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Diffstat (limited to 'src/gui/doc/src/paintsystem.qdoc')
| -rw-r--r-- | src/gui/doc/src/paintsystem.qdoc | 182 |
1 files changed, 7 insertions, 175 deletions
diff --git a/src/gui/doc/src/paintsystem.qdoc b/src/gui/doc/src/paintsystem.qdoc index 0864c3ba4a..ea0a3bdad6 100644 --- a/src/gui/doc/src/paintsystem.qdoc +++ b/src/gui/doc/src/paintsystem.qdoc @@ -78,8 +78,6 @@ \li \l{Drawing and Filling} \li \l{Coordinate System} \li \l{Reading and Writing Image Files} - \li \l{Styling} - \li \l{Printing with Qt} \endlist \section1 Classes for Painting @@ -88,11 +86,6 @@ \annotatedlist painting - Alternatively, Qt provides the QtOpenGL module, offering classes - that makes it easy to use OpenGL in Qt applications. Among others, - the module provides an OpenGL widget class that can be used just - like any other Qt widget, except that it opens an OpenGL display - buffer where the OpenGL API can be used to render the contents. */ @@ -108,18 +101,12 @@ The QPaintDevice class is the base class of objects that can be painted, i.e. QPainter can draw on any QPaintDevice subclass. QPaintDevice's drawing capabilities are currently - implemented by the QWidget, QImage, QPixmap, QGLWidget, - QGLPixelBuffer, QPicture and QPrinter subclasses. + implemented by the QImage, QPixmap, QGLPixelBuffer, QPicture and + QPrinter subclasses. \image paintsystem-devices.png \table 100% - \row \li \b Widget - - The QWidget class is the base class of all user interface - objects. The widget is the atom of the user interface: it receives - mouse, keyboard and other events from the window system, and - paints a representation of itself on the screen. \row \li \b Image @@ -152,40 +139,13 @@ Qt also provides the QBitmap convenience class, inheriting QPixmap. QBitmap guarantees monochrome (1-bit depth) pixmaps, and is mainly used for creating custom QCursor and QBrush objects, - constructing QRegion objects, and for setting masks for pixmaps - and widgets. - - \row \li \b {OpenGL Widget} - - As mentioned previously, Qt provides the QtOpenGL module offering - classes that makes it easy to use OpenGL in Qt applications. For - example, the QGLWidget enables the OpenGL API for - rendering. - - But QGLWidget is also a QWidget subclass, and can be used by - QPainter as any other paint device. One huge benefit from this is - that it enables Qt to utilize the high performance of OpenGL for - most drawing operations, such as transformations and pixmap - drawing. - - \row \li \b {Pixel Buffer} + constructing QRegion objects. - The QtOpenGL module also provides the QGLPixelBuffer class which - inherits QPaintDevice directly. + \row \li \b {OpenGL Paint Device} - QGLPixelBuffer encapsulates an OpenGL pbuffer. Rendering into a - pbuffer is normally done using full hardware acceleration which - can be significantly faster than rendering into a QPixmap. - - \row \li \b {Framebuffer Object} - - The QtOpenGL module also provides the QGLFramebufferObject class - which inherits QPaintDevice directly. - - QGLFramebufferObject encapsulates an OpenGL framebuffer object. - Framebuffer objects can also be used for off-screen rendering, and - offer several advantages over pixel buffers for this purpose. - These are described in the QGLFramebufferObject class documentation. + As mentioned previously, Qt is offering classes that makes it easy + to use OpenGL in Qt applications. For example, the QOpenGLPaintDevice + enables the OpenGL API for rendering with QPainter. \row \li \b {Picture} @@ -199,23 +159,7 @@ Qt provides the QPicture::load() and QPicture::save() functions as well as streaming operators for loading and saving pictures. - \row \li \b {Printer} - - The QPrinter class is a paint device that paints on a printer. On - Windows or Mac OS X, QPrinter uses the built-in printer - drivers. On X11, QPrinter generates postscript and sends that to - lpr, lp, or another print program. QPrinter can also print to any - other QPrintEngine object. - - The QPrintEngine class defines an interface for how QPrinter - interacts with a given printing subsystem. The common case when - creating your own print engine, is to derive from both - QPaintEngine and QPrintEngine. - The output format is by default determined by the platform the - printer is running on, but by explicitly setting the output format - to QPrinter::PdfFormat, QPrinter will generate its output as a PDF - file. \row \li \b {Custom Backends} @@ -229,43 +173,6 @@ \endtable - \section1 Selecting the Painting Backend - - Since Qt 4.5, it is possible to replace the paint engines and paint - devices used for widgets, pixmaps and the offscreen double buffer. By - default the backends are: - - \table - \row - \li Windows - \li Software Rasterizer - \row - \li X11 - \li X11 - \row - \li Mac OS X - \li CoreGraphics - \row - \li Embedded - \li Software Rasterizer - \endtable - - Passing a command line parameter to the application, such as, - \c{-graphicssystem raster}, specifies that Qt should use the software - rasterizer for this application. The Software rasterizer is fully - supported on all platforms. - - \code - > analogclock -graphicssystem raster - \endcode - - There is also a \c{-graphicssystem opengl} mode that uses OpenGL for - all drawing. Currently, this engine is experimental as it does not draw - everything correctly. - - Qt also supports being configured using \c {-graphicssystem - raster|opengl} in which case all applications will use the - specified graphics system for its graphics. */ /*! @@ -360,12 +267,6 @@ colors are mapped to hardware using the QColormap class). For more information, see the QColor class documentation. - When creating a new widget, it is recommend to use the colors in - the widget's palette rather than hard-coding specific colors. All - widgets in Qt contain a palette and use their palette to draw - themselves. A widget's palette is represented by the QPalette - class which contains color groups for each widget state. - The available fill patterns are described by the Qt::BrushStyle enum. These include basic patterns spanning from uniform color to very sparse pattern, various line combinations, gradient fills and @@ -398,7 +299,6 @@ \previouspage Coordinate System \contentspage The Paint System - \nextpage Styling The most common way to read images is through QImage and QPixmap's constructors, or by calling the QImage::load() and QPixmap::load() @@ -446,71 +346,3 @@ and start using it. */ -/*! - \page paintsystem-styling.html - \title Styling - - \previouspage Reading and Writing Image Files - \contentspage The Paint System - \nextpage Printing with Qt - - Qt's built-in widgets use the QStyle class to perform nearly all - of their drawing. QStyle is an abstract base class that - encapsulates the look and feel of a GUI, and can be used to make - the widgets look exactly like the equivalent native widgets or to - give the widgets a custom look. - - Qt provides a set of QStyle subclasses that emulate the native - look of the different platforms supported by Qt (QWindowsStyle, - QMacStyle, QMotifStyle, etc.). These styles are built into the - QtGui library, other styles can be made available using Qt's - plugin mechansim. - - Most functions for drawing style elements take four arguments: - - \list - \li an enum value specifying which graphical element to draw - \li a QStyleOption object specifying how and where to render that element - \li a QPainter object that should be used to draw the element - \li a QWidget object on which the drawing is performed (optional) - \endlist - - The style gets all the information it needs to render the - graphical element from the QStyleOption class. The widget is - passed as the last argument in case the style needs it to perform - special effects (such as animated default buttons on Mac OS X), - but it isn't mandatory. In fact, QStyle can be used to draw on any - paint device (not just widgets), in which case the widget argument - is a zero pointer. - - \image paintsystem-stylepainter.png - - The paint system also provides the QStylePainter class inheriting - from QPainter. QStylePainter is a convenience class for drawing - QStyle elements inside a widget, and extends QPainter with a set - of high-level drawing functions implemented on top of QStyle's - API. The advantage of using QStylePainter is that the parameter - lists get considerably shorter. - - \table 100% - \row - \li \inlineimage paintsystem-icon.png - \li \b QIcon - - The QIcon class provides scalable icons in different modes and states. - - QIcon can generate pixmaps reflecting an icon's state, mode and - size. These pixmaps are generated from the set of pixmaps - made available to the icon, and are used by Qt widgets to show an - icon representing a particular action. - - The rendering of a QIcon object is handled by the QIconEngine - class. Each icon has a corresponding icon engine that is - responsible for drawing the icon with a requested size, mode and - state. - - \endtable - - For more information about widget styling and appearance, see the - \l{Styles and Style Aware Widgets}. -*/ |