From 5918e79f1e2930df61d8b9ffd5ad607156cae3e5 Mon Sep 17 00:00:00 2001 From: Hans-Christoph Steiner Date: Tue, 1 Apr 2003 05:54:43 +0000 Subject: renamed Olaf's maxlib/scale.c to range.c to get around name conflict with GEM svn path=/trunk/externals/hcs/; revision=522 --- range.c | 128 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 range.c (limited to 'range.c') diff --git a/range.c b/range.c new file mode 100644 index 0000000..106cd62 --- /dev/null +++ b/range.c @@ -0,0 +1,128 @@ +/* ------------------------- range ------------------------------------------ */ +/* */ +/* Ranges input to lie within an output range. */ +/* Written by Olaf Matthes */ +/* Get source at http://www.akustische-kunst.org/puredata/maxlib/ */ +/* */ +/* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +/* */ +/* Based on PureData by Miller Puckette and others. */ +/* */ +/* ---------------------------------------------------------------------------- */ + +#include "m_pd.h" +#include +#include + +static char *version = "range v0.2, written by Olaf Matthes "; + +typedef struct range +{ + t_object x_ob; + t_float x_f; /* current input value */ + t_float x_il; /* low border of input range */ + t_float x_ih; /* high border of input range */ + t_float x_ol; /* low border of output range */ + t_float x_oh; /* high border of output range */ + t_float x_logcoeff; /* log-coefficient */ + t_outlet *x_outlet1; /* result */ +} t_range; + +static void range_float(t_range *x, t_floatarg f) +{ + t_float ir = x->x_ih - x->x_il; + t_float or = x->x_oh - x->x_ol; + double oq; + double result; + double k; + if(ir == 0) + { + post("range: input range must not be 0"); + return; + } + /* we accept an output range of 0 in case someone really wants this */ + if(!x->x_logcoeff) /* linear */ + { + k = (or / ir); + result = ((f - x->x_il) * k) + x->x_ol; + } + else /* logarythmical range */ + { + oq = x->x_oh / x->x_ol; + // k = (log((double)oq)/log(x->x_logcoeff))/((double)ir); + k = log((double)oq)/((double)ir); + + if(x->x_ol) + { + // result = (double)x->x_ol*exp(k*(double)(f - x->x_il)*log(x->x_logcoeff)); + result = (double)x->x_ol*exp(k*(double)(f - x->x_il)); + } + else + { + /* in case the low output is 0 we have to cheat... */ + /* okay, here's the chating: we calculate for a lower out limit + of 1 and remove this shift after the calculation */ + result = ((double)(x->x_ol+1)*exp(k*(double)(f - x->x_il)))-1.0; + } + } + + x->x_f = f; /* save current input value */ + + outlet_float(x->x_outlet1, result); +} + +static void range_bang(t_range *x) +{ + range_float(x, x->x_f); /* recalculate result */ +} + +static t_class *range_class; + +static void *range_new(t_floatarg fil, t_floatarg fih, t_floatarg fol, t_floatarg foh, t_floatarg flc) +{ + t_range *x = (t_range *)pd_new(range_class); + + floatinlet_new(&x->x_ob, &x->x_il); + floatinlet_new(&x->x_ob, &x->x_ih); + floatinlet_new(&x->x_ob, &x->x_ol); + floatinlet_new(&x->x_ob, &x->x_oh); + floatinlet_new(&x->x_ob, &x->x_logcoeff); + + x->x_outlet1 = outlet_new(&x->x_ob, gensym("float")); + + /* default values taken from Max's range */ + x->x_il = fil; + x->x_ih = fih; + if(!x->x_ih)x->x_ih = 127.0; + x->x_ol = fol; + x->x_oh = foh; + if(!x->x_oh)x->x_oh = 1.0; + x->x_logcoeff = flc; + x->x_f = 0; + + post(version); + + return (void *)x; +} + +void range_setup(void) +{ + range_class = class_new(gensym("range"), (t_newmethod)range_new, + 0, sizeof(t_range), 0, A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, A_DEFFLOAT, 0); + class_addfloat(range_class, range_float); + class_addbang(range_class, range_bang); + class_sethelpsymbol(range_class, gensym("range.pd")); +} + -- cgit v1.2.1