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8<TITLE>VECDotProduct</TITLE>
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11<H1>VECDotProduct</H1>
12
13<H2>Syntax</H2>
14<dl><dd><pre class="construction">
15#include &lt;revolution/mtx.h&gt;
16
17f32 C_VECDotProduct ( const Vec* a, const Vec* b );
18f32 PSVECDotProduct ( const Vec* a, const Vec* b );
19
20#define VECDotProduct&nbsp; C_VECDotProduct // for debug build
21#define VECDotProduct&nbsp; PSVECDotProduct // for nondebug build
22</pre></dd></dl>
23
24<H2>Arguments</H2>
25<TABLE class="arguments" border="1" >
26  <TBODY>
27    <TR>
28<TH>a</TH>
29<TD>Pointer to the first <A href="../structures/Vec_VecPtr.html"><CODE>Vec</CODE></A>.&nbsp;<SPAN class="argument">a</SPAN> is not altered by this function.</TD>
30    </TR>
31    <TR>
32<TH>b</TH>
33<TD>Pointer to the second <CODE><A href="../structures/Vec_VecPtr.html">Vec</A></CODE>.&nbsp;&nbsp;<SPAN class="argument">b</SPAN> is not altered by this function.</TD>
34    </TR>
35  </TBODY>
36</TABLE>
37
38<H2>Return Values</H2>
39<P>Returns the dot product of <SPAN class="argument">a</SPAN> and <SPAN class="argument">b</SPAN>.</P>
40
41<H2>Description</H2>
42<P>Finds the inner product of two vectors. <SPAN class="argument">a</SPAN> and <SPAN class="argument">b</SPAN> do not need to be unit vectors and are not normalized inside this function. To use <CODE>VECDotProduct</CODE> to calculate the cosine directly, <SPAN class="argument">a</SPAN> and <SPAN class="argument">b</SPAN> must be normalized before calling this routine.</P>
43<P>During a debug build, <code>VECDotProduct</code> is interpreted as <code>C_VECDotProduct</code>, which is a normal C language version. During a non-debug build for a Broadway processor, the paired-singles equivalent of this function, <code><font face="Courier New">PSVECDotProduct</font></code>, will be automatically substituted. You can also call each of <code>C_VECDotProduct/PSVECDotProduct</code> explicitly.</P>
44
45<H2>See Also</H2>
46<P class="reference">
47<A href="../structures/Vec_VecPtr.html">Vec, VecPtr</A>,
48<A href="VECCrossProduct.html">VECCrossProduct</A>
49</P>
50
51<H2>Revision History</H2>
52<P>
532006/03/01 Initial version.
54</P>
55
56<hr><p>CONFIDENTIAL</p></body>
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