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8<TITLE>GXSetDstAlpha</TITLE>
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11<H1 align="left">GXSetDstAlpha</H1>
12<H2>C Specification</H2>
13<DL>
14  <DD>
15<PRE><CODE>#include &lt;revolution/gx.h&gt;</CODE></PRE>
16  <DD>
17<PRE>void GXSetDstAlpha( <a href="../Enumerated_Types/GXBool.html">GXBool</a> enable, u8 alpha );</PRE>
18</DL>
19<H2>Arguments</H2>
20<TABLE border="1" cellpadding="3" cellspacing="0.1">
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23<TD width="120" valign="top" style="border: 1px solid" bgcolor="#ffffe8"><EM><STRONG><CODE>enable</FONT></STRONG></EM></TD>
24<TD width="520" style="border: 1px solid">When <code><em><strong>enable</strong></em>=GX_TRUE</code>, and the <a     href="GXSetPixelFmt.html">pixel format</a> in the frame buffer supports destination alpha, <code><em><strong>alpha</strong></em></code> will be written to the frame buffer.</TD>
25    </TR>
26    <TR>
27<TD width="120" valign="top" style="border: 1px solid" bgcolor="#ffffe8"><EM><STRONG><CODE>alpha</FONT></STRONG></EM></TD>
28<TD width="520" style="border: 1px solid">Constant alpha value.</TD>
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32<H2>Return Values</H2>
33<P>None.</P>
34<H2>Description</H2>
35<P>This function sets a constant alpha value for writing to the embedded frame buffer (EFB).&nbsp;To be effective, the EFB pixel type must have an alpha channel. For more information, see <code><a href="GXSetPixelFmt.html">GXSetPixelFmt</a></code>. The alpha compare process (see the <CODE><A href="../Tev/GXSetAlphaCompare.html">GXSetAlphaCompare</A></CODE> function) and the blend process (see the <A href="GXSetBlendMode.html"><CODE>GXSetBlendMode</CODE></A> function) use the input alpha (output from the last TEV stage), but when writing the pixel color, the constant <CODE><EM><STRONG>alpha</STRONG></EM></CODE> will replace the pixel alpha in the EFB.</P>
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38<H2>See Also</H2>
39<P><A href="GXSetPixelFmt.html"><CODE>GXSetPixelFmt</CODE></A></P>
40<H2>Revision History</H2>
41<P>2006/03/01 Initial version.</P>
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43<P>CONFIDENTIAL</p>
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