<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>loopxseg</title> <link rel="stylesheet" type="text/css" href="csound.css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.76.1" /> <link rel="home" href="index.html" title="The Canonical Csound Reference Manual" /> <link rel="up" href="OpcodesTop.html" title="Orchestra Opcodes and Operators" /> <link rel="prev" href="looptseg.html" title="looptseg" /> <link rel="next" href="lorenz.html" title="lorenz" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">loopxseg</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="looptseg.html">Prev</a> </td> <th width="60%" align="center">Orchestra Opcodes and Operators</th> <td width="20%" align="right"> <a accesskey="n" href="lorenz.html">Next</a></td> </tr> </table> <hr /> </div> <div class="refentry" title="loopxseg"> <a id="loopxseg"></a> <div class="titlepage"></div> <a id="IndexLoopxseg" class="indexterm"></a> <div class="refnamediv"> <h2> <span class="refentrytitle">loopxseg</span> </h2> <p>loopxseg — Generate control signal consisting of exponential segments delimited by two or more specified points. </p> </div> <div class="refsect1" title="Description"> <a id="idp29060848"></a> <h2>Description</h2> <p> Generate control signal consisting of exponential segments delimited by two or more specified points. The entire envelope is looped at <span class="emphasis"><em>kfreq</em></span> rate. Each parameter can be varied at k-rate. </p> </div> <div class="refsect1" title="Syntax"> <a id="idp29071264"></a> <h2>Syntax</h2> <pre class="synopsis">ksig <span class="command"><strong>loopxseg</strong></span> kfreq, ktrig, iphase, ktime0, kvalue0 [, ktime1] [, kvalue1] \ [, ktime2] [, kvalue2] [...]</pre> </div> <div class="refsect1" title="Performance"> <a id="idp29072384"></a> <h2>Performance</h2> <p> <span class="emphasis"><em>ksig</em></span> -- Output signal. </p> <p> <span class="emphasis"><em>kfreq</em></span> -- Repeat rate in Hz or fraction of Hz. </p> <p> <span class="emphasis"><em>ktrig</em></span> -- If non-zero, retriggers the envelope from start (see <a class="link" href="trigger.html" title="trigger"><em class="citetitle">trigger opcode</em></a>), before the envelope cycle is completed. </p> <p> <span class="emphasis"><em>iphase</em></span> -- A value between 0 and 1 to say where to start the loop. Zero, the commonest value, indicates the beginning. </p> <p> <span class="emphasis"><em>ktime0...ktimeN</em></span> -- Times of points; expressed in fraction of a cycle. </p> <p> <span class="emphasis"><em>kvalue0...kvalueN</em></span> -- Values of points </p> <p> <span class="emphasis"><em>loopxseg</em></span> opcode is similar to <a class="link" href="expseg.html" title="expseg"><em class="citetitle">expseg</em></a>, but the entire envelope is looped at <span class="emphasis"><em>kfreq</em></span> rate. Notice that times are not expressed in seconds but in fraction of a cycle. Actually each duration represent is proportional to the other, and the entire cycle duration is proportional to the sum of all duration values. </p> <p> The sum of all duration is then rescaled according to <span class="emphasis"><em>kfreq</em></span> argument. For example, considering an envelope made up of 3 segments, each segment having 100 as duration value, their sum will be 300. This value represents the total duration of the envelope, and is actually divided into 3 equal parts, a part for each segment. </p> <p> Actually, the real envelope duration in seconds is determined by <span class="emphasis"><em>kfreq</em></span>. Again, if the envelope is made up of 3 segments, but this time the first and last segments have a duration of 50, whereas the central segment has a duration of 100 again, their sum will be 200. This time 200 represent the total duration of the 3 segments, so the central segment will be twice as long as the other segments. </p> <p> All parameters can be varied at k-rate. Negative frequency values are allowed, reading the envelope backward. <span class="emphasis"><em>ktime0</em></span> should always be set to 0, except if the user wants some special effect. </p> </div> <div class="refsect1" title="Examples"> <a id="idp29143936"></a> <h2>Examples</h2> <p> Here is an example of the loopxseg opcode. It uses the file <a class="ulink" href="examples/loopxseg.csd" target="_top"><em class="citetitle">loopxseg.csd</em></a>. </p> <div class="example"> <a id="idp29144920"></a> <p class="title"> <strong>Example 408. Example of the loopxseg opcode.</strong> </p> <div class="example-contents"> <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p> <pre class="programlisting"> <span class="csdtag"><CsoundSynthesizer></span> <span class="csdtag"><CsOptions></span> <span class="comment">; Select audio/midi flags here according to platform</span> <span class="comment">; Audio out Audio in No messages</span> -odac -iadc -d <span class="comment">;;;RT audio I/O</span> <span class="comment">; For Non-realtime ouput leave only the line below:</span> <span class="comment">; -o loopxseg.wav -W ;;; for file output any platform</span> <span class="csdtag"></CsOptions></span> <span class="csdtag"><CsInstruments></span> <span class="comment">; Initialize the global variables.</span> <span class="ohdr">sr</span> <span class="op">=</span> 44100 <span class="ohdr">kr</span> <span class="op">=</span> 4410 <span class="ohdr">ksmps</span> <span class="op">=</span> 10 <span class="ohdr">nchnls</span> <span class="op">=</span> 2 <span class="ohdr">0dbfs</span> <span class="op">=</span> 1 <span class="comment">; Instrument #1</span> <span class="oblock">instr</span> 1 kfreq <span class="opc">line</span> 1, p3, 20 kval <span class="op">=</span> p4 <span class="comment">; value of second segment</span> klp loopxseg kfreq, 0, 0, 0, 0, kval, 1, 1, 0 a1 <span class="opc">poscil3</span> klp, 440, 1 <span class="opc">out</span> a1,a1 <span class="oblock">endin</span> <span class="csdtag"></CsInstruments></span> <span class="csdtag"><CsScore></span> <span class="comment">; Table #1, a sine wave.</span> <span class="stamnt">f</span> 1 0 16384 10 1 <span class="comment">; Play Instrument #1 for five seconds.</span> <span class="stamnt">i</span> 1 0 5 .05 <span class="stamnt">i</span> 1 6 5 .5 <span class="stamnt">e</span> <span class="csdtag"></CsScore></span> <span class="csdtag"></CsoundSynthesizer></span> </pre> </div> </div> <p><br class="example-break" /> </p> </div> <div class="refsect1" title="See Also"> <a id="idp29147200"></a> <h2>See Also</h2> <p> <a class="link" href="lpshold.html" title="lpshold"><em class="citetitle">lpshold</em></a> <a class="link" href="loopseg.html" title="loopseg"><em class="citetitle">loopseg</em></a> </p> </div> <div class="refsect1" title="Credits"> <a id="idp29148680"></a> <h2>Credits</h2> <p>Author: John ffitch</p> <p>New in Version 5.12</p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="looptseg.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="OpcodesTop.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="lorenz.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">looptseg </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> lorenz</td> </tr> </table> </div> </body> </html>