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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>