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 | #include "qpaintengine.h" |
4 | #include "qpaintengine_p.h" |
5 | #include "qpainter_p.h" |
6 | #include "qpolygon.h" |
7 | #include "qbitmap.h" |
8 | #include <qdebug.h> |
9 | #include <qmath.h> |
10 | #include <qguiapplication.h> |
11 | #include <qvarlengtharray.h> |
12 | #include <qpa/qplatformintegration.h> |
13 | #include <qpa/qplatformpixmap.h> |
14 | #include <private/qfontengine_p.h> |
15 | #include <private/qguiapplication_p.h> |
16 | #include <private/qpaintengineex_p.h> |
17 | #include <private/qtextengine_p.h> |
18 | |
19 | #include <memory> |
20 | |
21 | QT_BEGIN_NAMESPACE |
22 | |
23 | /*! |
24 | \class QTextItem |
25 | \inmodule QtGui |
26 | |
27 | \brief The QTextItem class provides all the information required to draw |
28 | text in a custom paint engine. |
29 | |
30 | When you reimplement your own paint engine, you must reimplement |
31 | QPaintEngine::drawTextItem(), a function that takes a QTextItem as |
32 | one of its arguments. |
33 | */ |
34 | |
35 | /*! |
36 | \enum QTextItem::RenderFlag |
37 | |
38 | \value RightToLeft Render the text from right to left. |
39 | \value Overline Paint a line above the text. |
40 | \value Underline Paint a line under the text. |
41 | \value StrikeOut Paint a line through the text. |
42 | \omitvalue Dummy |
43 | */ |
44 | |
45 | |
46 | /*! |
47 | \fn qreal QTextItem::descent() const |
48 | |
49 | Corresponds to the \l{QFontMetrics::descent()}{descent} of the piece of text that is drawn. |
50 | */ |
51 | qreal QTextItem::descent() const |
52 | { |
53 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
54 | return ti->descent.toReal(); |
55 | } |
56 | |
57 | /*! |
58 | \fn qreal QTextItem::ascent() const |
59 | |
60 | Corresponds to the \l{QFontMetrics::ascent()}{ascent} of the piece of text that is drawn. |
61 | */ |
62 | qreal QTextItem::ascent() const |
63 | { |
64 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
65 | return ti->ascent.toReal(); |
66 | } |
67 | |
68 | /*! |
69 | \fn qreal QTextItem::width() const |
70 | |
71 | Specifies the total width of the text to be drawn. |
72 | */ |
73 | qreal QTextItem::width() const |
74 | { |
75 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
76 | return ti->width.toReal(); |
77 | } |
78 | |
79 | /*! |
80 | \fn QTextItem::RenderFlags QTextItem::renderFlags() const |
81 | |
82 | Returns the render flags used. |
83 | */ |
84 | QTextItem::RenderFlags QTextItem::renderFlags() const |
85 | { |
86 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
87 | return ti->flags; |
88 | } |
89 | |
90 | /*! |
91 | \fn QString QTextItem::text() const |
92 | |
93 | Returns the text that should be drawn. |
94 | */ |
95 | QString QTextItem::text() const |
96 | { |
97 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
98 | return QString(ti->chars, ti->num_chars); |
99 | } |
100 | |
101 | /*! |
102 | \fn QFont QTextItem::font() const |
103 | |
104 | Returns the font that should be used to draw the text. |
105 | */ |
106 | QFont QTextItem::font() const |
107 | { |
108 | const QTextItemInt *ti = static_cast<const QTextItemInt *>(this); |
109 | return ti->f ? *ti->f : QGuiApplication::font(); |
110 | } |
111 | |
112 | |
113 | /*! |
114 | \class QPaintEngine |
115 | \ingroup painting |
116 | \inmodule QtGui |
117 | |
118 | \brief The QPaintEngine class provides an abstract definition of how |
119 | QPainter draws to a given device on a given platform. |
120 | |
121 | Qt provides several premade implementations of QPaintEngine for the |
122 | different painter backends we support. The primary paint engine |
123 | provided is the raster paint engine, which contains a software |
124 | rasterizer which supports the full feature set on all supported platforms. |
125 | This is the default for painting on QWidget-based classes in e.g. on Windows, |
126 | X11 and \macos, it is the backend for painting on QImage and it is |
127 | used as a fallback for paint engines that do not support a certain |
128 | capability. In addition we provide QPaintEngine implementations for |
129 | OpenGL (accessible through QOpenGLWidget) and printing (which allows using |
130 | QPainter to draw on a QPrinter object). |
131 | |
132 | If one wants to use QPainter to draw to a different backend, |
133 | one must subclass QPaintEngine and reimplement all its virtual |
134 | functions. The QPaintEngine implementation is then made available by |
135 | subclassing QPaintDevice and reimplementing the virtual function |
136 | QPaintDevice::paintEngine(). |
137 | |
138 | QPaintEngine is created and owned by the QPaintDevice that created it. |
139 | |
140 | \sa QPainter, QPaintDevice::paintEngine(), {Paint System} |
141 | */ |
142 | |
143 | /*! |
144 | \enum QPaintEngine::PaintEngineFeature |
145 | |
146 | This enum is used to describe the features or capabilities that the |
147 | paint engine has. If a feature is not supported by the engine, |
148 | QPainter will do a best effort to emulate that feature through other |
149 | means and pass on an alpha blended QImage to the engine with the |
150 | emulated results. Some features cannot be emulated: AlphaBlend and PorterDuff. |
151 | |
152 | \value AlphaBlend The engine can alpha blend primitives. |
153 | \value Antialiasing The engine can use antialiasing to improve the appearance |
154 | of rendered primitives. |
155 | \value BlendModes The engine supports blending modes. |
156 | \value BrushStroke The engine supports drawing strokes that |
157 | contain brushes as fills, not just solid |
158 | colors (e.g. a dashed gradient line of |
159 | width 2). |
160 | \value ConicalGradientFill The engine supports conical gradient fills. |
161 | \value ConstantOpacity The engine supports the feature provided by |
162 | QPainter::setOpacity(). |
163 | \value LinearGradientFill The engine supports linear gradient fills. |
164 | \value MaskedBrush The engine is capable of rendering brushes that has a |
165 | texture with an alpha channel or a mask. |
166 | \value ObjectBoundingModeGradients The engine has native support for gradients |
167 | with coordinate mode QGradient::ObjectBoundingMode. |
168 | Otherwise, if QPaintEngine::PatternTransform is |
169 | supported, object bounding mode gradients are |
170 | converted to gradients with coordinate mode |
171 | QGradient::LogicalMode and a brush transform for |
172 | the coordinate mapping. |
173 | \value PainterPaths The engine has path support. |
174 | \value PaintOutsidePaintEvent The engine is capable of painting outside of |
175 | paint events. |
176 | \value PatternBrush The engine is capable of rendering brushes with |
177 | the brush patterns specified in Qt::BrushStyle. |
178 | \value PatternTransform The engine has support for transforming brush |
179 | patterns. |
180 | \value PerspectiveTransform The engine has support for performing perspective |
181 | transformations on primitives. |
182 | \value PixmapTransform The engine can transform pixmaps, including |
183 | rotation and shearing. |
184 | \value PorterDuff The engine supports Porter-Duff operations |
185 | \value PrimitiveTransform The engine has support for transforming |
186 | drawing primitives. |
187 | \value RadialGradientFill The engine supports radial gradient fills. |
188 | \value RasterOpModes The engine supports bitwise raster operations. |
189 | \value AllFeatures All of the above features. This enum value is usually |
190 | used as a bit mask. |
191 | */ |
192 | |
193 | /*! |
194 | \enum QPaintEngine::PolygonDrawMode |
195 | |
196 | \value OddEvenMode The polygon should be drawn using OddEven fill |
197 | rule. |
198 | |
199 | \value WindingMode The polygon should be drawn using Winding fill rule. |
200 | |
201 | \value ConvexMode The polygon is a convex polygon and can be drawn |
202 | using specialized algorithms where available. |
203 | |
204 | \value PolylineMode Only the outline of the polygon should be |
205 | drawn. |
206 | |
207 | */ |
208 | |
209 | /*! |
210 | \enum QPaintEngine::DirtyFlag |
211 | |
212 | \value DirtyPen The pen is dirty and needs to be updated. |
213 | |
214 | \value DirtyBrush The brush is dirty and needs to be updated. |
215 | |
216 | \value DirtyBrushOrigin The brush origin is dirty and needs to |
217 | updated. |
218 | |
219 | \value DirtyFont The font is dirty and needs to be updated. |
220 | |
221 | \value DirtyBackground The background is dirty and needs to be |
222 | updated. |
223 | |
224 | \value DirtyBackgroundMode The background mode is dirty and needs |
225 | to be updated. |
226 | |
227 | \value DirtyTransform The transform is dirty and needs to be |
228 | updated. |
229 | |
230 | \value DirtyClipRegion The clip region is dirty and needs to be |
231 | updated. |
232 | |
233 | \value DirtyClipPath The clip path is dirty and needs to be |
234 | updated. |
235 | |
236 | \value DirtyHints The render hints is dirty and needs to be |
237 | updated. |
238 | |
239 | \value DirtyCompositionMode The composition mode is dirty and |
240 | needs to be updated. |
241 | |
242 | \value DirtyClipEnabled Whether clipping is enabled or not is |
243 | dirty and needs to be updated. |
244 | |
245 | \value DirtyOpacity The constant opacity has changed and needs to |
246 | be updated as part of the state change in |
247 | QPaintEngine::updateState(). |
248 | |
249 | \value AllDirty Convenience enum used internally. |
250 | |
251 | These types are used by QPainter to trigger lazy updates of the |
252 | various states in the QPaintEngine using |
253 | QPaintEngine::updateState(). |
254 | |
255 | A paint engine must update every dirty state. |
256 | */ |
257 | |
258 | /*! |
259 | \fn void QPaintEngine::syncState() |
260 | |
261 | \internal |
262 | |
263 | Updates all dirty states in this engine. This function should ONLY |
264 | be used when drawing with native handles directly and immediate sync |
265 | from QPainters state to the native state is required. |
266 | */ |
267 | void QPaintEngine::syncState() |
268 | { |
269 | Q_ASSERT(state); |
270 | updateState(state: *state); |
271 | |
272 | if (isExtended()) |
273 | static_cast<QPaintEngineEx *>(this)->sync(); |
274 | } |
275 | |
276 | static QPaintEngine *qt_polygon_recursion = nullptr; |
277 | struct QT_Point { |
278 | int x; |
279 | int y; |
280 | }; |
281 | Q_DECLARE_TYPEINFO(QT_Point, Q_PRIMITIVE_TYPE); |
282 | |
283 | /*! |
284 | \fn void QPaintEngine::drawPolygon(const QPointF *points, int pointCount, |
285 | PolygonDrawMode mode) |
286 | |
287 | Reimplement this virtual function to draw the polygon defined |
288 | by the \a pointCount first points in \a points, using mode \a |
289 | mode. |
290 | |
291 | \note At least one of the drawPolygon() functions must be reimplemented. |
292 | */ |
293 | void QPaintEngine::drawPolygon(const QPointF *points, int pointCount, PolygonDrawMode mode) |
294 | { |
295 | Q_ASSERT_X(qt_polygon_recursion != this, "QPaintEngine::drawPolygon" , |
296 | "At least one drawPolygon function must be implemented" ); |
297 | qt_polygon_recursion = this; |
298 | Q_ASSERT(sizeof(QT_Point) == sizeof(QPoint)); |
299 | QVarLengthArray<QT_Point> p(pointCount); |
300 | for (int i = 0; i < pointCount; ++i) { |
301 | p[i].x = qRound(d: points[i].x()); |
302 | p[i].y = qRound(d: points[i].y()); |
303 | } |
304 | drawPolygon(points: (QPoint *)p.data(), pointCount, mode); |
305 | qt_polygon_recursion = nullptr; |
306 | } |
307 | |
308 | struct QT_PointF { |
309 | qreal x; |
310 | qreal y; |
311 | }; |
312 | Q_DECLARE_TYPEINFO(QT_PointF, Q_PRIMITIVE_TYPE); |
313 | |
314 | /*! |
315 | \overload |
316 | |
317 | Reimplement this virtual function to draw the polygon defined by the |
318 | \a pointCount first points in \a points, using mode \a mode. |
319 | |
320 | \note At least one of the drawPolygon() functions must be reimplemented. |
321 | */ |
322 | void QPaintEngine::drawPolygon(const QPoint *points, int pointCount, PolygonDrawMode mode) |
323 | { |
324 | Q_ASSERT_X(qt_polygon_recursion != this, "QPaintEngine::drawPolygon" , |
325 | "At least one drawPolygon function must be implemented" ); |
326 | qt_polygon_recursion = this; |
327 | Q_ASSERT(sizeof(QT_PointF) == sizeof(QPointF)); |
328 | QVarLengthArray<QT_PointF> p(pointCount); |
329 | for (int i=0; i<pointCount; ++i) { |
330 | p[i].x = points[i].x(); |
331 | p[i].y = points[i].y(); |
332 | } |
333 | drawPolygon(points: (QPointF *)p.data(), pointCount, mode); |
334 | qt_polygon_recursion = nullptr; |
335 | } |
336 | |
337 | /*! |
338 | \enum QPaintEngine::Type |
339 | |
340 | \value X11 |
341 | \value Windows |
342 | \value MacPrinter |
343 | \value CoreGraphics \macos's Quartz2D (CoreGraphics) |
344 | \value QuickDraw \macos's QuickDraw |
345 | \value QWindowSystem Qt for Embedded Linux |
346 | \value OpenGL |
347 | \value Picture QPicture format |
348 | \value SVG Scalable Vector Graphics XML format |
349 | \value Raster |
350 | \value Direct3D Windows only, Direct3D based engine |
351 | \value Pdf Portable Document Format |
352 | \value OpenVG |
353 | \value User First user type ID |
354 | \value MaxUser Last user type ID |
355 | \value OpenGL2 |
356 | \value PaintBuffer |
357 | \value Blitter |
358 | \value Direct2D Windows only, Direct2D based engine |
359 | */ |
360 | |
361 | /*! |
362 | \fn bool QPaintEngine::isActive() const |
363 | |
364 | Returns \c true if the paint engine is actively drawing; otherwise |
365 | returns \c false. |
366 | |
367 | \sa setActive() |
368 | */ |
369 | |
370 | /*! |
371 | \fn void QPaintEngine::setActive(bool state) |
372 | |
373 | Sets the active state of the paint engine to \a state. |
374 | |
375 | \sa isActive() |
376 | */ |
377 | |
378 | /*! |
379 | \fn bool QPaintEngine::begin(QPaintDevice *pdev) |
380 | |
381 | Reimplement this function to initialise your paint engine when |
382 | painting is to start on the paint device \a pdev. Return true if |
383 | the initialization was successful; otherwise return false. |
384 | |
385 | \sa end(), isActive() |
386 | */ |
387 | |
388 | /*! |
389 | \fn bool QPaintEngine::end() |
390 | |
391 | Reimplement this function to finish painting on the current paint |
392 | device. Return true if painting was finished successfully; |
393 | otherwise return false. |
394 | |
395 | \sa begin(), isActive() |
396 | */ |
397 | |
398 | |
399 | /*! |
400 | Draws the first \a pointCount points in the buffer \a points |
401 | */ |
402 | void QPaintEngine::drawPoints(const QPointF *points, int pointCount) |
403 | { |
404 | QPainter *p = painter(); |
405 | if (!p) |
406 | return; |
407 | |
408 | qreal penWidth = p->pen().widthF(); |
409 | if (penWidth == 0) |
410 | penWidth = 1; |
411 | |
412 | bool ellipses = p->pen().capStyle() == Qt::RoundCap; |
413 | |
414 | p->save(); |
415 | |
416 | QTransform transform; |
417 | if (p->pen().isCosmetic()) { |
418 | transform = p->transform(); |
419 | p->setTransform(transform: QTransform()); |
420 | } |
421 | |
422 | p->setBrush(p->pen().brush()); |
423 | p->setPen(Qt::NoPen); |
424 | |
425 | for (int i=0; i<pointCount; ++i) { |
426 | QPointF pos = transform.map(p: points[i]); |
427 | QRectF rect(pos.x() - penWidth / 2, pos.y() - penWidth / 2, penWidth, penWidth); |
428 | |
429 | if (ellipses) |
430 | p->drawEllipse(r: rect); |
431 | else |
432 | p->drawRect(rect); |
433 | } |
434 | |
435 | p->restore(); |
436 | } |
437 | |
438 | |
439 | /*! |
440 | Draws the first \a pointCount points in the buffer \a points |
441 | |
442 | The default implementation converts the first \a pointCount QPoints in \a points |
443 | to QPointFs and calls the floating point version of drawPoints. |
444 | |
445 | */ |
446 | void QPaintEngine::drawPoints(const QPoint *points, int pointCount) |
447 | { |
448 | Q_ASSERT(sizeof(QT_PointF) == sizeof(QPointF)); |
449 | QT_PointF fp[256]; |
450 | while (pointCount) { |
451 | int i = 0; |
452 | while (i < pointCount && i < 256) { |
453 | fp[i].x = points[i].x(); |
454 | fp[i].y = points[i].y(); |
455 | ++i; |
456 | } |
457 | drawPoints(points: (QPointF *)(void *)fp, pointCount: i); |
458 | points += i; |
459 | pointCount -= i; |
460 | } |
461 | } |
462 | |
463 | /*! |
464 | \fn void QPaintEngine::drawEllipse(const QRectF &rect) |
465 | |
466 | Reimplement this function to draw the largest ellipse that can be |
467 | contained within rectangle \a rect. |
468 | |
469 | The default implementation calls drawPolygon(). |
470 | */ |
471 | void QPaintEngine::drawEllipse(const QRectF &rect) |
472 | { |
473 | QPainterPath path; |
474 | path.addEllipse(rect); |
475 | if (hasFeature(feature: PainterPaths)) { |
476 | drawPath(path); |
477 | } else { |
478 | QPolygonF polygon = path.toFillPolygon(); |
479 | drawPolygon(points: polygon.data(), pointCount: polygon.size(), mode: ConvexMode); |
480 | } |
481 | } |
482 | |
483 | /*! |
484 | The default implementation of this function calls the floating |
485 | point version of this function |
486 | */ |
487 | void QPaintEngine::drawEllipse(const QRect &rect) |
488 | { |
489 | drawEllipse(rect: QRectF(rect)); |
490 | } |
491 | |
492 | /*! |
493 | \fn void QPaintEngine::drawPixmap(const QRectF &r, const QPixmap |
494 | &pm, const QRectF &sr) |
495 | |
496 | Reimplement this function to draw the part of the \a pm |
497 | specified by the \a sr rectangle in the given \a r. |
498 | */ |
499 | |
500 | |
501 | void qt_fill_tile(QPixmap *tile, const QPixmap &pixmap) |
502 | { |
503 | QPainter p(tile); |
504 | p.drawPixmap(x: 0, y: 0, pm: pixmap); |
505 | int x = pixmap.width(); |
506 | while (x < tile->width()) { |
507 | p.drawPixmap(x, y: 0, pm: *tile, sx: 0, sy: 0, sw: x, sh: pixmap.height()); |
508 | x *= 2; |
509 | } |
510 | int y = pixmap.height(); |
511 | while (y < tile->height()) { |
512 | p.drawPixmap(x: 0, y, pm: *tile, sx: 0, sy: 0, sw: tile->width(), sh: y); |
513 | y *= 2; |
514 | } |
515 | } |
516 | |
517 | Q_GUI_EXPORT void qt_draw_tile(QPaintEngine *gc, qreal x, qreal y, qreal w, qreal h, |
518 | const QPixmap &pixmap, qreal xOffset, qreal yOffset) |
519 | { |
520 | qreal yPos, xPos, drawH, drawW, yOff, xOff; |
521 | yPos = y; |
522 | yOff = yOffset; |
523 | while(yPos < y + h) { |
524 | drawH = pixmap.height() - yOff; // Cropping first row |
525 | if (yPos + drawH > y + h) // Cropping last row |
526 | drawH = y + h - yPos; |
527 | xPos = x; |
528 | xOff = xOffset; |
529 | while(xPos < x + w) { |
530 | drawW = pixmap.width() - xOff; // Cropping first column |
531 | if (xPos + drawW > x + w) // Cropping last column |
532 | drawW = x + w - xPos; |
533 | if (drawW > 0 && drawH > 0) |
534 | gc->drawPixmap(r: QRectF(xPos, yPos, drawW, drawH), pm: pixmap, sr: QRectF(xOff, yOff, drawW, drawH)); |
535 | xPos += drawW; |
536 | xOff = 0; |
537 | } |
538 | yPos += drawH; |
539 | yOff = 0; |
540 | } |
541 | } |
542 | |
543 | |
544 | /*! |
545 | Reimplement this function to draw the \a pixmap in the given \a |
546 | rect, starting at the given \a p. The pixmap will be |
547 | drawn repeatedly until the \a rect is filled. |
548 | */ |
549 | void QPaintEngine::drawTiledPixmap(const QRectF &rect, const QPixmap &pixmap, const QPointF &p) |
550 | { |
551 | int sw = pixmap.width(); |
552 | int sh = pixmap.height(); |
553 | |
554 | if (sw*sh < 8192 && sw*sh < 16*rect.width()*rect.height()) { |
555 | int tw = sw, th = sh; |
556 | while (tw*th < 32678 && tw < rect.width()/2) |
557 | tw *= 2; |
558 | while (tw*th < 32678 && th < rect.height()/2) |
559 | th *= 2; |
560 | QPixmap tile; |
561 | if (pixmap.depth() == 1) { |
562 | tile = QBitmap(tw, th); |
563 | } else { |
564 | tile = QPixmap(tw, th); |
565 | if (pixmap.hasAlphaChannel()) |
566 | tile.fill(fillColor: Qt::transparent); |
567 | } |
568 | qt_fill_tile(tile: &tile, pixmap); |
569 | qt_draw_tile(gc: this, x: rect.x(), y: rect.y(), w: rect.width(), h: rect.height(), pixmap: tile, xOffset: p.x(), yOffset: p.y()); |
570 | } else { |
571 | qt_draw_tile(gc: this, x: rect.x(), y: rect.y(), w: rect.width(), h: rect.height(), pixmap, xOffset: p.x(), yOffset: p.y()); |
572 | } |
573 | } |
574 | |
575 | /*! |
576 | \fn void QPaintEngine::drawImage(const QRectF &rectangle, const QImage |
577 | &image, const QRectF &sr, Qt::ImageConversionFlags flags) |
578 | |
579 | Reimplement this function to draw the part of the \a image |
580 | specified by the \a sr rectangle in the given \a rectangle using |
581 | the given conversion flags \a flags, to convert it to a pixmap. |
582 | */ |
583 | |
584 | void QPaintEngine::drawImage(const QRectF &r, const QImage &image, const QRectF &sr, |
585 | Qt::ImageConversionFlags flags) |
586 | { |
587 | QRectF baseSize(0, 0, image.width(), image.height()); |
588 | QImage im = image; |
589 | if (baseSize != sr) |
590 | im = im.copy(x: qFloor(v: sr.x()), y: qFloor(v: sr.y()), |
591 | w: qCeil(v: sr.width()), h: qCeil(v: sr.height())); |
592 | QPixmap pm = QPixmap::fromImage(image: im, flags); |
593 | drawPixmap(r, pm, sr: QRectF(QPointF(0, 0), pm.size())); |
594 | } |
595 | |
596 | /*! |
597 | \fn Type QPaintEngine::type() const |
598 | |
599 | Reimplement this function to return the paint engine \l{Type}. |
600 | */ |
601 | |
602 | /*! |
603 | \fn void QPaintEngine::fix_neg_rect(int *x, int *y, int *w, int *h); |
604 | |
605 | \internal |
606 | */ |
607 | |
608 | /*! |
609 | \fn bool QPaintEngine::testDirty(DirtyFlags df) |
610 | |
611 | \internal |
612 | */ |
613 | |
614 | /*! |
615 | \fn void QPaintEngine::clearDirty(DirtyFlags df) |
616 | |
617 | \internal |
618 | */ |
619 | |
620 | /*! |
621 | \fn void QPaintEngine::setDirty(DirtyFlags df) |
622 | |
623 | \internal |
624 | */ |
625 | |
626 | /*! |
627 | \fn bool QPaintEngine::hasFeature(PaintEngineFeatures feature) const |
628 | |
629 | Returns \c true if the paint engine supports the specified \a |
630 | feature; otherwise returns \c false. |
631 | */ |
632 | |
633 | /*! |
634 | \fn bool QPaintEngine::isExtended() const |
635 | |
636 | \internal |
637 | |
638 | Returns \c true if the paint engine is a QPaintEngineEx derivative. |
639 | */ |
640 | |
641 | /*! |
642 | \fn void QPaintEngine::updateState(const QPaintEngineState &state) |
643 | |
644 | Reimplement this function to update the state of a paint engine. |
645 | |
646 | When implemented, this function is responsible for checking the |
647 | paint engine's current \a state and update the properties that are |
648 | changed. Use the QPaintEngineState::state() function to find out |
649 | which properties that must be updated, then use the corresponding |
650 | \l {GetFunction}{get function} to retrieve the current values for |
651 | the given properties. |
652 | |
653 | \sa QPaintEngineState |
654 | */ |
655 | |
656 | /*! |
657 | Creates a paint engine with the featureset specified by \a caps. |
658 | */ |
659 | |
660 | QPaintEngine::QPaintEngine(PaintEngineFeatures caps) |
661 | : state(nullptr), |
662 | gccaps(caps), |
663 | active(0), |
664 | selfDestruct(false), |
665 | extended(false), |
666 | d_ptr(new QPaintEnginePrivate) |
667 | { |
668 | d_ptr->q_ptr = this; |
669 | } |
670 | |
671 | /*! |
672 | \internal |
673 | */ |
674 | |
675 | QPaintEngine::QPaintEngine(QPaintEnginePrivate &dptr, PaintEngineFeatures caps) |
676 | : state(nullptr), |
677 | gccaps(caps), |
678 | active(0), |
679 | selfDestruct(false), |
680 | extended(false), |
681 | d_ptr(&dptr) |
682 | { |
683 | d_ptr->q_ptr = this; |
684 | } |
685 | |
686 | /*! |
687 | Destroys the paint engine. |
688 | */ |
689 | QPaintEngine::~QPaintEngine() |
690 | { |
691 | } |
692 | |
693 | /*! |
694 | Returns the paint engine's painter. |
695 | */ |
696 | QPainter *QPaintEngine::painter() const |
697 | { |
698 | return state ? state->painter() : nullptr; |
699 | } |
700 | |
701 | /*! |
702 | The default implementation ignores the \a path and does nothing. |
703 | */ |
704 | |
705 | void QPaintEngine::drawPath(const QPainterPath &) |
706 | { |
707 | if (hasFeature(feature: PainterPaths)) { |
708 | qWarning(msg: "QPaintEngine::drawPath: Must be implemented when feature PainterPaths is set" ); |
709 | } |
710 | } |
711 | |
712 | /*! |
713 | This function draws the text item \a textItem at position \a p. The |
714 | default implementation of this function converts the text to a |
715 | QPainterPath and paints the resulting path. |
716 | */ |
717 | |
718 | void QPaintEngine::drawTextItem(const QPointF &p, const QTextItem &textItem) |
719 | { |
720 | const QTextItemInt &ti = static_cast<const QTextItemInt &>(textItem); |
721 | if (ti.glyphs.numGlyphs == 0) |
722 | return; |
723 | |
724 | if (ti.fontEngine->glyphFormat == QFontEngine::Format_ARGB) { |
725 | QVarLengthArray<QFixedPoint> positions; |
726 | QVarLengthArray<glyph_t> glyphs; |
727 | QTransform matrix = QTransform::fromTranslate(dx: p.x(), dy: p.y() - ti.fontEngine->ascent().toReal()); |
728 | ti.fontEngine->getGlyphPositions(glyphs: ti.glyphs, matrix, flags: ti.flags, glyphs_out&: glyphs, positions); |
729 | painter()->save(); |
730 | painter()->setRenderHint(hint: QPainter::SmoothPixmapTransform, |
731 | on: bool((painter()->renderHints() & QPainter::TextAntialiasing) |
732 | && !(painter()->font().styleStrategy() & QFont::NoAntialias))); |
733 | for (int i = 0; i < ti.glyphs.numGlyphs; ++i) { |
734 | QImage glyph = ti.fontEngine->bitmapForGlyph(glyphs[i], subPixelPosition: QFixedPoint(), t: QTransform()); |
735 | painter()->drawImage(x: positions[i].x.toReal(), y: positions[i].y.toReal(), image: glyph); |
736 | } |
737 | painter()->restore(); |
738 | return; |
739 | } |
740 | |
741 | QPainterPath path; |
742 | path.setFillRule(Qt::WindingFill); |
743 | ti.fontEngine->addOutlineToPath(0, 0, ti.glyphs, &path, flags: ti.flags); |
744 | if (!path.isEmpty()) { |
745 | painter()->save(); |
746 | painter()->setRenderHint(hint: QPainter::Antialiasing, |
747 | on: bool((painter()->renderHints() & QPainter::TextAntialiasing) |
748 | && !(painter()->font().styleStrategy() & QFont::NoAntialias))); |
749 | painter()->translate(dx: p.x(), dy: p.y()); |
750 | painter()->fillPath(path, brush: painter()->pen().brush()); |
751 | painter()->restore(); |
752 | } |
753 | } |
754 | |
755 | /*! |
756 | The default implementation splits the list of lines in \a lines |
757 | into \a lineCount separate calls to drawPath() or drawPolygon() |
758 | depending on the feature set of the paint engine. |
759 | */ |
760 | void QPaintEngine::drawLines(const QLineF *lines, int lineCount) |
761 | { |
762 | for (int i=0; i<lineCount; ++i) { |
763 | QPointF pts[2] = { lines[i].p1(), lines[i].p2() }; |
764 | |
765 | if (pts[0] == pts[1]) { |
766 | if (state->pen().capStyle() != Qt::FlatCap) |
767 | drawPoints(points: pts, pointCount: 1); |
768 | continue; |
769 | } |
770 | |
771 | drawPolygon(points: pts, pointCount: 2, mode: PolylineMode); |
772 | } |
773 | } |
774 | |
775 | /*! |
776 | \overload |
777 | |
778 | The default implementation converts the first \a lineCount lines |
779 | in \a lines to a QLineF and calls the floating point version of |
780 | this function. |
781 | */ |
782 | void QPaintEngine::drawLines(const QLine *lines, int lineCount) |
783 | { |
784 | struct PointF { |
785 | qreal x; |
786 | qreal y; |
787 | }; |
788 | struct LineF { |
789 | PointF p1; |
790 | PointF p2; |
791 | }; |
792 | Q_ASSERT(sizeof(PointF) == sizeof(QPointF)); |
793 | Q_ASSERT(sizeof(LineF) == sizeof(QLineF)); |
794 | LineF fl[256]; |
795 | while (lineCount) { |
796 | int i = 0; |
797 | while (i < lineCount && i < 256) { |
798 | fl[i].p1.x = lines[i].x1(); |
799 | fl[i].p1.y = lines[i].y1(); |
800 | fl[i].p2.x = lines[i].x2(); |
801 | fl[i].p2.y = lines[i].y2(); |
802 | ++i; |
803 | } |
804 | drawLines(lines: (QLineF *)(void *)fl, lineCount: i); |
805 | lines += i; |
806 | lineCount -= i; |
807 | } |
808 | } |
809 | |
810 | |
811 | /*! |
812 | \overload |
813 | |
814 | The default implementation converts the first \a rectCount |
815 | rectangles in the buffer \a rects to a QRectF and calls the |
816 | floating point version of this function. |
817 | */ |
818 | void QPaintEngine::drawRects(const QRect *rects, int rectCount) |
819 | { |
820 | struct RectF { |
821 | qreal x; |
822 | qreal y; |
823 | qreal w; |
824 | qreal h; |
825 | }; |
826 | Q_ASSERT(sizeof(RectF) == sizeof(QRectF)); |
827 | RectF fr[256]; |
828 | while (rectCount) { |
829 | int i = 0; |
830 | while (i < rectCount && i < 256) { |
831 | fr[i].x = rects[i].x(); |
832 | fr[i].y = rects[i].y(); |
833 | fr[i].w = rects[i].width(); |
834 | fr[i].h = rects[i].height(); |
835 | ++i; |
836 | } |
837 | drawRects(rects: (QRectF *)(void *)fr, rectCount: i); |
838 | rects += i; |
839 | rectCount -= i; |
840 | } |
841 | } |
842 | |
843 | /*! |
844 | Draws the first \a rectCount rectangles in the buffer \a |
845 | rects. The default implementation of this function calls drawPath() |
846 | or drawPolygon() depending on the feature set of the paint engine. |
847 | */ |
848 | void QPaintEngine::drawRects(const QRectF *rects, int rectCount) |
849 | { |
850 | if (hasFeature(feature: PainterPaths) && |
851 | !state->penNeedsResolving() && |
852 | !state->brushNeedsResolving()) { |
853 | for (int i=0; i<rectCount; ++i) { |
854 | QPainterPath path; |
855 | path.addRect(rect: rects[i]); |
856 | if (path.isEmpty()) |
857 | continue; |
858 | drawPath(path); |
859 | } |
860 | } else { |
861 | for (int i=0; i<rectCount; ++i) { |
862 | QRectF rf = rects[i]; |
863 | QPointF pts[4] = { QPointF(rf.x(), rf.y()), |
864 | QPointF(rf.x() + rf.width(), rf.y()), |
865 | QPointF(rf.x() + rf.width(), rf.y() + rf.height()), |
866 | QPointF(rf.x(), rf.y() + rf.height()) }; |
867 | drawPolygon(points: pts, pointCount: 4, mode: ConvexMode); |
868 | } |
869 | } |
870 | } |
871 | |
872 | /*! |
873 | \internal |
874 | Sets the paintdevice that this engine operates on to \a device |
875 | */ |
876 | void QPaintEngine::setPaintDevice(QPaintDevice *device) |
877 | { |
878 | d_func()->pdev = device; |
879 | } |
880 | |
881 | /*! |
882 | Returns the device that this engine is painting on, if painting is |
883 | active; otherwise returns \nullptr. |
884 | */ |
885 | QPaintDevice *QPaintEngine::paintDevice() const |
886 | { |
887 | return d_func()->pdev; |
888 | } |
889 | |
890 | |
891 | /*! |
892 | \internal |
893 | |
894 | Returns the offset from the painters origo to the engines |
895 | origo. This value is used by QPainter for engines who have |
896 | internal double buffering. |
897 | |
898 | This function only makes sense when the engine is active. |
899 | */ |
900 | QPoint QPaintEngine::coordinateOffset() const |
901 | { |
902 | return QPoint(); |
903 | } |
904 | |
905 | /*! |
906 | \internal |
907 | |
908 | Sets the system clip for this engine. The system clip defines the |
909 | basis area that the engine has to draw in. All clips that are |
910 | set will be an intersection with the system clip. |
911 | |
912 | Reset the systemclip to no clip by setting an empty region. |
913 | */ |
914 | void QPaintEngine::setSystemClip(const QRegion ®ion) |
915 | { |
916 | Q_D(QPaintEngine); |
917 | d->baseSystemClip = region; |
918 | // Be backward compatible and only call d->systemStateChanged() |
919 | // if we currently have a system transform/viewport set. |
920 | d->updateSystemClip(); |
921 | if (d->hasSystemTransform || d->hasSystemViewport) { |
922 | d->systemStateChanged(); |
923 | } |
924 | } |
925 | |
926 | /*! |
927 | \internal |
928 | |
929 | Returns the system clip. The system clip is read only while the |
930 | painter is active. An empty region indicates that system clip |
931 | is not in use. |
932 | */ |
933 | |
934 | QRegion QPaintEngine::systemClip() const |
935 | { |
936 | return d_func()->systemClip; |
937 | } |
938 | |
939 | /*! |
940 | \internal |
941 | |
942 | Sets the target rect for drawing within the backing store. This |
943 | function should ONLY be used by the backing store. |
944 | */ |
945 | void QPaintEngine::setSystemRect(const QRect &rect) |
946 | { |
947 | if (isActive()) { |
948 | qWarning(msg: "QPaintEngine::setSystemRect: Should not be changed while engine is active" ); |
949 | return; |
950 | } |
951 | d_func()->systemRect = rect; |
952 | } |
953 | |
954 | /*! |
955 | \internal |
956 | |
957 | Retrieves the rect for drawing within the backing store. This |
958 | function should ONLY be used by the backing store. |
959 | */ |
960 | QRect QPaintEngine::systemRect() const |
961 | { |
962 | return d_func()->systemRect; |
963 | } |
964 | |
965 | /*! |
966 | \internal |
967 | |
968 | Creates a QPixmap optimized for this paint engine and device. |
969 | */ |
970 | QPixmap QPaintEngine::createPixmap(QSize size) |
971 | { |
972 | if (Q_UNLIKELY(!qobject_cast<QGuiApplication *>(QCoreApplication::instance()))) { |
973 | qWarning(msg: "QPaintEngine::createPixmap: QPixmap cannot be created without a QGuiApplication" ); |
974 | return QPixmap(); |
975 | } |
976 | |
977 | std::unique_ptr<QPlatformPixmap> data(QGuiApplicationPrivate::platformIntegration()->createPlatformPixmap(type: QPlatformPixmap::PixmapType)); |
978 | data->resize(width: size.width(), height: size.height()); |
979 | return QPixmap(data.release()); |
980 | } |
981 | |
982 | /*! |
983 | \internal |
984 | |
985 | Creates a QPixmap optimized for this paint engine and device. |
986 | */ |
987 | QPixmap QPaintEngine::createPixmapFromImage(QImage image, Qt::ImageConversionFlags flags) |
988 | { |
989 | if (Q_UNLIKELY(!qobject_cast<QGuiApplication *>(QCoreApplication::instance()))) { |
990 | qWarning(msg: "QPaintEngine::createPixmapFromImage: QPixmap cannot be created without a QGuiApplication" ); |
991 | return QPixmap(); |
992 | } |
993 | |
994 | std::unique_ptr<QPlatformPixmap> data(QGuiApplicationPrivate::platformIntegration()->createPlatformPixmap(type: QPlatformPixmap::PixmapType)); |
995 | if (image.isDetached()) |
996 | data->fromImageInPlace(image, flags); |
997 | else |
998 | data->fromImage(image, flags); |
999 | return QPixmap(data.release()); |
1000 | } |
1001 | |
1002 | QPaintEnginePrivate::~QPaintEnginePrivate() |
1003 | { |
1004 | } |
1005 | |
1006 | void QPaintEnginePrivate::drawBoxTextItem(const QPointF &p, const QTextItemInt &ti) |
1007 | { |
1008 | if (!ti.glyphs.numGlyphs) |
1009 | return; |
1010 | |
1011 | // any fixes here should probably also be done in QFontEngineBox::draw |
1012 | const int size = qRound(f: ti.fontEngine->ascent()); |
1013 | QVarLengthArray<QFixedPoint> positions; |
1014 | QVarLengthArray<glyph_t> glyphs; |
1015 | QTransform matrix = QTransform::fromTranslate(dx: p.x(), dy: p.y() - size); |
1016 | ti.fontEngine->getGlyphPositions(glyphs: ti.glyphs, matrix, flags: ti.flags, glyphs_out&: glyphs, positions); |
1017 | if (glyphs.size() == 0) |
1018 | return; |
1019 | |
1020 | QSize s(size - 3, size - 3); |
1021 | |
1022 | QPainter *painter = q_func()->state->painter(); |
1023 | painter->save(); |
1024 | painter->setBrush(Qt::NoBrush); |
1025 | QPen pen = painter->pen(); |
1026 | pen.setWidthF(ti.fontEngine->lineThickness().toReal()); |
1027 | painter->setPen(pen); |
1028 | for (int k = 0; k < positions.size(); k++) |
1029 | painter->drawRect(rect: QRectF(positions[k].toPointF(), s)); |
1030 | painter->restore(); |
1031 | } |
1032 | |
1033 | QT_END_NAMESPACE |
1034 | |