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14<h1 align="left">G2S_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 G2S_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; <SPAN class="argument">ev1</SPAN> &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; <SPAN class="argument">ev2</SPAN> &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 <CODE>ev1</CODE> or <CODE>ev2</CODE> is greater than 16, the alpha-blending coefficient is set to 16.<BR><BR>Alpha blending will be performed using the sub 2D Engine if the second target plane immediately follows the first target plane. 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="G2S_BlendNone.html">G2S_BlendNone</A>, <A href="G2S_SetBlendBrightness.html">G2S_SetBlendBrightness</A>, <A href="G2S_SetBlendBrightnessExt.html">G2S_SetBlendBrightnessExt</A>, <A href="G2S_ChangeBlendAlpha.html">G2S_ChangeBlendAlpha</A>, <A href="G2S_ChangeBlendBrightness.html">G2S_ChangeBlendBrightness</A></CODE></P>
94<H2>Revision History</H2>
95<P>2008/10/30 Added description of the alpha-blending coefficients.</P>
96<P>2004/02/09 Initial version.</P>
97<hr><p>CONFIDENTIAL</p></body>
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