PowerVR QScreen Driver+
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======================+
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+
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This QScreen plugin driver allows the QtOpenGl module to integrate with PowerVR+
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hardware from Imagination Technologies. Using this plugin, applications may use+
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QGLWidget & QGLPixelBuffer with OpenGL ES. The integration with PowerVR drivers+
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is built as two libraries: The actual QScreen plugin used by Qt (in the+
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pvreglscreen directory) and a WSEGL plugin for the PowerVR drivers (in the+
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QWSWSEGL directory).+
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+
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Qt/Embedded needs to be configured with the QT_QWS_CLIENTBLIT and+
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QT_NO_QWS_CURSOR defines.+
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+
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The PowerVR drivers provide the WSEGL plugin API to allow window systems such as+
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QWS to integrate correctly. In order to use the integration, the WSEGL plugin+
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(libpvrQWSWSEGL.so, usually installed into the Qt library directory) must be in+
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the LD library path. The PowerVR driver also needs to be told which WSEGL library+
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to use. This is done by creating/modifying /etc/powervr.ini:+
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+
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[default]+
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WindowSystem=libpvrQWSWSEGL.so+
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+
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Note: It is important that the /etc/powervr.ini file not contain ^M (Ctrl-M) DOS+
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end of line markers at the end of its lines. If ^M markers are present, then the+
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libpvrQWSWSEGL.so driver will not be loaded and the default null Linux driver+
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will be loaded silently instead.  Make sure that the end of line markers are+
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strictly Unix-style markers.+
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+
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+
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***************************************************************************+
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* IMPORTANT: To build the QScreen plugin and the WSEGL library it depends *+
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* on, the pvr2d.h, wsegl.h headers for your platform are required.  You   *+
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* can find a copy of these headers in src/3rdparty/powervr for SGX based  *+
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* platforms like the TI OMAP3xxx.  They probably will not work on MBX     *+
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* because of differences in the layout of certain PVR2D structures.       *+
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* You can tell Qt where to find the actual headers for your system by     *+
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* setting QMAKE_INCDIR_POWERVR in the mkspec.                             *+
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***************************************************************************+
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+
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When you start a Qt/Embedded application, you should modify the QWS_DISPLAY+
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environment variable to use the "powervr" driver instead of "LinuxFb".  For+
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example, if your original QWS_DISPLAY variable was:+
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+
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    LinuxFb:mmWidth40:mmHeight54:0+
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+
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then it should be changed to:+
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+
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    powervr:mmWidth40:mmHeight54:0+
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+
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To test the OpenGL ES integration, you can use the hellogl_es example and run it+
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on the device with:+
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+
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    hellogl_es -qws+
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+
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The driver also supports screen rotation if Qt is configured with the+
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-qt-gfx-transformed option and the QWS_DISPLAY variable is wrapped in a+
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"Transformed" declaration:+
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+
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    Transformed:powervr:mmWidth40:mmHeight54:Rot90:0+
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+
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Know Issues:+
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    * A QGLWidget may not have window decorations if it is a top-level window.+
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    * On some platforms, starting a QWS application after the system has been up+
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      for a long time may cause the driver to fail. This is due to fragmentation+
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      of main memory prevening older PowerVR drivers from allocating a contiguous+
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      region of phyical RAM for the GL surface.+
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