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14<h1 align="left">G3X_AlphaTest <img src="../../image/NTR.gif"align="middle"><img src="../../image/TWL.gif" align="middle"></H1>
15<H2>Syntax</H2>
16
17<dl>
18  <dd>
19<CODE>#include &lt;nitro/gx/g3x.h&gt;</CODE><BR>
20  <BR>
21  <CODE>void G3X_AlphaTest(BOOL enable, int ref);<BR></CODE></dd>
22</dl><h2>Arguments</h2>
23
24<table border="1" width="100%">
25
26    <tr>
27      <TD width="109"><em><strong><font face="Courier New">enable</font></strong></em></TD>
28      <TD width="593">Sets whether a-test occurs</TD>
29    </tr>
30    <TR>
31      <TD><em><strong><font face="Courier New">ref</font></strong></em></TD>
32      <TD>When the alpha-test is performed, pixels where alpha&lt;=<em><strong><code>ref</code></strong></em> will not be rendered</TD>
33    </TR>
34  </table>
35<h2>Return Values</h2>
36<p>None.</p>
37<H2>Description</H2>
38<P>This function controls the alpha-test. When <em><strong><code>enable</code></strong></em> is not <code>FALSE</code>, the alpha value of the fragment after texture blending is compared to <em><strong><code>ref</code></strong></em>. The fragment is not rendered if it is less than the set value. When <em><strong><code>enable</code></strong></em> is <code>FALSE</code>, alpha testing does not occur.<BR> <B>Caution:</B> A polygon (wire frame display) is not drawn when alpha=0 and <B><I>ref</I></B> is set as 31.</P>
39
40<h2>See Also</h2>
41<H2>Revision History</H2>
42<P>2004/01/19 Initial version.</P>
43<hr><p>CONFIDENTIAL</p></body>
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