QPaintEngine Class Reference
Detailed Description
The QPaintEngine class provides an abstract definition of how QPainter draws to a given device on a given platform.Qt 4.0 provides several premade implementations of QPaintEngine for the different painter backends we support. We provide one paint engine for each window system and painting framework we support. This includes X11 on Unix/Linux and CoreGraphics on Mac OS X. In addition we provide QPaintEngine implementations for OpenGL (accessible through QGLWidget) and PostScript (accessible through QPSPrinter on X11). Additionally there is a raster-based paint engine that is a fallback for when an engine does not support a certain capability.
If one wants to use QPainter to draw to a different backend, one must subclass QPaintEngine and reimplement all its virtual functions. The QPaintEngine implementation is then made available by subclassing QPaintDevice and reimplementing the virtual function QPaintDevice::paintEngine().
QPaintEngine is created and owned by the QPaintDevice that created it.
The big advantage of the QPaintEngine approach opposed to Qt 3's QPainter/QPaintDevicecmd() approach is that it is now possible to adapt to multiple technologies on each platform and take advantage of each to the fullest.
- See also:
- QPainter, QPaintDevice::paintEngine(), {The Paint System}
Definition at line 85 of file qpaintengine.h.
Public Types | |
| enum | DirtyFlag { DirtyPen = 0x0001, DirtyBrush = 0x0002, DirtyBrushOrigin = 0x0004, DirtyFont = 0x0008, DirtyBackground = 0x0010, DirtyBackgroundMode = 0x0020, DirtyTransform = 0x0040, DirtyClipRegion = 0x0080, DirtyClipPath = 0x0100, DirtyHints = 0x0200, DirtyCompositionMode = 0x0400, DirtyClipEnabled = 0x0800, DirtyOpacity = 0x1000, AllDirty = 0xffff } |
| enum | PaintEngineFeature { PrimitiveTransform = 0x00000001, PatternTransform = 0x00000002, PixmapTransform = 0x00000004, PatternBrush = 0x00000008, LinearGradientFill = 0x00000010, RadialGradientFill = 0x00000020, ConicalGradientFill = 0x00000040, AlphaBlend = 0x00000080, PorterDuff = 0x00000100, PainterPaths = 0x00000200, Antialiasing = 0x00000400, BrushStroke = 0x00000800, ConstantOpacity = 0x00001000, MaskedBrush = 0x00002000, PerspectiveTransform = 0x00004000, BlendModes = 0x00008000, ObjectBoundingModeGradients = 0x00010000, PaintOutsidePaintEvent = 0x20000000, AllFeatures = 0xffffffff } |
| enum | PolygonDrawMode { OddEvenMode, WindingMode, ConvexMode, PolylineMode } |
| enum | Type { X11, Windows, QuickDraw, CoreGraphics, MacPrinter, QWindowSystem, PostScript, OpenGL, Picture, SVG, Raster, Direct3D, Pdf, User = 50, MaxUser = 100 } |
Public Member Functions | |
| virtual bool | begin (QPaintDevice *pdev)=0 |
| void | clearDirty (DirtyFlags df) |
| virtual QPoint | coordinateOffset () const |
| virtual void | drawEllipse (const QRect &r) |
| virtual void | drawEllipse (const QRectF &r) |
| virtual void | drawImage (const QRectF &r, const QImage &pm, const QRectF &sr, Qt::ImageConversionFlags flags=Qt::AutoColor) |
| virtual void | drawLines (const QLineF *lines, int lineCount) |
| virtual void | drawLines (const QLine *lines, int lineCount) |
| virtual void | drawPath (const QPainterPath &path) |
| virtual void | drawPixmap (const QRectF &r, const QPixmap &pm, const QRectF &sr)=0 |
| virtual void | drawPoints (const QPoint *points, int pointCount) |
| virtual void | drawPoints (const QPointF *points, int pointCount) |
| virtual void | drawPolygon (const QPoint *points, int pointCount, PolygonDrawMode mode) |
| virtual void | drawPolygon (const QPointF *points, int pointCount, PolygonDrawMode mode) |
| virtual void | drawRects (const QRectF *rects, int rectCount) |
| virtual void | drawRects (const QRect *rects, int rectCount) |
| virtual void | drawTextItem (const QPointF &p, const QTextItem &textItem) |
| virtual void | drawTiledPixmap (const QRectF &r, const QPixmap &pixmap, const QPointF &s) |
| virtual bool | end ()=0 |
| void | fix_neg_rect (int *x, int *y, int *w, int *h) |
| bool | hasFeature (PaintEngineFeatures feature) const |
| bool | isActive () const |
| QPaintDevice * | paintDevice () const |
| QPainter * | painter () const |
| QPaintEngine (PaintEngineFeatures features=0) | |
| void | setActive (bool newState) |
| void | setDirty (DirtyFlags df) |
| void | setPaintDevice (QPaintDevice *device) |
| void | setSystemClip (const QRegion &baseClip) |
| void | setSystemRect (const QRect &rect) |
| void | syncState () |
| QRegion | systemClip () const |
| QRect | systemRect () const |
| bool | testDirty (DirtyFlags df) |
| virtual Type | type () const =0 |
| virtual void | updateState (const QPaintEngineState &state)=0 |
| virtual | ~QPaintEngine () |
Protected Member Functions | |
| QPaintEngine (QPaintEnginePrivate &data, PaintEngineFeatures devcaps=0) | |
Protected Attributes | |
| uint | active: 1 |
| QPaintEnginePrivate * | d_ptr |
| PaintEngineFeatures | gccaps |
| uint | selfDestruct: 1 |
| QPaintEngineState * | state |
Private Member Functions | |
| bool | autoDestruct () const |
| void | setAutoDestruct (bool autoDestr) |
Friends | |
| class | QFontEngineBox |
| class | QFontEngineFT |
| class | QFontEngineMac |
| class | QFontEngineQPF |
| class | QFontEngineQPF1 |
| class | QFontEngineWin |
| class | QMacCGContext |
| class | QMacPrintEngine |
| class | QMacPrintEnginePrivate |
| class | QPainter |
| class | QPainterPrivate |
| class | QPreviewPaintEngine |
| class | QPSPrintEngine |
| class | QWidget |
| class | QWidgetPrivate |
| class | QWin32PaintEngine |
| class | QWin32PaintEnginePrivate |
The documentation for this class was generated from the following files:
- qt-x11-opensource-src-4.4.3/src/gui/painting/qpaintengine.h
- qt-x11-opensource-src-4.4.3/src/gui/painting/qpaintengine.cpp