1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
2<html>
3
4<head>
5<META http-equiv="Content-Type" content="text/html; charset=windows-1252">
6<META name="GENERATOR" content="IBM WebSphere Studio Homepage Builder Version 8.0.0.0 for Windows">
7<META http-equiv="Content-Style-Type" content="text/css">
8<title>G3_Perspective</title>
9<LINK rel="stylesheet" href="../../css/nitro.css" type="text/css">
10</head>
11
12<body>
13
14<h1 align="left">G3_Perspective <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/g3_util.h&gt;</CODE><BR>
21<CODE>void G3_Perspective(
22    fx32 fovySin,
23    fx32 fovyCos,
24    fx32 aspect,
25    fx32 n,
26    fx32 f,
27    MtxFx44 * mtx
28);</CODE></PRE></dd>
29</dl><h2>Arguments</h2>
30<TABLE border="1" width="100%">
31  <TBODY>
32    <TR>
33      <TD width="190"><em><strong><font face="Courier New">fovySin</font></strong></em></TD>
34      <TD width="512">Sine value of (the field-of-view angle in y-direction)/2</TD>
35    </TR>
36    <TR>
37      <TD width="190"><em><strong><font face="Courier New">fovyCos</font></strong></em></TD>
38      <TD width="512">Cosine value of (the field-of-view angle in y-direction)/2</TD>
39    </TR>
40    <TR>
41      <TD><em><strong><font face="Courier New">aspect</font></strong></em></TD>
42      <TD>Ratio of width of view field to height of view field (aspect ratio: width/height of the field of view)</TD>
43    </TR>
44    <TR>
45      <TD><em><strong><font face="Courier New">n</font></strong></em></TD>
46      <TD>Distance from viewpoint to the near clipping plane</TD>
47    </TR>
48    <TR>
49      <TD><em><strong><font face="Courier New">f</font></strong></em></TD>
50      <TD>Distance from viewpoint to the far clipping plane</TD>
51    </TR>
52    <TR>
53      <TD width="190"><em><strong><font face="Courier New">mtx</font></strong></em></TD>
54      <TD width="512">Pointer to a 4x4 matrix.</TD>
55    </TR>
56  </TBODY>
57</TABLE>
58<h2>Return Values</h2>
59<p>None.</p>
60<H2>Description</H2>
61<P>This function sets the Matrix mode to the Projection mode. This function also sets the Frustum matrix as the current matrix. If <em><strong><code>mtx</code></strong></em> is not <code>NULL</code>, then the perspective projection matrix is also set in *<em><strong><code>mtx</code></strong></em>.<BR>The diagram shows the matrix that is set.</P>
62<P><span lang=EN-US style='font-size:10.5pt;mso-bidi-font-size: 12.0pt;font-family:Century;mso-fareast-font-family:"MS ??";mso-bidi-font-family: "Times New Roman";mso-font-kerning:1.0pt;mso-ansi-language:EN-US;mso-fareast-language: JA;mso-bidi-language:AR-SA'><span style='mso-text-raise:-61.0pt'><IMG width="296" height="171" src="geo_perspective.gif" v:shapes="_x0000_i1025"></span></span></P>
63<P>The divider is used internally. Refer to <A href="../../cp/div/about_div.html#use_in_intr">Divider Usage Notes</A> when using this function inside an interrupt.</P>
64
65<h2>See Also</h2>
66<P><a href="G3_PerspectiveW.html"><code>G3_PerspectiveW</code></a>, <A href="G3_Frustum.html"><code>G3_Frustum</code></A>, <A href="G3_Ortho.html"><code>G3_Ortho</code></A></P>
67<H2>Revision History</H2>
68<P>2004/01/19 Initial version.</P>
69<hr><p>CONFIDENTIAL</p></body>
70</html>
71