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<concept id="GUID-4C166A49-31F7-5315-B797-F97DB52600BC" xml:lang="en"><title>Display Driver

Component</title><shortdesc>The Display Driver component (also known as the <b>Display Channel

Driver</b>) is new in Symbian^3 and is for use in ScreenPlay only. The Display

Driver component includes a reference implementation, which a composition

implementation can use to display the composited output on the screen without

tearing. However, the use of the Display Channel Driver is optional. Implementers

of the Composition Interface are not required to use it. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The Display Channel Driver provides the <xref href="GUID-7AE33C09-8CB2-335B-B2CC-76F437E3352E.dita"><apiname>RDisplayChannel</apiname></xref> API.

This provides methods that post double-buffered composition frame buffers

to the screen and set and get the screen rotation, resolution and other display

properties. <xref href="GUID-7AE33C09-8CB2-335B-B2CC-76F437E3352E.dita"><apiname>RDisplayChannel</apiname></xref> also allows composition surfaces

to be posted directly to the screen without being composited with other layers.

This is referred to as <b>fast path mode</b> and is typically used when a

video or game occupies the whole screen. The <xref href="GUID-7AE33C09-8CB2-335B-B2CC-76F437E3352E.dita"><apiname>RDisplayChannel</apiname></xref> API

uses the term <b>user buffers</b> for surfaces that are in fast path mode.</p>

<p><i>Note</i>: The Display Channel Driver does not replace the existing LCD

Driver, which is implemented as a standard kernel extension and is therefore

also known as the <b>LCD Extension</b>. This continues to be required and

provides support for legacy applications.</p>

</conbody><related-links>

<link href="GUID-8C22AF20-EE0E-5AD2-BEFD-FED5A7DBB09B.dita"><linktext>LCD Extension</linktext>

</link>

<link href="GUID-4797000B-B61D-5EF8-8C38-3159433C9C7B.dita"><linktext>Graphics

Hardware Drivers Collection</linktext></link>

</related-links></concept>