Symbian3/SDK/Source/GUID-F64E6551-670E-5E12-8103-DE504D3EC94F.dita
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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-F64E6551-670E-5E12-8103-DE504D3EC94F" xml:lang="en"><title>The
+Non-ScreenPlay Graphics Architecture</title><shortdesc>ScreenPlay provides improved support for graphics hardware acceleration
+and some other new features. However, it is possible to use the Symbian platform
+without enabling ScreenPlay. This is called the non-ScreenPlay variant (sometimes
+referred to as the <b>non-NGA</b> variant). This topic provides an introduction
+to the graphics architecture when ScreenPlay is <b>not</b> enabled. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
+<p>The following diagram shows the non-ScreenPlay architecture. It includes
+the components in the Graphics package and some closely related components
+in other packages. </p>
+<fig id="GUID-060B8747-36A8-5F2A-BE82-0F637381673A">
+<title>The Symbian Foundation non-ScreenPlay graphics architecture </title>
+<image href="GUID-1EC68F99-C383-5D3A-BAE9-52AF530F8445_d0e191485_href.png" placement="inline"/>
+</fig>
+<p>The software model is as follows: </p>
+<ul>
+<li id="GUID-8BDB2015-C8FD-51EC-AB19-A55C55DD6D4B"><p>The Hardware Adaptation
+Layer (HAL) consists of the frame buffer and basic attributes. All processes
+have equal access to the frame buffer and can both read and write to it. </p> </li>
+<li id="GUID-06209922-9276-5843-95ED-CCE01A96A67C"><p>The Screen Driver provides
+simple pixel, scan-line and bitmap operations. The Screen Driver has the same
+interface for both bitmaps and the frame buffer. Hardware manufacturers can
+adapt the Screen Driver to suit the available hardware. </p> </li>
+<li id="GUID-333C52F6-5B6C-5212-8286-B344749550B5"><p>The BitGDI component
+provides support for higher-level geometric primitives and text. The BitGDI
+component is implemented in terms of Screen Driver operations. All BitGDI
+rendering operations are synchronous. </p> </li>
+<li id="GUID-B542796F-47AE-5B8A-976A-446315EC6550"><p>The Window Server multiplexes
+access to the screen and provides a BitGDI-like interface. </p> </li>
+<li id="GUID-81912D86-0CF6-5399-84FF-904E15BA8B50"><p>The Window Server provides
+Direct Screen Access (DSA) support for applications that require high frame
+rates (such as video and games) to bypass the Window Server and write to the
+frame buffer directly. However, some interaction with the Window Server is
+needed to prevent the application from drawing over other application's data. </p> </li>
+</ul>
+<p>In addition, the non-ScreenPlay architecture provides support for EGL,
+OpenGL and OpenVG. </p>
+<p>The following diagram shows the rendering stack in the non-ScreenPlay variant. </p>
+<fig id="GUID-4A245007-BE0A-5DD6-A3D5-CAD9A16E0540">
+<title>The rendering stack in the non-ScreenPlay variant</title>
+<image href="GUID-A51AB0B8-A13D-52D0-BEF8-435F76B30941_d0e191530_href.png" placement="inline"/>
+</fig>
+
+<p>Although DSA provides a solution for applications that require high frame
+rates, the non-ScreenPlay architecture has limitations when used on graphics
+accelerated hardware and non-uniform memory models. The architecture may require
+the copying of buffers between CPU and GPU memory as shown in the following
+diagram. ScreenPlay provides a solution that requires less copying of buffers
+in this type of use case. </p>
+<fig id="GUID-0EAF51D1-173E-52E2-8E28-C5FB7F6F9BD0">
+<title> Example non-uniform memory, non-ScreenPlay hardware model </title>
+<image href="GUID-AB35BA46-87DB-59F0-9342-75550AD338B7_d0e191542_href.png" placement="inline"/>
+</fig>
+</conbody><related-links>
+<link href="GUID-D93978BE-11A3-5CE3-B110-1DEAA5AD566C.dita"><linktext>The ScreenPlay
+Architecture</linktext></link>
+<link href="GUID-EF62BF88-3687-505D-8BD7-EEDF36246E56.dita"><linktext>Graphics
+Hardware Acceleration</linktext></link>
+<link href="GUID-99BC101A-9466-59EE-B5C9-7622BAF6E6FF.dita"><linktext>Graphics
+Concepts</linktext></link>
+</related-links></concept>
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