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| author | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-07-10 15:24:15 -0500 |
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| committer | Timothy Pearson <kb9vqf@pearsoncomputing.net> | 2011-07-10 15:24:15 -0500 |
| commit | bd0f3345a938b35ce6a12f6150373b0955b8dd12 (patch) | |
| tree | 7a520322212d48ebcb9fbe1087e7fca28b76185c /doc/html/emb-classes.html | |
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diff --git a/doc/html/emb-classes.html b/doc/html/emb-classes.html new file mode 100644 index 0000000..c3f6452 --- /dev/null +++ b/doc/html/emb-classes.html @@ -0,0 +1,339 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/doc/embclasses.doc:36 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>The Qt/Embedded-specific classes</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>The Qt/Embedded-specific classes</h1> + + + +<p> Qt/Embedded classes fall into two groups: the majority are used by +every Qt/Embedded program, and some are used only by the Qt/Embedded server. +The Qt/Embedded server program can also be a client, as in the case of a +single-process installation. All Qt/Embedded specific source files live +in <tt>src/kernel</tt> and are suffixed <tt>_qws</tt>. The » symbol +indicates inheritance. +<p> <!-- toc --> +<ul> +<li><a href="#1"> QFontManager +</a> +<li><a href="#2"> QDiskFont +</a> +<li><a href="#3"> QRenderedFont +</a> +<li><a href="#4"> QFontFactory (and descendants QFontFactoryBDF, QFontFactoryTtf) +</a> +<li><a href="#5"> QGlyph +</a> +<li><a href="#6"> QMemoryManagerPixmap/QMemoryManager +</a> +<li><a href="#7"> QScreen » QLinuxFbScreen » accelerated screens, QTransformedScreen » QVfbScreen +</a> +<li><a href="#8"> QScreenCursor » accelerated cursor » QVfbCursor +</a> +<li><a href="#9"> QGfx » RasterBase » Raster » accelerated driver » QGfxVfb » QGfxTransformedRaster +</a> +<li><a href="#10"> QLock, QLockHolder +</a> +<li><a href="#11"> QDirectPainter +</a> +<li><a href="#12"> QWSSoundServer, Client +</a> +<li><a href="#13"> QWSWindow +</a> +<li><a href="#14"> QWSKeyboardHandler » subtypes +</a> +<li><a href="#15"> QWSMouseHandler » QWSCalibratedMouseHandler » mouse types +</a> +<li><a href="#16"> QWSDisplay +</a> +<li><a href="#17"> QWSServer +</a> +<li><a href="#18"> QWSClient +</a> +<li><a href="#19"> QWSDisplayData +</a> +<li><a href="#20"> QWSCommands +</a> +<li><a href="#21"> QCopChannel +</a> +<li><a href="#22"> QWSManager +</a> +<li><a href="#23"> QWSDecoration +</a> +<li><a href="#24"> QWSPropertyManager +</a> +<li><a href="#25"> QWSRegionManager +</a> +<li><a href="#26"> QWSSocket, QWSServerSocket +</a> +</ul> +<!-- endtoc --> + +<p> <h2> <a href="qfontmanager.html">QFontManager</a> +</h2> +<a name="1"></a><p> There is one of these per application. At application startup time it +reads the font definition file from <tt>$QTDIR/etc/fonts/fontdir</tt> (or <tt>/usr/local/etc/qt-embedded/fonts/fontdir</tt> if QTDIR is undefined). It +keeps track of all font information and maintains a cache of rendered +fonts. It also creates the font factories: QFontManager::QFontManager +is the place to add constructors for new factories. It provides a +high-level interface for requesting a particular font and calls +QFontFactories to load fonts from disk on demand. Note that this only +applies to BDF and TrueType fonts; Qt/Embedded's optimised <tt>.qpf</tt> +font file format bypasses the QFontManager mechanism altogether. +<p> There should be no need to modify this class unless you wish to change +font matching or caching behaviour. +<p> <h2> QDiskFont +</h2> +<a name="2"></a><p> This contains information about a single on-disk font file (e.g. +<tt>/usr/local/etc/qt-embedded/times.ttf</tt>). It holds the file path, +information about whether the font is scalable, its weight, size, +Qt/Embedded name, etc. This information is used so that <a href="qfontmanager.html">QFontManager</a> +can find the closest matching disk font (it uses a scoring mechanism +weighted towards matching names, then whether the font's italic, then +its weight). +<p> There should be no reason to modify this class. +<p> <h2> QRenderedFont +</h2> +<a name="3"></a><p> There is one and only one QRenderedFont for every unique font +currently loaded by the system (that is, each unique combination of +name, size, weight, italic or not, anti-aliased or not). +QRenderedFonts are reference counted; once no one is using the +QRenderedFont it is deleted along with its cache of glyph bitmaps. The +QDiskFont it was loaded from remains opened by its QFontFactory. +<p> There should be no reason to modify this class, unless you wish to +change the way in which glyphs are cached. +<p> <h2> QFontFactory (and descendants QFontFactoryBDF, QFontFactoryTtf) +</h2> +<a name="4"></a><p> These provide support for particular font formats, for instance the +scalable Truetype and Type1 formats (both supported in +QFontFactoryTtf, which uses Freetype 2) and the bitmap BDF format used +by X. It's called to open an on-disk font; once a font is opened it +remains opened so that the creation of new font instances from the +disk font is fast. It can also create a QRenderedFont and convert from +Unicode values to an index into the font file. For compactness, glyphs +are stored in the order and indexes they are defined in the font +rather than in Unicode order. +<p> There should be no need to modify this class, but it should be +inherited if you wish to add a different type of font renderer (e.g. +for a custom vector font format). +<p> <h2> QGlyph +</h2> +<a name="5"></a><p> This describes a particular image of a character from a QRenderedFont: +for example, the letter 'A' at 10 points in Times New Roman, bold italic, +anti-aliased. It contains pointers to a QGlyphMetrics structure with +information about the character and to the raw data for the glyph: +this is either a 1-bit mask or an 8-bit alpha channel. Each QRenderedFont +creates these on demand and caches them once created (note that this is +not currently implemented for TrueType fonts). +<p> You would only need to modify this class if you were, for example, +modifying Qt/Embedded to support textured fonts, in which case you +would also need to modify QGfxRaster. +<p> <h2> QMemoryManagerPixmap/QMemoryManager +</h2> +<a name="6"></a><p> This handles requests for space for pixmaps and also keeps track of +QPF format fonts (these are small 'state dumps' of QRenderedFonts, +typically 2-20KB in size; they can be mmap'd direct from disk in order +to save memory). If a QPF font is found which matches a font request +no new QRenderedFont need be created for it. It's possible to strip out +all QFontFactory support and simply use QPFs if your font needs are modest +(for instance, if you only require a few fixed point sizes). Note that +no best-match loading is performed with QPFs, as opposed to those +loaded via <a href="qfontmanager.html">QFontManager</a>, so if you don't have the correct QPF for a point +size, text in that size will simply not be displayed. +<p> There should be no need to modify this class. +<p> <h2> <a href="qscreen.html">QScreen</a> » QLinuxFbScreen » accelerated screens, QTransformedScreen » QVfbScreen +</h2> +<a name="7"></a><p> These encapsulate the framebuffer Qt/Embedded is drawing to, provide +support for mapping of coordinates for rotating framebuffers, allow +manipulation of the colour palette and provide access to offscreen +graphics memory for devices with separate framebuffer memories. +<p> This is used for caching pixmaps and allowing accelerated pixmap=>screen +blt's. QLinuxFbScreen and the accelerated screens use the Linux <tt>/dev/fb</tt> +interface to get access to graphics memory and information about the +characteristics of the device. The framebuffer device to open is specified +by QWS_DISPLAY. Only QTransformedScreen implements the support for rotated +framebuffers. QVfbScreen provides an X window containing an emulated +framebuffer (a chunk of shared memory is set aside as the 'framebuffer' +and blt'd into the X window): this is intended as a debugging device +allowing users to debug their applications under Qt/Embedded without leaving +X. The accelerated screen drivers check to see if they can drive the +device specified by QWS_CARD_SLOT (which defaults to the usual position +of an AGP slot if not specified) and mmap its on-chip registers from +<tt>/dev/mem</tt>. They may also do chip-specific setup (initialising registers to +known values and so on). Finally, <a href="qscreen.html">QScreen</a>'s are used to create new +QScreenCursors and QGfxes. +<p> If you wish to modify the way pixmaps are allocated in memory, +subclass or modify QLinuxFbScreen. If you're writing an accelerated +driver you will need to subclass QScreen or QLinuxFbScreen. +<p> <h2> QScreenCursor » accelerated cursor » QVfbCursor +</h2> +<a name="8"></a><p> This handles drawing the on-screen mouse cursor, and saving and +restoring the screen under it for the non-accelerated cursor types. +<p> Subclassing QScreenCursor is optional in an accelerated driver (you +would only want to do so if the hardware supports a hardware cursor). +<p> <h2> QGfx » RasterBase » Raster » accelerated driver » QGfxVfb » QGfxTransformedRaster +</h2> +<a name="9"></a><p> This class encapsulates drawing operations, a little like a low-level +<a href="qpainter.html">QPainter</a>. QGfxRaster and its descendants are specifically intended +for drawing into a raw framebuffer. They can take an offset for drawing +operations and a clipping region in order to support drawing into windows. +You will need to subclass the QGfxRaster template in order to implement +an accelerated driver. +<p> If you're brave, modifying QGfxRaster would allow you to customise how +drawing is done or add support for a new bit depth/pixel format. +<p> <h2> QLock, QLockHolder +</h2> +<a name="10"></a><p> This encapsulates a System V semaphore, used for synchronising access +to memory shared between Qt/Embedded clients. QLockHolder is a utility class +to make managing and destroying QLocks easier. +<p> There should be no need to modify this class unless porting +Qt/Embedded to an operating system without System V IPC. +<p> <h2> <a href="qdirectpainter.html">QDirectPainter</a> +</h2> +<a name="11"></a><p> This is a QPainter which also gives you a pointer to the framebuffer +of the window it's pointing to, the window's clip region and so on. +It's intended to easily allow you to do your own pixel-level manipulation +of window contents. +<p> There should be no reason to modify this class. +<p> <h2> QWSSoundServer, Client +</h2> +<a name="12"></a><p> The Qt/Embedded server contains a simple sound player and mixer. Clients +can request the server play sounds specified as files. +<p> There should be no need to modify this class unless porting +Qt/Embedded to an operating system without a Linux-style <tt>/dev/dsp</tt>. +<p> <h2> <a href="qwswindow.html">QWSWindow</a> +</h2> +<a name="13"></a><p> This contains the server's notion of an individual top level window: +the region of the framebuffer it's allocated, the client that created it +and so forth. +<p> There should be no reason to modify this class. +<p> <h2> <a href="qwskeyboardhandler.html">QWSKeyboardHandler</a> » subtypes +</h2> +<a name="14"></a><p> This handles keyboard/button input. QWSKeyboardHandler is subclassed +to provide for reading <tt>/dev/tty</tt>, an arbitrary low-level USB event device +(for USB keyboards) and some PDA button devices. +<p> Modifying QWSKeyboardHandler would allow you to support different +types of keyboard (currently only a fairly standard US PC style +keyboard is supported); subclassing it is the preferred way to handle +non-pointer input devices. +<p> <h2> <a href="qwsmousehandler.html">QWSMouseHandler</a> » QWSCalibratedMouseHandler » mouse types +</h2> +<a name="15"></a><p> This handles mouse/touch-panel input. Descendants of QWSCalibratedMouseHandler +make use of filtering code which prevents 'jittering' of the pointer on +touchscreens; some embedded devices do this filtering in the kernel in +which case the driver doesn't need to inherit from QWSCalibratedMouseHandler. +<p> Subclassing QWSCalibratedMouseHandler is preferred for touch-panels without +kernel filtering; inheriting QWSMouseHandler is the way to add any other +type of pointing device (pen tablets, touchscreens, mice, trackballs +and so forth). +<p> <h2> QWSDisplay +</h2> +<a name="16"></a><p> This class exists only in the Qt/Embedded server and keeps track of +all the top-level windows in the system, as well as the keyboard and mouse. +<p> You would only want to modify this if making deep and drastic +modifications to Qt/Embedded window behaviour (alpha blended windows +for example). +<p> <h2> <a href="qwsserver.html">QWSServer</a> +</h2> +<a name="17"></a><p> This manages the Qt/Embedded server's Unix-domain socket connections to +clients. It sends and receives QWS protocol events and calls QWSDisplay +in order to do such things as change the allocation region of windows. +<p> The only reason to modify this would be to use something other than +some sort of socket-like mechanism to communicate between Qt/Embedded +applications (in which case modify QWSClient too). If you have +something like Unix domain sockets, modify QWSSocket/QWSServerSocket +instead. Don't add extra QWS events to communicate between +applications, use QCOP instead. +<p> <h2> QWSClient +</h2> +<a name="18"></a><p> This encapsulates the client side of a Qt/Embedded connection and can +marshal and demarshal events. +<p> There should be no reason to modify this except to use something +radically different from Unix domain sockets to communicate between +Qt/Embedded applications. +<p> <h2> QWSDisplayData +</h2> +<a name="19"></a><p> This manages a client's QWSClient, reading and interpreting events +from the QWS server. It connects to the QWS server on application +startup, getting information about the framebuffer and creating the +memory manager. Other information about the framebuffer comes directly +from <tt>/dev/fb</tt> in QLinuxFbScreen. +<p> There should be no reason to modify this. +<p> <h2> QWSCommands +</h2> +<a name="20"></a><p> These encapsulate the data sent to and from the QWS server. +<p> There should be no reason to modify them. +<p> <h2> <a href="qcopchannel.html">QCopChannel</a> +</h2> +<a name="21"></a><p> QCop is a simple IPC mechanism for communication between Qt/Embedded +applications. String messages with optional binary data can be sent +to different channels. +<p> The mechanism itself is designed to be bare-bones in order for users +to build whatever mechanism they like on top of it. +<p> <h2> QWSManager +</h2> +<a name="22"></a><p> This provides Qt/Embedded window management, drawing a title bar +and handling user requests to move, resize the window and so on. +<p> There should be no reason to modify it but you should subclass it +if you want to modify window behaviour (point to click versus +focus follows mouse, for instance). +<p> <h2> <a href="qwsdecoration.html">QWSDecoration</a> +</h2> +<a name="23"></a><p> Descendants of this class are different styles for the Qt/Embedded +window manager, for instance QWSWindowsDecoration draws Qt/Embedded +window frames in the style of Windows CE. +<p> Subclass it in order to provide a new window manager appearance (the +equivalent of a Windows XP or Enlightenment theme). +<p> <h2> QWSPropertyManager +</h2> +<a name="24"></a><p> This provides the QWS client's interface to the QWS property system +(a simpler version of the X property system, it allows you to attach +arbitrary data to top-level windows, keyed by an integer). +<p> There should be no reason to modify it. +<p> <h2> QWSRegionManager +</h2> +<a name="25"></a><p> Used by both client and server to help manage top-level window regions. +<p> There should be no reason to modify it. +<p> <h2> QWSSocket, QWSServerSocket +</h2> +<a name="26"></a><p> Provides Unix-domain sockets. +<p> Modify this if you're porting to a non-Unix OS but have something +analogous to Unix-domain sockets (a byte-oriented, reliable, ordered +transmission mechanism, although you can probably implement it with +something like a message queue as well). +<p> +<!-- eof --> +<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>Qt 3.3.8</div> +</table></div></address></body> +</html> |