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<concept id="GUID-82B0B4B9-6BC2-5BEF-B3B0-D57AC57F8D8A" xml:lang="en"><title>Graphics

Resource Component Overview</title><shortdesc>The Graphics Resource component is not available on all systems.

When present, together with the Graphics Resource Adaptation component, it

provides an abstraction layer for the memory management of graphics data,

both pixel data and non-pixel data (such as OpenVG command lists). The Graphics

Resource component is the generic part, which provides the client API, whereas

the Graphics Resource Adaptation component provides the adaptation part, which

device creators can adapt to suit their graphics acceleration hardware if

any is available. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p><b>Target audience</b>: Device creators.</p>

<note type="note">The Graphics Resource component is deprecated in Symbian^3

and will be removed in Symbian^4 (S^4). However, a new Graphics Resource Interface

component is planned for S^4. This new component will provide a similar but

reduced API that is optimized for sharing images across processes.</note>

<p>The <xref href="GUID-F2AF891D-A514-5743-B6F0-9271CE2A1775.dita">CBR package

name</xref> for the Graphics Resource component is <filepath>graphics_graphicsresource</filepath>. </p>

<section id="GUID-7DA9610F-B761-4328-8FA9-53A18E281538"><title>Key classes</title> <p>The following diagram shows the relationships

between the key classes. </p> <fig id="GUID-053684EB-72B6-5D02-863D-6F24391A61B1">

<title>              Key Graphics Resource component classes            </title>

</fig> <table id="GUID-DBC2BBC9-E6B0-5DC0-B6B7-1D4186F901D2">

<tgroup cols="2"><colspec colname="col0"/><colspec colname="col1"/>

<thead>

<row>

<entry>Class</entry>

<entry>Description</entry>

</row>

</thead>

<tbody>

<row>

<entry><p> <xref href="GUID-EDC0E03F-37F6-3BEC-8FF3-D03C3CDB949C.dita"><apiname>RSgImage</apiname></xref>  </p> </entry>

<entry><p>A handle to a reference-counted, two-dimensional pixel array that

can be used as a source or target for different rendering pipelines. Attributes

that are set at creation time define parameters such as the size, screen and

usage. These cannot be changed after creation. </p> <p>An image can be shared

between processes by passing its unique identifier. Alternatively it can be

created as process-specific and not shareable, which may have performance

advantages. </p> </entry>

</row>

<row>

<entry><p> <xref href="GUID-FCF750E4-526C-3789-89D8-DEF02BB7A5A7.dita"><apiname>RSgImageCollection</apiname></xref>  </p> </entry>

<entry><p>A handle to a reference-counted collection of images with the same

attributes which is allocated in such a way that it can be used with the <xref href="GUID-0DC3E5AA-1706-5255-ACD6-E7AB732E1095.dita">graphics composition components</xref>.

Clients can access each of the images in the collection individually through <xref href="GUID-EDC0E03F-37F6-3BEC-8FF3-D03C3CDB949C.dita"><apiname>RSgImage</apiname></xref> handles.

Interoperability with the <xref href="GUID-0DC3E5AA-1706-5255-ACD6-E7AB732E1095.dita">graphics

composition components</xref> is achieved by passing the surface identifier

returned by <codeph>RSgImageCollection::SurfaceId()</codeph> in calls to the

Composition Interface API or the Surface Update API. </p> </entry>

</row>

<row>

<entry><p> <xref href="GUID-6F23F34A-A0BE-349C-ADE7-61A5AEF48018.dita"><apiname>RSgDrawable</apiname></xref>  </p> </entry>

<entry><p>A handle to a reference-counted graphics resource that can be drawn

in different rendering pipelines—for example, DirectGDI or OpenVG. Instances

of <xref href="GUID-6F23F34A-A0BE-349C-ADE7-61A5AEF48018.dita"><apiname>RSgDrawable</apiname></xref> allow access to drawable resources created

using other APIs without knowing the concrete type of the resource. </p> </entry>

</row>

</tbody>

</tgroup>

</table> </section>

</conbody><related-links>

<link href="GUID-26E51AB0-C0FC-55EA-B747-C834E2D4FD27.dita"><linktext>Graphics

Resource Services Collection</linktext></link>

<link href="GUID-E2A886E1-39FD-517F-870E-3B1BCD49E8CD.dita"><linktext>Off-Screen

Rendering with DirectGDI Tutorial</linktext></link>

</related-links></concept>