) |
257 | 0 | { |
258 | 0 | return {}; |
259 | 0 | } |
260 | | |
261 | | /*! |
262 | | Returns the name used to create the engine, if available. |
263 | | */ |
264 | | QString QIconEngine::iconName() |
265 | 0 | { |
266 | 0 | return QString(); |
267 | 0 | } |
268 | | |
269 | | /*! |
270 | | \since 5.7 |
271 | | |
272 | | Returns true if this icon engine represent a null QIcon. |
273 | | |
274 | | \include qiconengine-virtualhookhelper.qdocinc |
275 | | */ |
276 | | bool QIconEngine::isNull() |
277 | 0 | { |
278 | 0 | bool isNull = false; |
279 | 0 | virtual_hook(QIconEngine::IsNullHook, &isNull); |
280 | 0 | return isNull; |
281 | 0 | } |
282 | | |
283 | | /*! |
284 | | \since 5.9 |
285 | | |
286 | | Returns a pixmap for the given \a size, \a mode, \a state and \a scale. |
287 | | |
288 | | The \a scale argument is typically equal to the \l {High DPI} |
289 | | {device pixel ratio} of the display. The size is given in device-independent pixels. |
290 | | |
291 | | \include qiconengine-virtualhookhelper.qdocinc |
292 | | |
293 | | \note Some engines may cast \a scale to an integer. |
294 | | |
295 | | \sa ScaledPixmapArgument |
296 | | */ |
297 | | QPixmap QIconEngine::scaledPixmap(const QSize &size, QIcon::Mode mode, QIcon::State state, qreal scale) |
298 | 0 | { |
299 | 0 | ScaledPixmapArgument arg; |
300 | 0 | arg.size = size; |
301 | 0 | arg.mode = mode; |
302 | 0 | arg.state = state; |
303 | 0 | arg.scale = scale; |
304 | 0 | const_cast<QIconEngine *>(this)->virtual_hook(QIconEngine::ScaledPixmapHook, reinterpret_cast<void*>(&arg)); |
305 | 0 | return arg.pixmap; |
306 | 0 | } |
307 | | |
308 | | |
309 | | // ------- QProxyIconEngine ----- |
310 | | |
311 | | void QProxyIconEngine::paint(QPainter *painter, const QRect &rect, QIcon::Mode mode, QIcon::State state) |
312 | 0 | { |
313 | 0 | proxiedEngine()->paint(painter, rect, mode, state); |
314 | 0 | } |
315 | | |
316 | | QSize QProxyIconEngine::actualSize(const QSize &size, QIcon::Mode mode, QIcon::State state) |
317 | 0 | { |
318 | 0 | return proxiedEngine()->actualSize(size, mode, state); |
319 | 0 | } |
320 | | |
321 | | QPixmap QProxyIconEngine::pixmap(const QSize &size, QIcon::Mode mode, QIcon::State state) |
322 | 0 | { |
323 | 0 | return proxiedEngine()->pixmap(size, mode, state); |
324 | 0 | } |
325 | | |
326 | | void QProxyIconEngine::addPixmap(const QPixmap &pixmap, QIcon::Mode mode, QIcon::State state) |
327 | 0 | { |
328 | 0 | proxiedEngine()->addPixmap(pixmap, mode, state); |
329 | 0 | } |
330 | | |
331 | | void QProxyIconEngine::addFile(const QString &fileName, const QSize &size, QIcon::Mode mode, QIcon::State state) |
332 | 0 | { |
333 | 0 | proxiedEngine()->addFile(fileName, size, mode, state); |
334 | 0 | } |
335 | | |
336 | | QString QProxyIconEngine::key() const |
337 | 0 | { |
338 | 0 | return proxiedEngine()->key(); |
339 | 0 | } |
340 | | |
341 | | QIconEngine *QProxyIconEngine::clone() const |
342 | 0 | { |
343 | 0 | return proxiedEngine()->clone(); |
344 | 0 | } |
345 | | |
346 | | bool QProxyIconEngine::read(QDataStream &in) |
347 | 0 | { |
348 | 0 | return proxiedEngine()->read(in); |
349 | 0 | } |
350 | | |
351 | | bool QProxyIconEngine::write(QDataStream &out) const |
352 | 0 | { |
353 | 0 | return proxiedEngine()->write(out); |
354 | 0 | } |
355 | | |
356 | | QList<QSize> QProxyIconEngine::availableSizes(QIcon::Mode mode, QIcon::State state) |
357 | 0 | { |
358 | 0 | return proxiedEngine()->availableSizes(mode, state); |
359 | 0 | } |
360 | | |
361 | | QString QProxyIconEngine::iconName() |
362 | 0 | { |
363 | 0 | return proxiedEngine()->iconName(); |
364 | 0 | } |
365 | | |
366 | | bool QProxyIconEngine::isNull() |
367 | 0 | { |
368 | 0 | return proxiedEngine()->isNull(); |
369 | 0 | } |
370 | | |
371 | | QPixmap QProxyIconEngine::scaledPixmap(const QSize &size, QIcon::Mode mode, QIcon::State state, qreal scale) |
372 | 0 | { |
373 | 0 | return proxiedEngine()->scaledPixmap(size, mode, state, scale); |
374 | 0 | } |
375 | | |
376 | | void QProxyIconEngine::virtual_hook(int id, void *data) |
377 | 0 | { |
378 | 0 | proxiedEngine()->virtual_hook(id, data); |
379 | 0 | } |
380 | | |
381 | | |
382 | | QT_END_NAMESPACE |