Help/UGens/Random/RandSeed.html

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  30 <p class="p1"><span class="s1"><b>RandSeed<span class="Apple-tab-span"> </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span></b></span><b>set the synth's random generator seed</b></p>
  31 <p class="p2"><br></p>
  32 <p class="p1"><b>RandSeed.kr(trig, seed)</b></p>
  33 <p class="p1"><b>RandSeed.ar(trig, seed)</b></p>
  34 <p class="p3"><br></p>
  35 <p class="p1">When the trigger signal changes from nonpositive to positve, the synth's random generator <b>seed</b> is reset to the given value. All synths that use the same random number generator reproduce the same sequence of numbers again. The seed may be a demand rate ugen.</p>
  36 <p class="p3"><br></p>
  37 <p class="p1">see <a href="RandID.html"><span class="s2">RandID</span></a> ugen for setting the randgen id,<span class="Apple-converted-space"> </span></p>
  38 <p class="p1">also <a href="../../Core/Kernel/randomSeed.html"><span class="s2">randomSeed</span></a> for the client side equivalent</p>
  39 <p class="p3"><br></p>
  40 <p class="p1"><b>Note: </b>An audio rate version is not available, because other ugens look up random seeds<span class="Apple-converted-space">  </span>at control rate only.</p>
  41 <p class="p4"><br></p>
  42 <p class="p4"><br></p>
  43 <p class="p5"><br></p>
  44 <p class="p6">{ <span class="s3">RandSeed</span>.ar(<span class="s3">Impulse</span>.ar(3 ** <span class="s3">MouseX</span>.kr(1, 8)), 1871); <span class="s3">WhiteNoise</span>.ar * 0.1 }.play</p>
  45 <p class="p7"><br></p>
  46 <p class="p7"><br></p>
  47 <p class="p6">{ <span class="s3">RandSeed</span>.ar(<span class="s3">Impulse</span>.ar(3 ** <span class="s3">MouseX</span>.kr(1, 8)), <span class="s3">Dstutter</span>(<span class="s3">Dwhite</span>().exprange(2, 400), <span class="s3">Dwhite</span>().range(0, 1000))); <span class="s3">WhiteNoise</span>.ar * 0.1 }.play</p>
  48 <p class="p4"><br></p>
  49 <p class="p4"><br></p>
  50 <p class="p8">// start a noise patch</p>
  51 <p class="p9"><br></p>
  52 <p class="p10">(</p>
  53 <p class="p10">{</p>
  54 <p class="p10"><span class="s2">var</span> noise, filterfreq;</p>
  55 <p class="p10">noise = <span class="s2">WhiteNoise</span>.ar(0.05 ! 2) + <span class="s2">Dust2</span>.ar(70 ! 2);</p>
  56 <p class="p10">filterfreq = <span class="s2">LFNoise1</span>.kr(3, 5500, 6000);</p>
  57 <p class="p10"><span class="s2">Resonz</span>.ar(noise * 5, filterfreq, 0.5) + (noise * 0.5) <span class="Apple-converted-space"> </span></p>
  58 <p class="p10">}.play;</p>
  59 <p class="p10">)</p>
  60 <p class="p4"><br></p>
  61 <p class="p8">// reset the seed at a variable rate</p>
  62 <p class="p10">(</p>
  63 <p class="p10">x = { <span class="s2">arg</span> seed=1956;</p>
  64 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s2">RandSeed</span>.kr(<span class="s2">Impulse</span>.kr(<span class="s2">MouseX.kr(</span>0.1, 100)), seed);</p>
  65 <p class="p10">}.play;</p>
  66 <p class="p10">)<span class="Apple-tab-span">   </span></p>
  67 <p class="p9"><br></p>
  68 <p class="p9"><br></p>
  69 <p class="p9"><br></p>
  70 <p class="p10">x.set(<span class="s4">\seed</span>, 2001);</p>
  71 <p class="p10">x.set(<span class="s4">\seed</span>, 1798);</p>
  72 <p class="p10">x.set(<span class="s4">\seed</span>, 1902);</p>
  73 <p class="p9"><br></p>
  74 <p class="p9"><br></p>
  75 <p class="p8">// above you can see that the sound of the LFNoise1 is not exactly reproduced (filter frequency)</p>
  76 <p class="p8">// this is due to interference between the internal phase of the noise ugen and the<span class="Apple-converted-space"> </span></p>
  77 <p class="p8">// seed setting rate.</p>
  78 <p class="p9"><br></p>
  79 <p class="p8">// a solution is to start a new synth:</p>
  80 <p class="p9"><br></p>
  81 <p class="p10">(</p>
  82 <p class="p10"><span class="s2">SynthDef</span>(<span class="s4">\pseudorandom</span>, { <span class="s2">arg</span> out, sustain=1, seed=1967, id=0;</p>
  83 <p class="p10"><span class="Apple-tab-span">    </span><span class="s2">var</span> noise, filterfreq;</p>
  84 <p class="p10"><span class="Apple-tab-span">    </span><span class="s2">RandID</span>.ir(id);</p>
  85 <p class="p10"><span class="Apple-tab-span">    </span><span class="s2">RandSeed</span>.ir(1, seed);</p>
  86 <p class="p9"><span class="Apple-tab-span">     </span></p>
  87 <p class="p9"><span class="Apple-tab-span">     </span></p>
  88 <p class="p10"><span class="Apple-tab-span">    </span>noise = <span class="s2">WhiteNoise</span>.ar(0.05 ! 2) + <span class="s2">Dust2</span>.ar(70 ! 2);</p>
  89 <p class="p10"><span class="Apple-tab-span">    </span>filterfreq = <span class="s2">LFNoise1</span>.kr(3, 5500, 6000);</p>
  90 <p class="p9"><span class="Apple-tab-span">     </span></p>
  91 <p class="p10"><span class="Apple-tab-span">    </span><span class="s2">Out</span>.ar(out,</p>
  92 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s2">Resonz</span>.ar(noise * 5, filterfreq, 0.5) + (noise * 0.5)<span class="Apple-converted-space"> </span></p>
  93 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>*</p>
  94 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s2">Line</span>.kr(1, 0, sustain, doneAction:2)</p>
  95 <p class="p10"><span class="Apple-tab-span">    </span>)</p>
  96 <p class="p9"><br></p>
  97 <p class="p10">}).send(s);</p>
  98 <p class="p10">)</p>
  99 <p class="p9"><br></p>
 100 <p class="p8">// the exact same sound is reproduced</p>
 101 <p class="p10">(</p>
 102 <p class="p10">fork {</p>
 103 <p class="p10"><span class="Apple-tab-span">    </span>loop {</p>
 104 <p class="p11"><span class="s5"><span class="Apple-tab-span">   </span><span class="Apple-tab-span">    </span></span><span class="s2">Synth</span><span class="s5">(</span>\pseudorandom<span class="s5">);</span></p>
 105 <p class="p8"><span class="s5"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>1.1.wait; </span>// wait a bit longer than sustain, so sounds don't overlap</p>
 106 <p class="p10"><span class="Apple-tab-span">    </span>}</p>
 107 <p class="p10">}</p>
 108 <p class="p10">)</p>
 109 <p class="p9"><br></p>
 110 <p class="p8">// changing the rand seed changes the sound:</p>
 111 <p class="p9"><br></p>
 112 <p class="p10">(</p>
 113 <p class="p10">fork {</p>
 114 <p class="p10"><span class="Apple-tab-span">    </span>(1902..2005).do { <span class="s2">|seed|</span></p>
 115 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>seed.postln;</p>
 116 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>3.do {</p>
 117 <p class="p11"><span class="s5"><span class="Apple-tab-span">   </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span></span><span class="s2">Synth</span><span class="s5">(</span>\pseudorandom<span class="s5">, [</span>\seed<span class="s5">, seed]);</span></p>
 118 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>1.1.wait;</p>
 119 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>}</p>
 120 <p class="p10"><span class="Apple-tab-span">    </span>}</p>
 121 <p class="p10">}</p>
 122 <p class="p10">)</p>
 123 <p class="p9"><br></p>
 124 <p class="p8">// cd skipper</p>
 125 <p class="p10">(</p>
 126 <p class="p10">fork {</p>
 127 <p class="p10"><span class="Apple-tab-span">    </span>(1902..2005).do { <span class="s2">|seed|</span></p>
 128 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>seed.postln;</p>
 129 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>rrand(4,10).do {</p>
 130 <p class="p11"><span class="s5"><span class="Apple-tab-span">   </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span></span><span class="s2">Synth</span><span class="s5">(</span>\pseudorandom<span class="s5">, [</span>\seed<span class="s5">, seed, </span>\sustain<span class="s5">, 0.05]);</span></p>
 131 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0.06.wait;</p>
 132 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>}</p>
 133 <p class="p10"><span class="Apple-tab-span">    </span>}</p>
 134 <p class="p10">}</p>
 135 <p class="p10">)</p>
 136 <p class="p9"><br></p>
 137 <p class="p8">// if the sounds overlap, this does not work as expected anymore</p>
 138 <p class="p8">// sounds vary.</p>
 139 <p class="p9"><br></p>
 140 <p class="p10">(</p>
 141 <p class="p10">fork {</p>
 142 <p class="p10"><span class="Apple-tab-span">    </span>loop {</p>
 143 <p class="p11"><span class="s5"><span class="Apple-tab-span">   </span><span class="Apple-tab-span">    </span></span><span class="s2">Synth</span><span class="s5">(</span>\pseudorandom<span class="s5">);</span></p>
 144 <p class="p8"><span class="s5"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0.8.wait; </span>// instead of 1.1</p>
 145 <p class="p10"><span class="Apple-tab-span">    </span>}</p>
 146 <p class="p10">}</p>
 147 <p class="p10">)</p>
 148 <p class="p9"><br></p>
 149 <p class="p8">// rand id can be used to restrict the resetting of the seed to each voice:</p>
 150 <p class="p9"><br></p>
 151 <p class="p10">(</p>
 152 <p class="p10">fork {</p>
 153 <p class="p10"><span class="Apple-tab-span">    </span><span class="s2">var</span> id=0;</p>
 154 <p class="p10"><span class="Apple-tab-span">    </span>(1902..2005).do { <span class="s2">|seed|</span></p>
 155 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>seed.postln;</p>
 156 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>3.do {</p>
 157 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="s2">Synth</span>(<span class="s4">\pseudorandom</span>, [<span class="s4">\seed</span>, seed, <span class="s4">\id</span>, id]);</p>
 158 <p class="p8"><span class="s5"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>id = id + 1 % 16; </span>// there is 16 different random generators</p>
 159 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>0.8.wait;</p>
 160 <p class="p10"><span class="Apple-tab-span">    </span><span class="Apple-tab-span">    </span>}</p>
 161 <p class="p10"><span class="Apple-tab-span">    </span>}</p>
 162 <p class="p10">}</p>
 163 <p class="p10">)</p>
 164 <p class="p9"><br></p>
 165 <p class="p9"><br></p>
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