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diff --git a/doc/accel.doc b/doc/accel.doc deleted file mode 100644 index 3b7ac552a..000000000 --- a/doc/accel.doc +++ /dev/null @@ -1,140 +0,0 @@ -/**************************************************************************** -** -** Help with writing Qt/Embedded accelerated drivers -** -** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved. -** -** This file is part of the TQt GUI Toolkit. -** -** This file may be used under the terms of the GNU General -** Public License versions 2.0 or 3.0 as published by the Free -** Software Foundation and appearing in the files LICENSE.GPL2 -** and LICENSE.GPL3 included in the packaging of this file. -** Alternatively you may (at your option) use any later version -** of the GNU General Public License if such license has been -** publicly approved by Trolltech ASA (or its successors, if any) -** and the KDE Free TQt Foundation. -** -** Please review the following information to ensure GNU General -** Public Licensing requirements will be met: -** http://trolltech.com/products/qt/licenses/licensing/opensource/. -** If you are unsure which license is appropriate for your use, please -** review the following information: -** http://trolltech.com/products/qt/licenses/licensing/licensingoverview -** or contact the sales department at sales@trolltech.com. -** -** This file may be used under the terms of the Q Public License as -** defined by Trolltech ASA and appearing in the file LICENSE.QPL -** included in the packaging of this file. Licensees holding valid Qt -** Commercial licenses may use this file in accordance with the Qt -** Commercial License Agreement provided with the Software. -** -** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, -** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR -** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted -** herein. -** -**********************************************************************/ - -/*! -\page emb-accel.html - -\title Adding an accelerated graphics driver to Qt/Embedded - -Qt/Embedded has the capacity to make use of hardware accelerators. -To use a hardware accelerator for a PCI or AGP driver, you must -perform the following steps: - -\list 1 -\i -Define an accelerated descendant of QLinuxFbScreen. - -This should implement \c QVoodooScreen::connect() to map its -registers. Use \c qt_probe_bus to get a pointer to the PCI config -space. This is where you should check that you're being pointed to the -right device (using the PCI device/manufacturer ID information). Then -use PCI config space to locate your device's accelerator registers in -physical memory and mmap the appropriate region from \c /dev/mem. -There is no need to map the framebuffer, \c QLinuxFbScreen will do -this for you. Return \c FALSE if a problem occurs at any point. \c -QVoodooScreen::initDevice() will be called only by the QWS server and -is guaranteed to be called before any drawing is done (and so is a -good place to set registers to known states). \c connect() will be called -by every connecting client. - -\i -Define an accelerated descendant of QGfxRaster. - -This is where the actual drawing code goes. Anything not implemented -in hardware can be passed back to \c QGfxRaster to do in software. Use -the optype variable to make sure that accelerated and unaccelerated -operations are synchronised (if you start drawing via software into an -area where the hardware accelerator is still drawing then your drawing -operations will appear to be in the wrong order). optype is stored in -shared memory and is set to 0 by unaccelerated operations; accelerated -operations should set it to 1. When a software graphics operation is -requested and optype is 1, \c QGfxRaster::sync() is called; you should -provide your own implementation of this that waits for the graphics -engine to go idle. lastop is also available for optimisation and is -stored in the shared space: this will not be set by the software-only -\c QGfx and can be used to store the type of your last operation (e.g. -drawing a rectangle) so that part of the setup for the next operation -can be avoided when many of the same operations are performed in -sequence. - -All drawing operations should be protected via a \c QWSDisplay::grab() -before any registers, lastop or optype are accessed, and \c -ungrabbed() at the end. This prevents two applications trying to -access the accelerator at once and possibly locking up the machine. -It's possible that your source data is not on the graphics card so you -should check in such cases and fall back to software if necessary. -Note that \c QGfxRaster supports some features not directly supported -by QPainter (for instance, alpha channels in 32-bit data and -stretchBlt's). These features are used by Qt; stretchBlt speeds up \c -QPixmap::xForm() and \c drawPixmap() into a transformed \c QPainter, -alpha channel acceleration is supported for 32-bit pixmaps. - -\i -If you wish, define an accelerated descendant of \c QScreenCursor. \c -restoreUnder(), \c saveUnder(), \c drawCursor() and \c draw() should -be defined as null operations. Implement \c set(), \c move(), \c -show() and \c hide(). 4KB is left for your cursor at the end of the -visible part of the framebuffer (i.e. at (width*height*depth)/8 ) - -\i -Implement \c initCursor() and \c createGfx() in your \c QScreen -descendant. Implement \c useOffscreen() and return \c TRUE if you can -make use of offscreen graphics memory. - -\i -Implement a small function \c qt_get_screen_mychip(), which simply -returns a new \c QMychipScreen - -\i -Add your driver to the DriverTable table in \c qgfxraster_qws.cpp, -e.g. -\code -{ "MyChip", qt_get_screen_mychip,1 }, -\endcode - -The first parameter is the name used with QWS_DISPLAY to request your -accelerated driver. - -\i -To run with your new driver, -\code -export QWS_DISPLAY=MyChip -\endcode -(optionally MyChip:/dev/fb\<n\> to request a different Linux -framebuffer than \c /dev/fb0), then run the program - -\endlist - -If your driver is not PCI or AGP you'll need to inherit \c QScreen -instead of \c QLinuxFbScreen and implement similar functionality to \c -QLinuxFbScreen, but otherwise the process should be similar. The most -complete example driver is \c qgfxmach64_qws.cpp; \c -qgfxvoodoo_qws.cpp may provide a smaller and easier-to-understand -driver. - -*/ |