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<div id='toctitle'>Sweep:</div>
<span class='toc_search'>Filter: <input id='toc_search'></span><ul class='toc'><li class='toc1'><a href='#description'>Description</a></li>
<ul class='toc'></ul><li class='toc1'><a href='#classmethods'>Class methods</a></li>
<ul class='toc'><li class='toc3'><a href='#*ar'>ar</a> <a href='#*kr'>kr</a> </li>
<li class='toc2'><a href='#Inherited%20class%20methods'>Inherited class methods</a></li>
</ul><li class='toc1'><a href='#instancemethods'>Instance methods</a></li>
<ul class='toc'><li class='toc2'><a href='#Inherited%20instance%20methods'>Inherited instance methods</a></li>
</ul><li class='toc1'><a href='#examples'>Examples</a></li>
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<span id='folder'>Classes</span>
| <span id='categories'><a href='./../Browse.html#UGens'>UGens</a> > <a href='./../Browse.html#UGens>Triggers'>Triggers</a></span>
</div><h1>Sweep<span id='superclasses'> : <a href="../Classes/UGen.html">UGen</a> : <a href="../Classes/AbstractFunction.html">AbstractFunction</a> : <a href="../Classes/Object.html">Object</a></span>
</h1>
<div id='summary'>Triggered linear ramp</div>
</div>
<div class='subheader'>
<div id='filename'>Source: <a href='file:///Applications/SuperCollider.app/Contents/Resources/SCClassLibrary/Common/Audio/Trig.sc' title='/Applications/SuperCollider.app/Contents/Resources/SCClassLibrary/Common/Audio/Trig.sc'>Trig.sc</a></div></div>
<h2><a class='anchor' name='description'>Description</a></h2>
<p>Starts a linear raise by rate/sec from zero when trig input crosses from non-positive to positive.
<p>When rate == 1, Sweep may be used to get a continually-updating measurement of the time (in seconds) since the last trigger.<h2><a class='anchor' name='classmethods'>Class Methods</a></h2>
<h3 class='method-code'><span class='method-prefix'>Sweep.</span><a class='method-name' name='*ar' href='./../Overviews/Methods.html#ar'>ar</a>(<span class='argstr'>trig: 0</span>, <span class='argstr'>rate: 1</span>)</h3>
<h3 class='method-code'><span class='method-prefix'>Sweep.</span><a class='method-name' name='*kr' href='./../Overviews/Methods.html#kr'>kr</a>(<span class='argstr'>trig: 0</span>, <span class='argstr'>rate: 1</span>)</h3>
<div class='method'>
<p><h4>Arguments:</h4>
<table class='arguments'>
<tr><td class='argumentname'>trig<td class='argumentdesc'>
<p>triggers when trig input crosses from non-positive to positive.<tr><td class='argumentname'>rate<td class='argumentdesc'>
<p>rate/sec raise rate</table></div><h3><a class='anchor' name='Inherited%20class%20methods'>Inherited class methods</a></h3>
<div id='inheritedclassmets'></div><h2><a class='anchor' name='instancemethods'>Instance Methods</a></h2>
<h3><a class='anchor' name='Inherited%20instance%20methods'>Inherited instance methods</a></h3>
<div id='inheritedinstmets'></div><h2><a class='anchor' name='examples'>Examples</a></h2>
<pre class='code prettyprint lang-sc'>// using sweep to modulate sine frequency
(
{ var trig;
trig = Impulse.kr(MouseX.kr(0.5, 20, 1));
SinOsc.ar(Sweep.kr(trig, 700) + 500, 0, 0.2)
}.play;
)
// using sweep to index into a buffer
b = Buffer.read(s, Platform.resourceDir +/+ "sounds/a11wlk01.wav");
(
{ var trig;
trig = Impulse.kr(MouseX.kr(0.5, 10, 1));
BufRd.ar(1, b, Sweep.ar(trig, BufSampleRate.ir(0)))
}.play;
)
// backwards, variable offset
(
{ var trig, pos, rate;
trig = Impulse.kr(MouseX.kr(0.5, 10, 1));
rate = BufSampleRate.ir(0);
pos = Sweep.ar(trig, rate.neg) + (BufFrames.ir(0) * LFNoise0.kr(0.2));
BufRd.ar(1, b, pos)
}.play;
)
// raising rate
(
{ var trig, rate;
trig = Impulse.kr(MouseX.kr(0.5, 10, 1));
rate = Sweep.kr(trig, 2) + 0.5;
BufRd.ar(1, b, Sweep.ar(trig, BufSampleRate.ir(0) * rate))
}.play;
)
b.free</pre>
<p>Sweep can be used as a resettable <a href="./../Classes/Phasor.html">Phasor</a> or <a href="./../Classes/Line.html">Line</a> - one that can start, pause, resume and stop. To get a resettable <a href="./../Classes/XLine.html">XLine</a> behavior change the <code class='code prettyprint lang-sc'>linlin</code> to <code class='code prettyprint lang-sc'>linexp</code> in the SynthDef below.<pre class='code prettyprint lang-sc'>(
SynthDef(\lineReset, { |out, start= 0, end= 1, dur= 1, t_trig= 1, run= 1|
var phasor = Sweep.ar(t_trig, run / dur).linlin(0, 1, start, end, \minmax);
phasor.poll;
Out.ar(out, SinOsc.ar(phasor, 0, 0.2));
}).add;
)
a = Synth(\lineReset, [\start, 400, \end, 800, \dur, 2])
a.set(\t_trig, 1)
a.set(\run, 0)
a.set(\run, 1)
a.set(\t_trig, 1)
a.free
//shorter duration and downwards...
a= Synth(\lineReset, [\start, 1000, \end, 500, \dur, 0.5])
a.set(\t_trig, 1)
a.set(\run, 0)
a.set(\run, 1)
a.set(\t_trig, 1)
a.free</pre>
<p><div class='doclink'>helpfile source: <a href='file:///Applications/SuperCollider.app/Contents/Resources/HelpSource/Classes/Sweep.schelp'>/Applications/SuperCollider.app/Contents/Resources/HelpSource/Classes/Sweep.schelp</a><br>link::Classes/Sweep::<br></div></div></body></html>