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14<h1 align="left">G2_SetBlendAlpha <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<PRE>
20<CODE>#include &lt;nitro/gx/g2.h&gt;</CODE><BR>
21<CODE>void G2_SetBlendAlpha(<BR>    int plane1 /* GXBlendPlaneMask */,<BR>    int plane2 /* GXBlendPlaneMask */,<BR>    int ev1,<BR>    int ev2<BR>);</CODE></PRE></dd>
22</dl><h2>Arguments</h2>
23
24<table border="1" width="100%">
25
26    <tr>
27<td width="13%"><em><strong><font face="Courier New">plane1</font></strong></em></td>
28<td width="87%">Selects the first target plane for blending (result of logical OR with <CODE>GXBlendPlaneMask</CODE> type values)</td>
29  </tr>
30    <TR>
31<TD><em><strong><font face="Courier New">plane2</font></strong></em></TD>
32<TD>Selects the second target plane for blending (result of logical OR with <CODE>GXBlendPlaneMask</CODE> type values)</TD>
33    </TR>
34    <TR>
35<TD><em><strong><font face="Courier New"><em><strong><code>ev1</code></strong></em>&nbsp;&nbsp;</font></strong></em></TD>
36<TD>alpha-blending coefficient for the first target screen (0 &le; <em><strong><code>ev1</code></strong></em> &le; 31)</TD>
37    </TR>
38    <TR>
39<TD><em><strong><font face="Courier New"><em><strong><code>ev2</code></strong></em>&nbsp;&nbsp;</font></strong></em></TD>
40<TD>alpha-blending coefficient for the second target screen (0 &le; <em><strong><code>ev2</code></strong></em> &le; 31)</TD>
41    </TR>
42  </table>
43<h2>Return Values</h2>
44<p>None.</p>
45<H2>Description</H2>
46<P>If the value of <SPAN class="argument">ev1</SPAN> or <SPAN class="argument">ev2</SPAN> is greater than 16, the alpha-blending coefficient is set to 16.<BR><BR>This function performs alpha-blending when the second target screen immediately follows the first target screen. You cannot specify a backdrop screen for the first target screen. Even if no OBJ is specified in the first target screen, alpha-blending is performed on the translucent OBJ, bitmap OBJ, and 3D screen.
47</P>
48<TABLE border="1">
49  <TBODY>
50    <TR>
51<TD width="30%"><CODE>GX_BLEND_PLANEMASK_NONE</CODE></TD>
52<TD>No plane is specified.</TD>
53    </TR>
54    <TR>
55<TD><CODE>GX_BLEND_PLANEMASK_BG0</CODE></TD>
56<TD>Specifies BG0.</TD>
57    </TR>
58    <TR>
59<TD><CODE>GX_BLEND_PLANEMASK_BG1</CODE></TD>
60<TD>Specifies BG1.</TD>
61    </TR>
62    <TR>
63<TD><CODE>GX_BLEND_PLANEMASK_BG2</CODE></TD>
64<TD>Specifies BG2.</TD>
65    </TR>
66    <TR>
67<TD><CODE>GX_BLEND_PLANEMASK_BG3</CODE></TD>
68<TD>Specifies BG3.</TD>
69    </TR>
70    <TR>
71<TD><CODE>GX_BLEND_PLANEMASK_OBJ</CODE></TD>
72<TD>Specifies OBJs.</TD>
73    </TR>
74    <TR>
75<TD><CODE>GX_BLEND_PLANEMASK_BD</CODE></TD>
76<TD>Specifies the backdrop plane.</TD>
77    </TR>
78  </TBODY>
79</TABLE>
80<P>The following indicates the type definition for <code>GXBlendPlaneMask</code> types.</P>
81<PRE><CODE>typedef enum
82{
83    GX_BLEND_PLANEMASK_NONE = 0x0000,
84    GX_BLEND_PLANEMASK_BG0 = 0x0001,
85    GX_BLEND_PLANEMASK_BG1 = 0x0002,
86    GX_BLEND_PLANEMASK_BG2 = 0x0004,
87    GX_BLEND_PLANEMASK_BG3 = 0x0008,
88    GX_BLEND_PLANEMASK_OBJ = 0x0010,
89    GX_BLEND_PLANEMASK_BD = 0x0020
90}
91GXBlendPlaneMask;</CODE></PRE>
92<h2>See Also</h2>
93<P><CODE><A href="G2_BlendNone.html">G2_BlendNone</A>, <A href="G2_SetBlendBrightness.html">G2_SetBlendBrightness</A>, <A href="G2_SetBlendBrightnessExt.html">G2_SetBlendBrightnessExt</A>, <A href="G2_ChangeBlendAlpha.html">G2_ChangeBlendAlpha</A>, <A href="G2_ChangeBlendBrightness.html">G2_ChangeBlendBrightness</A></CODE></P>
94<H2>Revision History</H2>
95<P>2008/10/30 Added description of the alpha-blending coefficients.</P>
96<P>2006/04/21 Added description.</P>
97<P>2004/01/19 Initial version.</P>
98<hr><p>CONFIDENTIAL</p></body>
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