--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Symbian3/SDK/Source/GUID-2C443E6F-BC3D-5252-8098-9F850AA88A35.dita	Wed Mar 31 11:11:55 2010 +0100
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+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->
+<!-- This component and the accompanying materials are made available under the terms of the License 
+"Eclipse Public License v1.0" which accompanies this distribution, 
+and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->
+<!-- Initial Contributors:
+    Nokia Corporation - initial contribution.
+Contributors: 
+-->
+<!DOCTYPE concept
+  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
+<concept id="GUID-2C443E6F-BC3D-5252-8098-9F850AA88A35" xml:lang="en"><title>Window
+Server Component Overview</title><shortdesc>The Window Server manages the use of the screen and input devices
+by applications and controls and co-ordinates access. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
+<section id="GUID-4BE363E2-E630-462D-A958-721B3636792E"><title>Architecture</title> <p>The
+architecture of the Window Server varies depending on whether you are using
+the <xref href="GUID-D93978BE-11A3-5CE3-B110-1DEAA5AD566C.dita">ScreenPlay (NGA)</xref> or <xref href="GUID-F64E6551-670E-5E12-8103-DE504D3EC94F.dita">non-ScreenPlay</xref> variant.
+However, with a few exceptions, the client-side API is the same in both variants.
+Both variants use an improved version of the Window Server, sometimes known
+as <codeph>WSERV2</codeph>, which was introduced in Symbian^2 (Symbian OS
+v9.4). </p> <p>The following diagram provides an overview of the Window Server
+architecture in ScreenPlay. </p> <fig id="GUID-80DA5DEB-019E-5CE3-812E-496A1D713FFB">
+<title>              The Window Server in ScreenPlay            </title>
+<image href="GUID-1635E243-BDC9-55D8-8913-0D2DB622B22C_d0e192309_href.png" placement="inline"/>
+</fig> <p>Below we list some of the key features of the Window Server, including
+differences between the two architectures. The term <b>surface</b> is used
+in ScreenPlay for a hardware-independent memory buffer for holding an image
+or part of a scene. The <b>UI surface</b> is a special surface onto which
+the Window Server renders all of the UI content. It is created automatically
+during system start up. An <b>external surface</b> is any other surface—for
+example, a surface that holds a video or to which OpenGL ES content is rendered. </p> <ul>
+<li id="GUID-A56D68E9-99E0-528A-9DDD-977BECE50A45"><p>The Window Server has
+a render stage framework, which enables the last stage of the Window Server
+rendering to be customizable through plug-ins called <b> render stages</b>.
+These can be chained to form a rendering pipeline, which takes the drawing
+operations that are produced by the Window Server and ultimately passes them
+to the UI surface. Render stages can selectively filter, modify, or redirect
+the draw operation stream, as required—for example, to perform transition
+effects (TFX). </p> </li>
+<li id="GUID-A6589F28-B8B5-5FBA-B241-6E526D6A9BF1"><p>In ScreenPlay, composition
+takes place in two stages. First, the render stages render the drawing to
+the UI surface. Then the composition engine combines the UI surface and any
+external surfaces into elements (sometimes called <b>layers</b>) and composes
+them to the screen. This enables the composition to be performed in software
+or hardware accelerator chips. </p> </li>
+<li id="GUID-BA8D10A1-F0CB-56F7-817B-F1425AC1DA56"><p>In the non-ScreenPlay
+variant, the concept of surfaces is not used and the Window Server composes
+directly onto the <b>frame buffer</b> which is then displayed on the screen. </p> </li>
+<li id="GUID-FC88013B-E5A4-5DD6-9906-A526D137CF43"><p>There are differences
+in the plug-in framework APIs in the two architectures. In addition, in ScreenPlay,
+fading effects are implemented by using render stages, whereas when ScreenPlay
+is not enabled they are implemented by using a separate fader plug-in type
+(not shown on the diagram). </p> </li>
+<li id="GUID-86A8FB36-B9DF-50F2-AE0B-798D717899A6"><p>In ScreenPlay, the Window
+Server provides advanced pointer features, such as support for multiple pointers
+and proximity and pressure coordinates. The non-ScreenPlay variant does not
+provide this support. </p> </li>
+<li id="GUID-46123A93-AF91-5FAB-995E-CDEAE9C8B961"><p>ScreenPlay provides
+support for externally connected displays, such as TV-out. The non-ScreenPlay
+variant considers the size of each display to be fixed. However, for High-Definition
+Multimedia Interface (HDMI) and composite video connectors, there are a range
+of resolutions that can change dynamically. ScreenPlay provides an optional
+feature that supports switching between resolutions at runtime and notifications
+to Window Server clients when there are changes to the resolution and connectedness. </p> </li>
+</ul> </section>
+<section id="GUID-2459A480-EC83-4595-97AA-D090331C9A88"><title>Building the
+ScreenPlay and non-ScreenPlay variants</title> <p>To build the ScreenPlay
+version of the Window Server components, declare the following macros in the <filepath>Symbian_OS.hrh</filepath> file. </p><codeblock xml:space="preserve">SYMBIAN_BUILD_GCE
+SYMBIAN_GRAPHICS_BUILD_OPENWF_WSERV
+</codeblock><p>This causes the ScreenPlay versions of the components in the
+Graphics package to be built in addition to the non-ScreenPlay components.
+Specifically the <codeph>SYMBIAN_BUILD_GCE</codeph> macro causes the ScreenPlay
+version of the Window Server to be built. This means that the <filepath>w32_nga.mmp</filepath> and <filepath>wserv_nga.mmp</filepath> files
+are built. These define a second macro, <codeph>SYMBIAN_GRAPHICS_GCE</codeph>,
+which causes the ScreenPlay Window Server classes to be built. </p> <p>To include the ScreenPlay versions when building
+ROM, use the <codeph>SYMBIAN_GRAPHICS_USE_GCE</codeph> flag. </p> </section>
+<section id="GUID-BEBE7D33-06C7-4B07-837E-9E67633EEFBF"><title>Selecting the
+ScreenPlay variant in the emulator</title><p>To select the ScreenPlay version
+of the component in the emulator, add the following line to the <filepath>epoc.ini</filepath> file: </p> <codeblock id="GUID-E0A64D1F-19B8-5002-8031-06E58AAE0055" xml:space="preserve">SYMBIAN_GRAPHICS_USE_GCE ON</codeblock></section>
+<section id="GUID-F13720C7-A6E1-4A3F-ACAF-10BEF6D2229F"><title>Executables</title> <p>This
+section lists the main Window Server executables. For clarity, these are divided
+into three groups. </p> <p><b>Window Server executable and client-side libraries </b> </p> <table id="GUID-E68F0783-FE52-55F3-8140-0FD527E91775">
+<tgroup cols="3"><colspec colname="col0"/><colspec colname="col1"/><colspec colname="col2"/>
+<thead>
+<row>
+<entry>Executable</entry>
+<entry>LIB</entry>
+<entry>Description</entry>
+</row>
+</thead>
+<tbody>
+<row>
+<entry><p> <filepath>wserv_nga.exe</filepath>  </p> </entry>
+<entry><p> </p> </entry>
+<entry><p>The ScreenPlay version of the Window Server. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>wserv_nonnga.exe</filepath>  </p> </entry>
+<entry><p> </p> </entry>
+<entry><p>The non-ScreenPlay version of the Window Server. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>ws32_nga.dll</filepath>  </p> </entry>
+<entry><p> <filepath>ws32.lib</filepath>  </p> </entry>
+<entry><p>The Window Server client-side API library for the ScreenPlay variant.
+See <xref href="GUID-DC5E8C7D-D697-53E8-87F4-344301430E61.dita">Window Server Client-Side
+Library</xref>. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>ws32_nonnga.dll</filepath>  </p> </entry>
+<entry><p> <filepath>ws32.lib</filepath>  </p> </entry>
+<entry><p>The Window Server client-side API library for the non-ScreenPlay
+variant. See <xref href="GUID-DC5E8C7D-D697-53E8-87F4-344301430E61.dita">Window
+Server Client-Side Library</xref>. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>wsgraphicdrawer_nga.dll</filepath>  </p> </entry>
+<entry><p> <filepath>wsgraphicdrawer.lib </filepath>  </p> </entry>
+<entry><p>The server-side base classes for Window Server plug-ins in the ScreenPlay
+variant. The plug-ins include graphic drawer plug-ins (which are also known
+as Content Rendering Plug-ins or CRPs) and render stage plug-ins. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>wsgraphicdrawer_nonnga.dll</filepath>  </p> </entry>
+<entry><p> <filepath>wsgraphicdrawer.lib </filepath>  </p> </entry>
+<entry><p>The server-side base classes for Window Server plug-ins in the non-ScreenPlay
+variant. The plug-ins include graphic drawer plug-ins (which are also known
+as Content Rendering Plug-ins or CRPs) and render stage and fader plug-ins. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>remotegc_nga.dll </filepath>  </p> </entry>
+<entry><p> <filepath>remotegc.lib </filepath>  </p> </entry>
+<entry><p>The client-side API library for remote graphic contexts in ScreenPlay.
+Remote graphic contexts store draw operations so that they can be played back
+later. It is "remote" because the draw operations are generally played back
+in a different location from where they are stored. For example, the draw
+operations are frequently stored on the client side and then a transformation
+engine uses them on the server side to make an effect. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>remotegc_nonnga.dll </filepath>  </p> </entry>
+<entry><p> <filepath>remotegc.lib </filepath>  </p> </entry>
+<entry><p>The client-side API library for remote graphic contexts in the non-ScreenPlay
+variant. This has a similar role as in ScreenPlay. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>profilerkeys.dll </filepath>  </p> </entry>
+<entry/>
+<entry><p>Window Server profiling hotkeys library in both ScreenPlay and non-ScreenPlay
+variants. </p> </entry>
+</row>
+</tbody>
+</tgroup>
+</table> <p><b>Logging libraries </b> </p> <table id="GUID-C233B864-B909-5C00-B90A-7C78F3D02AFC">
+<tgroup cols="2"><colspec colname="col0"/><colspec colname="col1"/>
+<thead>
+<row>
+<entry>Executable</entry>
+<entry>Description</entry>
+</row>
+</thead>
+<tbody>
+<row>
+<entry><p> <filepath>dlog.dll </filepath>  </p> </entry>
+<entry><p>On-screen logging library </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>dlogfl.dll </filepath>  </p> </entry>
+<entry><p>File logging library </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>dlogrd.dll </filepath>  </p> </entry>
+<entry/>
+</row>
+<row>
+<entry><p> <filepath>dlogsr.dll </filepath>  </p> </entry>
+<entry><p>Serial logging library </p> </entry>
+</row>
+</tbody>
+</tgroup>
+</table> <p><b>Plug-ins </b> </p> <table id="GUID-E71B0099-14D9-5C44-99FA-1DDB535EB7BF">
+<tgroup cols="3"><colspec colname="col0"/><colspec colname="col1"/><colspec colname="col2"/>
+<thead>
+<row>
+<entry>Executable</entry>
+<entry>Variant</entry>
+<entry>Description</entry>
+</row>
+</thead>
+<tbody>
+<row>
+<entry><p> <filepath>10281922.dll</filepath>  </p> </entry>
+<entry><p>Both </p> </entry>
+<entry><p>This is a standard reference CRP. This type of plug-in is called
+a <i>CWsGraphics</i> ECOM plug-in. Device creators can replace this component. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>2001b70b.dll</filepath>  </p> </entry>
+<entry><p>Non-ScreenPlay </p> </entry>
+<entry><p>This is a prototype reference render stage ECOM plug-in for the
+non-ScreenPlay variant. This type of plug-in is called a <i>CWsPlugin</i>. </p> <p>Note:
+The ScreenPlay render stage ECOM plug-in is delivered in the Window Server
+Plugins component. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>10285c4a.dll </filepath>  </p> </entry>
+<entry><p>ScreenPlay </p> </entry>
+<entry><p>This is a reference ScreenPlay surface-based CRP. Device creators
+can replace this component. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>samplegraphicsurface.dll </filepath>  </p> </entry>
+<entry><p>ScreenPlay </p> </entry>
+<entry><p>Sample ScreenPlay CRP (<i>CWsGraphics</i>) that demonstrates placing
+a surface. </p> </entry>
+</row>
+<row>
+<entry><p> <filepath>w32stdgraphic.dll </filepath>  </p> </entry>
+<entry><p>Both </p> </entry>
+<entry><p>Sample CRP (<i>CWsGraphics</i>). </p> </entry>
+</row>
+</tbody>
+</tgroup>
+</table> </section>
+<section id="GUID-439B39AD-4184-4928-BF35-ABAB94A89400"><title>Typical uses</title> <ul>
+<li id="GUID-BF47989B-D205-5ED8-BBCF-44B099E15C97"><p>Application developers
+use the <xref href="GUID-DC5E8C7D-D697-53E8-87F4-344301430E61.dita">client-side
+library</xref> to control windows in their applications and respond to key
+and pointer events. </p> </li>
+<li id="GUID-51A64C2E-C689-5765-8455-02C6350E4E88"><p>Testers and application
+developers use the <xref href="GUID-6E8807F5-9CC0-5A70-8182-22230D43AA9E.dita">logging
+mechanism</xref> to log Window Server events when developing and testing their
+code. </p> </li>
+<li id="GUID-139581CB-1185-569E-878D-58088230CCE8"><p>Device creators create
+Content Rendering Plug-ins (CRPs) for showing customized content on the screen. </p> </li>
+<li id="GUID-75EE03DE-0F78-5114-BCB9-8DD648A7C3A3"><p>Device creators who
+use ScreenPlay, can create render stage plug-ins. These enable the output
+of the Window Server to be combined with auxiliary software subsystems (such
+as a transition effect engine) and hardware-accelerated drawing (for example,
+using OpenVG). </p> </li>
+<li id="GUID-E712A357-5797-5291-829E-C054463FD286"><p>Device creators use
+the <xref href="GUID-1D529BDC-6665-58E2-AB3F-7023D8A84F69.dita">wsini.ini file</xref> to
+configure the Window Server to suit the specific requirements of the particular
+device. </p> </li>
+</ul> </section>
+</conbody><related-links>
+<link href="GUID-0C4B86B5-530A-5839-86C1-46E7ABE281E0.dita"><linktext>Window Server
+Component</linktext></link>
+
+
+</related-links></concept>
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