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<concept xml:lang="en" id="GUID-E007CDD5-4263-5020-BB6F-B39F44647519"><title>OpenVG Version Variability Point</title><shortdesc>The OpenVG Interface component provides header files for both OpenVG 1.0 and OpenVG 1.1. The OpenVG 1.0 headers are used by default. However, there is a variability point that can be used to change the header version. This allows a staged migration from OpenVG 1.0 to OpenVG 1.1. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody><p> <b>Variant</b>: <xref href="GUID-D93978BE-11A3-5CE3-B110-1DEAA5AD566C.dita">ScreenPlay</xref> and <xref href="GUID-F64E6551-670E-5E12-8103-DE504D3EC94F.dita">non-ScreenPlay</xref>. <b>Target audience</b>: Device creators. </p> <p>The variability point consists of adding the following <codeph>#define</codeph> identifiers to the system-wide OEM-specific variation HRH file. </p> <table id="GUID-8103B9D9-B24A-5D3A-B101-BF2D1CB7519E"><tgroup cols="2"><colspec colname="col0"/><colspec colname="col1"/><thead><row><entry><codeph>#define</codeph> Identifier</entry> <entry>Description</entry> </row> </thead> <tbody><row><entry><p> <codeph>__OPENVGHEADERS_USE_VG_1_1</codeph>  </p> </entry> <entry><p>Use this if you want to use the OpenVG 1.1 headers rather than the OpenVG 1.0 ones that are used by default. </p> </entry> </row> <row><entry><p> <codeph>OPENVG_RESTRICTED_TO_1_0</codeph>  </p> </entry> <entry><p>Use this if you have an OpenVG 1.1 implementation but want to use it through the OpenVG 1.0 headers, effectively hiding any API later than OpenVG 1.0. </p> </entry> </row> </tbody> </tgroup> </table> <p>The main <filepath>openvg.h</filepath> and <filepath>vgu.h</filepath> header files test whether these identifiers have been defined and redirects the header files to the appropriate version accordingly, like this: </p> <codeblock id="GUID-731F821E-1602-5A9B-8526-A7D67C115C22" xml:space="preserve">#if defined(__OPENVGHEADERS_USE_VG_1_1) &amp;&amp; !defined(OPENVG_RESTRICTED_TO_1_0)
#include &lt;VG/1.1/openvg.h&gt;
#else
#include &lt;VG/1.0/openvg.h&gt;
#endif
</codeblock> </conbody><related-links><link href="GUID-7EFBEEAD-3E74-5165-B305-313F7DE4BEB4.dita"><linktext>OpenVG Interface Component
                Overview</linktext> </link> <link href="GUID-20419A98-3787-5F10-9CAD-2BC5D7560776.dita"><linktext>OpenVG Porting Guide</linktext> </link> </related-links></concept>