Looking for the original source code of SC oscillators

Hobbes · January 5, 2022, 10:44pm

Hello, in order to understand how a digital oscillator is build I would like to find the most primitive instance of code for - as an example - the SinOsc or Formant UGens. I tried to find thoses by checking the ressources inside the SC app but didn’t find it.
Also, when I try to open “source : Osc.sc” from the help menu I get an error message. ( “cannot open file : private…”).
Thanks !

jordan · January 5, 2022, 11:54pm

github.com

supercollider/supercollider/blob/develop/server/plugins/OscUGens.cpp

/*
    SuperCollider real time audio synthesis system
    Copyright (c) 2002 James McCartney. All rights reserved.
    http://www.audiosynth.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
*/

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It’s in c++ and there are bunch of nasty macros. All audio is ultimately c++ that is invoked from sclang, therefore you shall not find the DSP code there. In fact you’d be better off looking at DSP text books if you want to learn from fundementals.

Fyi, the SinOsc ugen uses a lookup table, meaning it storages the result of the sine wave in a buffer and uses a phase offset to read it back.

Hobbes · January 6, 2022, 2:12pm

Great, thanks a lot.