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_PerspectiveW</title>
9<LINK rel="stylesheet" href="../../css/nitro.css" type="text/css">
10</head>
11
12<body>
13
14<h1 align="left">G3_PerspectiveW <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_PerspectiveW(
22    fx32 fovySin,
23    fx32 fovyCos,
24    fx32 aspect,
25    fx32 n,
26    fx32 f,
27    fx32 scaleW,
28    MtxFx44 * mtx
29);</CODE></PRE></dd>
30</dl><h2>Arguments</h2>
31<TABLE border="1" width="100%">
32  <TBODY>
33    <TR>
34      <TD width="190"><em><strong><font face="Courier New">fovySin</font></strong></em></TD>
35      <TD width="512">Sine value of (the field-of-view angle in y-direction)/2</TD>
36    </TR>
37    <TR>
38      <TD width="190"><em><strong><font face="Courier New">fovyCos</font></strong></em></TD>
39      <TD width="512">Cosine value of (the field-of-view angle in y-direction)/2</TD>
40    </TR>
41    <TR>
42      <TD><em><strong><font face="Courier New">aspect</font></strong></em></TD>
43      <TD>Ratio of width of view field to height of view field (aspect ratio: width/height of the field of view)</TD>
44    </TR>
45    <TR>
46      <TD><em><strong><font face="Courier New">n</font></strong></em></TD>
47      <TD>Distance from viewpoint to the near clipping plane</TD>
48    </TR>
49    <TR>
50      <TD><em><strong><font face="Courier New">f</font></strong></em></TD>
51      <TD>Distance from viewpoint to the far clipping plane</TD>
52    </TR>
53    <TR>
54      <TD><em><strong><font face="Courier New">scaleW</font></strong></em></TD>
55      <TD>Precision adjustment parameter for the view volume</TD>
56    </TR>
57    <TR>
58      <TD width="190"><em><strong><font face="Courier New">mtx</font></strong></em></TD>
59      <TD width="512">Pointer to a 4x4 matrix.</TD>
60    </TR>
61  </TBODY>
62</TABLE>
63<h2>Return Values</h2>
64<p>None.</p>
65<H2>Description</H2>
66<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>
67<P><IMG width="191" height="163" src="geo_frustum.gif" v:shapes="_x0000_i1025" align="middle"> &times; <I>scaleW</I></P>
68<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>
69
70<h2>See Also</h2>
71<P><A href="G3_Perspective.html"><code>G3_Perspectve</code></A>, <A href="G3_FrustumW.html"><code>G3_FrustumW</code></A>, <A href="G3_OrthoW.html"><code>G3_OrthoW</code></A></P>
72<H2>Revision History</H2>
73<P>2004/04/27 Initial version.</P>
74<hr><p>CONFIDENTIAL</p></body>
75</html>
76