diff options
Diffstat (limited to 'src/iemlib2/fade~.c')
| -rw-r--r-- | src/iemlib2/fade~.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/iemlib2/fade~.c b/src/iemlib2/fade~.c new file mode 100644 index 0000000..2cae70d --- /dev/null +++ b/src/iemlib2/fade~.c @@ -0,0 +1,176 @@ +/* For information on usage and redistribution, and for a DISCLAIMER OF ALL +* WARRANTIES, see the file, "LICENSE.txt," in this distribution. + +iemlib2 written by Thomas Musil, Copyright (c) IEM KUG Graz Austria 2000 - 2005 */ + +#include "m_pd.h" +#include "iemlib.h" +#include <math.h> + +/* ------------------------- fade~ ----------------------------- */ +/* --- signal lookup tabel object with input range of 0 to 1 --- */ +/* ---- converts a linear signal ramp to the half of a : ------ */ +/* -- sine-wave, hanning-wave, squareroot-wave or mixes of it -- */ + +t_float *iem_fade_tilde_table_lin=(t_float *)0L; +t_float *iem_fade_tilde_table_linsqrt=(t_float *)0L; +t_float *iem_fade_tilde_table_sqrt=(t_float *)0L; +t_float *iem_fade_tilde_table_sin=(t_float *)0L; +t_float *iem_fade_tilde_table_sinhann=(t_float *)0L; +t_float *iem_fade_tilde_table_hann=(t_float *)0L; + +static t_class *fade_tilde_class; + +typedef struct _fade +{ + t_object x_obj; + t_float *x_table; + t_float x_f; +} t_fade_tilde; + +static void fade_set(t_fade_tilde *x, t_symbol *s) +{ + if(s == gensym("_lin")) + x->x_table = iem_fade_tilde_table_lin; + else if(s == gensym("_linsqrt")) + x->x_table = iem_fade_tilde_table_linsqrt; + else if(s == gensym("_sqrt")) + x->x_table = iem_fade_tilde_table_sqrt; + else if(s == gensym("_sin")) + x->x_table = iem_fade_tilde_table_sin; + else if(s == gensym("_sinhann")) + x->x_table = iem_fade_tilde_table_sinhann; + else if(s == gensym("_hann")) + x->x_table = iem_fade_tilde_table_hann; +} + +static void *fade_new(t_symbol *s) +{ + t_fade_tilde *x = (t_fade_tilde *)pd_new(fade_tilde_class); + outlet_new(&x->x_obj, gensym("signal")); + x->x_f = 0; + x->x_table = iem_fade_tilde_table_lin; + fade_set(x, s); + return (x); +} + +static t_int *fade_perform(t_int *w) +{ + t_float *in = (t_float *)(w[1]); + t_float *out = (t_float *)(w[2]); + t_fade_tilde *x = (t_fade_tilde *)(w[3]); + int n = (int)(w[4]); + t_float *tab = x->x_table, *addr, f1, f2, frac; + double dphase; + int normhipart; + union tabfudge tf; + + tf.tf_d = UNITBIT32; + normhipart = tf.tf_i[HIOFFSET]; + +#if 0 /* this is the readable version of the code. */ + while (n--) + { + dphase = (double)(*in++ * (t_float)(COSTABSIZE) * 0.99999) + UNITBIT32; + tf.tf_d = dphase; + addr = tab + (tf.tf_i[HIOFFSET] & (COSTABSIZE-1)); + tf.tf_i[HIOFFSET] = normhipart; + frac = tf.tf_d - UNITBIT32; + f1 = addr[0]; + f2 = addr[1]; + *out++ = f1 + frac * (f2 - f1); + } +#endif +#if 1 /* this is the same, unwrapped by hand. */ + dphase = (double)(*in++ * (t_float)(COSTABSIZE) * 0.99999) + UNITBIT32; + tf.tf_d = dphase; + addr = tab + (tf.tf_i[HIOFFSET] & (COSTABSIZE-1)); + tf.tf_i[HIOFFSET] = normhipart; + while (--n) + { + dphase = (double)(*in++ * (t_float)(COSTABSIZE) * 0.99999) + UNITBIT32; + frac = tf.tf_d - UNITBIT32; + tf.tf_d = dphase; + f1 = addr[0]; + f2 = addr[1]; + addr = tab + (tf.tf_i[HIOFFSET] & (COSTABSIZE-1)); + *out++ = f1 + frac * (f2 - f1); + tf.tf_i[HIOFFSET] = normhipart; + } + frac = tf.tf_d - UNITBIT32; + f1 = addr[0]; + f2 = addr[1]; + *out++ = f1 + frac * (f2 - f1); +#endif + return (w+5); +} + +static void fade_dsp(t_fade_tilde *x, t_signal **sp) +{ + dsp_add(fade_perform, 4, sp[0]->s_vec, sp[1]->s_vec, x, sp[0]->s_n); +} + +static void fade_maketable(void) +{ + int i; + t_float *fp, phase, fff,phsinc = 0.5*3.141592653 / ((t_float)COSTABSIZE*0.99999); + union tabfudge tf; + + if(!iem_fade_tilde_table_sin) + { + iem_fade_tilde_table_sin = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_sin, phase=0; i--; fp++, phase+=phsinc) + *fp = sin(phase); + } + if(!iem_fade_tilde_table_sinhann) + { + iem_fade_tilde_table_sinhann = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_sinhann, phase=0; i--; fp++, phase+=phsinc) + { + fff = sin(phase); + *fp = fff*sqrt(fff); + } + } + if(!iem_fade_tilde_table_hann) + { + iem_fade_tilde_table_hann = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_hann, phase=0; i--; fp++, phase+=phsinc) + { + fff = sin(phase); + *fp = fff*fff; + } + } + phsinc = 1.0 / ((t_float)COSTABSIZE*0.99999); + if(!iem_fade_tilde_table_lin) + { + iem_fade_tilde_table_lin = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_lin, phase=0; i--; fp++, phase+=phsinc) + *fp = phase; + } + if(!iem_fade_tilde_table_linsqrt) + { + iem_fade_tilde_table_linsqrt = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_linsqrt, phase=0; i--; fp++, phase+=phsinc) + *fp = pow(phase, 0.75); + } + if(!iem_fade_tilde_table_sqrt) + { + iem_fade_tilde_table_sqrt = (t_float *)getbytes(sizeof(t_float) * (COSTABSIZE+1)); + for(i=COSTABSIZE+1, fp=iem_fade_tilde_table_sqrt, phase=0; i--; fp++, phase+=phsinc) + *fp = sqrt(phase); + } + tf.tf_d = UNITBIT32 + 0.5; + if((unsigned)tf.tf_i[LOWOFFSET] != 0x80000000) + bug("fade~: unexpected machine alignment"); +} + +void fade_tilde_setup(void) +{ + fade_tilde_class = class_new(gensym("fade~"), (t_newmethod)fade_new, 0, + sizeof(t_fade_tilde), 0, A_DEFSYM, 0); + CLASS_MAINSIGNALIN(fade_tilde_class, t_fade_tilde, x_f); + class_addmethod(fade_tilde_class, (t_method)fade_dsp, gensym("dsp"), 0); + class_addmethod(fade_tilde_class, (t_method)fade_set, gensym("set"), A_DEFSYM, 0); + class_sethelpsymbol(fade_tilde_class, gensym("iemhelp/help-fade~")); + fade_maketable(); +} |