diff options
| -rw-r--r-- | rcosc~/rcosc~-help.pd | 44 | ||||
| -rw-r--r-- | rcosc~/rcosc~.c | 117 |
2 files changed, 161 insertions, 0 deletions
diff --git a/rcosc~/rcosc~-help.pd b/rcosc~/rcosc~-help.pd new file mode 100644 index 0000000..7b7ca9d --- /dev/null +++ b/rcosc~/rcosc~-help.pd @@ -0,0 +1,44 @@ +#N canvas 710 282 450 439 10; +#X obj 53 277 *~; +#X text 181 301 Author: Martin Peach; +#X obj 54 316 dac~; +#X obj 68 228 nbx 5 14 0 1000 0 1 empty empty level 60 8 0 10 -4034 +-13381 -13381 8 256; +#X obj 68 253 / 1000; +#X obj 168 244 tabwrite~ \$0-rcoschelp; +#X obj 168 267 table \$0-rcoschelp; +#X obj 168 213 metro 100; +#X obj 168 194 tgl 15 0 empty empty graph 17 7 0 10 -4034 -13381 -1 +1 1; +#X obj 52 169 rcosc~ 0.001; +#X floatatom 52 28 5 0 0 0 - - -; +#X obj 52 135 / 1; +#X obj 52 70 t b f; +#X msg 52 103 0.722057; +#X text 155 68 7.22057e+07; +#X text 223 68 70756; +#X text 147 68 0; +#X obj 52 5 r note_a; +#X obj 52 49 mtof; +#X floatatom 92 66 5 0 0 0 - - -; +#X text 49 -57 rcosc~ emulates an oscillator implemented with a capacitor +charging through a resistor. The creation argument can be overriden +by the inlet \, and represents a charging time constant in seconds. +; +#X text 180 320 2010/04/15; +#X connect 0 0 2 0; +#X connect 0 0 2 1; +#X connect 3 0 4 0; +#X connect 4 0 0 1; +#X connect 7 0 5 0; +#X connect 8 0 7 0; +#X connect 9 0 5 0; +#X connect 9 0 0 0; +#X connect 10 0 18 0; +#X connect 11 0 9 0; +#X connect 12 0 13 0; +#X connect 12 1 11 1; +#X connect 13 0 11 0; +#X connect 17 0 10 0; +#X connect 18 0 12 0; +#X connect 18 0 19 0; diff --git a/rcosc~/rcosc~.c b/rcosc~/rcosc~.c new file mode 100644 index 0000000..0ab1c9d --- /dev/null +++ b/rcosc~/rcosc~.c @@ -0,0 +1,117 @@ +/* rcosc~.c by Martin Peach 20100331 */ +/* Pd external emulating a resistor-capacitor-controlled oscillator */ +/* The first control parameter is a time constant in seconds (or resistance X capacitance) */ +/* The second control parameter is a threshold above which the cap is set to discharge */ +/* The third control parameter is a threshold below which the cap is set to charge */ + +#include "m_pd.h" + +static t_class *rcosc_tilde_class; + +typedef struct _rcosc_tilde +{ + t_object rc_obj; + t_float rc_f; + t_float rc_upper_threshold; /* if rc_dir is 1, charge to here */ + t_float rc_lower_threshold; /* if rc_dir is 0, discharge to here */ + t_int rc_dir; + double rc_node; + double rc_one; + double rc_zero; + double rc_sp; + double rc_slewmax; +} t_rcosc_tilde; + +static t_int *rcosc_tilde_perform(t_int *w); +static void rcosc_tilde_dsp(t_rcosc_tilde *x, t_signal **sp); +static void *rcosc_tilde_new(t_floatarg f); + +static t_int *rcosc_tilde_perform(t_int *w) +{ + t_rcosc_tilde *x = (t_rcosc_tilde *)(w[1]); + t_sample *in = (t_sample *)(w[2]); + t_sample *out = (t_sample *)(w[3]); + int n = (int)(w[4]); + double slewrate, delta, node, overshoot; + int i, n_oversamples = 64; + +// if (x->rc_rc < x->rc_sp) slewrate = 1.0; +// else slewrate = x->rc_sp/x->rc_rc; + + while (n--) + { + slewrate = x->rc_one/(n_oversamples*(x->rc_sp*(*in++))); + if (slewrate < x->rc_zero) slewrate = x->rc_zero; + else if (slewrate > x->rc_one) slewrate = x->rc_one; + node = x->rc_node; + for (i = 0; i < n_oversamples; ++i) + { + if (x->rc_dir) + { + delta = slewrate*(x->rc_one - x->rc_node); + if (delta > x->rc_slewmax) delta = x->rc_slewmax; + x->rc_node += delta; + overshoot = x->rc_node - x->rc_upper_threshold; + if (overshoot > 0) + { + x->rc_dir = 0; + x->rc_node = x->rc_upper_threshold - overshoot; /* bounce */ + } + } + else + { + delta = slewrate*(x->rc_zero - x->rc_node); + if (delta < -x->rc_slewmax) delta = -x->rc_slewmax; + x->rc_node += delta; + overshoot = x->rc_lower_threshold - x->rc_node; + if (overshoot > 0) + { + x->rc_dir = 1; + x->rc_node = x->rc_lower_threshold + overshoot; /* bounce */ + } + } + } + *out++ = ((node + x->rc_node)*3)-3; + } + return (w+5); +} + +static void rcosc_tilde_dsp(t_rcosc_tilde *x, t_signal **sp) +{ + x->rc_sp = sys_getsr(); + dsp_add(rcosc_tilde_perform, 4, x, sp[0]->s_vec, sp[1]->s_vec, sp[0]->s_n); +} + +static void *rcosc_tilde_new(t_floatarg f) +{ + t_rcosc_tilde *x = (t_rcosc_tilde *)pd_new(rcosc_tilde_class); + + x->rc_f = f; + x->rc_node = 0.0; + x->rc_upper_threshold = 0.666; /* if rc_dir is 1, charge to here */ + x->rc_lower_threshold = 0.333; /* if rc_dir is 0, discharge to here */ + x->rc_slewmax = 0.003;/* arbitrary slew rate limit */ + x->rc_dir = 1; /* start charging */ + x->rc_one = 1; + x->rc_zero = 0; + + outlet_new(&x->rc_obj, &s_signal); + + post("rcosc~ 20100331 Martin Peach"); + return (void *)x; +} + +void rcosc_tilde_setup(void) +{ + rcosc_tilde_class = class_new(gensym("rcosc~"), + (t_newmethod)rcosc_tilde_new, + 0, sizeof(t_rcosc_tilde), + CLASS_DEFAULT, + A_DEFFLOAT, 0); + + class_addmethod(rcosc_tilde_class, (t_method)rcosc_tilde_dsp, gensym("dsp"), 0); + CLASS_MAINSIGNALIN(rcosc_tilde_class, t_rcosc_tilde, rc_f); +} + +/* fin rcosc~.c */ + |