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14<h1 align="left">G3X_SetFog <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/g3x.h&gt;</CODE><BR>
21<CODE>void G3X_SetFog(
22    BOOL enable,<BR>    GXFogBlend fogMode,<BR>    GXFogSlope fogSlope,<BR>    int fogOffset<BR>);</CODE></PRE></dd>
23</dl><h2>Arguments</h2>
24
25<table border="1" width="100%">
26
27    <tr>
28      <TD width="109"><em><strong><font face="Courier New">enable</font></strong></em></TD>
29      <TD width="593">Sets whether fog is enabled</TD>
30    </tr>
31    <TR>
32      <TD><em><strong><font face="Courier New">fogMode</font></strong></em></TD>
33      <TD>Sets whether fog will be applied to color in addition to the a-value</TD>
34    </TR>
35    <TR>
36      <TD><em><strong><font face="Courier New">fogSlope</font></strong></em></TD>
37      <TD>Sets the gradient for applying fog</TD>
38    </TR>
39    <TR>
40      <TD><em><strong><font face="Courier New">fogOffset</font></strong></em></TD>
41      <TD>Sets the depth value where fog calculations start</TD>
42    </TR>
43  </table>
44<h2>Return Values</h2>
45<p>None.</p>
46<H2>Description</H2>
47<P>This function sets Fog to enable/disable and how fog is applied. The larger the last number in the <code>GXFogSlope</code> format symbol indicates more flexibility in how the fog is applied. That is to say, if this value is <code>x</code>, the depth value is applied from <em><strong><code>fogOffset</code></strong></em> to <em><strong><code>fogOffset</code></strong></em> + <code>x</code> and the fog gradually becomes denser (the index in the referenced fog table grows larger).
48</P>
49<TABLE border="1">
50  <TBODY>
51    <TR>
52      <TD width="30%"><CODE>GX_FOGBLEND_COLOR_ALPHA</CODE></TD>
53      <TD><CODE>Fog blending applied to the pixel's color value and &alpha;-value</CODE></TD>
54    </TR>
55    <TR>
56      <TD><CODE>GX_FOGBLEND_ALPHA</CODE></TD>
57      <TD><CODE>Fog blending applied only to the pixel's &alpha;-value</CODE></TD>
58    </TR>
59  </TBODY>
60</TABLE>
61<P></P>
62<TABLE border="1">
63  <TBODY>
64    <TR>
65      <TD width="30%"><CODE>GX_FOGSLOPE_0x8000</CODE></TD>
66      <TD>Fog becomes denser according to the depth value with a width of 0x8000</TD>
67    </TR>
68    <TR>
69      <TD><CODE>GX_FOGSLOPE_0x4000</CODE></TD>
70      <TD>Fog becomes denser according to the depth value with a width of 0x4000</TD>
71    </TR>
72    <TR>
73      <TD><CODE>GX_FOGSLOPE_0x2000</CODE></TD>
74      <TD>Fog becomes denser according to the depth value with a width of 0x2000</TD>
75    </TR>
76    <TR>
77      <TD><CODE>GX_FOGSLOPE_0x1000</CODE></TD>
78      <TD>Fog becomes denser according to the depth value with a width of 0x1000</TD>
79    </TR>
80    <TR>
81      <TD><CODE>GX_FOGSLOPE_0x0800</CODE></TD>
82      <TD>Fog becomes denser according to the depth value with a width of 0x0800</TD>
83    </TR>
84    <TR>
85      <TD><CODE>GX_FOGSLOPE_0x0400</CODE></TD>
86      <TD>Fog becomes denser according to the depth value with a width of 0x0400</TD>
87    </TR>
88    <TR>
89      <TD><CODE>GX_FOGSLOPE_0x0200</CODE></TD>
90      <TD>Fog becomes denser according to the depth value with a width of 0x0200</TD>
91    </TR>
92    <TR>
93      <TD><CODE>GX_FOGSLOPE_0x0100</CODE></TD>
94      <TD>Fog becomes denser according to the depth value with a width of 0x0100</TD>
95    </TR>
96    <TR>
97      <TD><CODE>GX_FOGSLOPE_0x0080</CODE></TD>
98      <TD>Fog becomes denser according to the depth value with a width of 0x0080</TD>
99    </TR>
100    <TR>
101      <TD><CODE>GX_FOGSLOPE_0x0040</CODE></TD>
102      <TD>Fog becomes denser according to the depth value with a width of 0x0040</TD>
103    </TR>
104    <TR>
105      <TD><CODE>GX_FOGSLOPE_0x0020</CODE></TD>
106      <TD>Fog becomes denser according to the depth value with a width of 0x0020</TD>
107    </TR>
108  </TBODY>
109</TABLE>
110<P>Below are the matrix format type definitions used in the argument.</P>
111<PRE><CODE>typedef enum
112{
113    GX_FOGBLEND_COLOR_ALPHA = 0,
114    GX_FOGBLEND_ALPHA = 1
115}
116GXFogBlend;
117
118typedef enum
119{
120    GX_FOGSLOPE_0x8000 = 0,
121    GX_FOGSLOPE_0x4000 = 1,
122    GX_FOGSLOPE_0x2000 = 2,
123    GX_FOGSLOPE_0x1000 = 3,
124    GX_FOGSLOPE_0x0800 = 4,
125    GX_FOGSLOPE_0x0400 = 5,
126    GX_FOGSLOPE_0x0200 = 6,
127    GX_FOGSLOPE_0x0100 = 7,
128    GX_FOGSLOPE_0x0080 = 8,
129    GX_FOGSLOPE_0x0040 = 9,
130    GX_FOGSLOPE_0x0020 = 10
131}
132GXFogSlope;</CODE></PRE>
133<h2>See Also</h2>
134<P><A href="G3X_SetFogColor.html"><code>G3X_SetFogColor</code></A>, <A href="G3X_SetFogTable.html"><code>G3X_SetFogTable</code></A></P>
135<H2>Revision History</H2>
136<P>2004/01/19 Initial version.</P>
137<hr><p>CONFIDENTIAL</p></body>
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