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path: root/apps/plugins/pdbox/PDa/intern/biquad~.c
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Diffstat (limited to 'apps/plugins/pdbox/PDa/intern/biquad~.c')
-rw-r--r--apps/plugins/pdbox/PDa/intern/biquad~.c252
1 files changed, 252 insertions, 0 deletions
diff --git a/apps/plugins/pdbox/PDa/intern/biquad~.c b/apps/plugins/pdbox/PDa/intern/biquad~.c
new file mode 100644
index 0000000000..c37182a911
--- /dev/null
+++ b/apps/plugins/pdbox/PDa/intern/biquad~.c
@@ -0,0 +1,252 @@
1#include <m_pd.h>
2#include <m_fixed.h>
3
4typedef struct biquadctl
5{
6 t_sample c_x1;
7 t_sample c_x2;
8 t_sample c_fb1;
9 t_sample c_fb2;
10 t_sample c_ff1;
11 t_sample c_ff2;
12 t_sample c_ff3;
13} t_biquadctl;
14
15typedef struct sigbiquad
16{
17 t_object x_obj;
18 float x_f;
19 t_biquadctl x_cspace;
20 t_biquadctl *x_ctl;
21} t_sigbiquad;
22
23t_class *sigbiquad_class;
24
25static void sigbiquad_list(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv);
26
27static void *sigbiquad_new(t_symbol *s, int argc, t_atom *argv)
28{
29 t_sigbiquad *x = (t_sigbiquad *)pd_new(sigbiquad_class);
30 outlet_new(&x->x_obj, gensym("signal"));
31 x->x_ctl = &x->x_cspace;
32 x->x_cspace.c_x1 = x->x_cspace.c_x2 = 0;
33 sigbiquad_list(x, s, argc, argv);
34 x->x_f = 0;
35 return (x);
36}
37
38static t_int *sigbiquad_perform(t_int *w)
39{
40 t_sample *in = (t_sample *)(w[1]);
41 t_sample *out = (t_sample *)(w[2]);
42 t_biquadctl *c = (t_biquadctl *)(w[3]);
43 int n = (t_int)(w[4]);
44 int i;
45 t_sample last = c->c_x1;
46 t_sample prev = c->c_x2;
47 t_sample fb1 = c->c_fb1;
48 t_sample fb2 = c->c_fb2;
49 t_sample ff1 = c->c_ff1;
50 t_sample ff2 = c->c_ff2;
51 t_sample ff3 = c->c_ff3;
52 for (i = 0; i < n; i++)
53 {
54 t_sample output = *in++ + mult(fb1,last) + mult(fb2,prev);
55 if (PD_BADFLOAT(output))
56 output = 0;
57 *out++ = mult(ff1,output) + mult(ff2,last) + mult(ff3,prev);
58 prev = last;
59 last = output;
60 }
61 c->c_x1 = last;
62 c->c_x2 = prev;
63 return (w+5);
64}
65
66static void sigbiquad_list(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv)
67{
68 float fb1 = atom_getfloatarg(0, argc, argv);
69 float fb2 = atom_getfloatarg(1, argc, argv);
70 float ff1 = atom_getfloatarg(2, argc, argv);
71 float ff2 = atom_getfloatarg(3, argc, argv);
72 float ff3 = atom_getfloatarg(4, argc, argv);
73 float discriminant = fb1 * fb1 + 4 * fb2;
74 t_biquadctl *c = x->x_ctl;
75 if (discriminant < 0) /* imaginary roots -- resonant filter */
76 {
77 /* they're conjugates so we just check that the product
78 is less than one */
79 if (fb2 >= -1.0f) goto stable;
80 }
81 else /* real roots */
82 {
83 /* check that the parabola 1 - fb1 x - fb2 x^2 has a
84 vertex between -1 and 1, and that it's nonnegative
85 at both ends, which implies both roots are in [1-,1]. */
86 if (fb1 <= 2.0f && fb1 >= -2.0f &&
87 1.0f - fb1 -fb2 >= 0 && 1.0f + fb1 - fb2 >= 0)
88 goto stable;
89 }
90 /* if unstable, just bash to zero */
91 fb1 = fb2 = ff1 = ff2 = ff3 = 0;
92stable:
93 c->c_fb1 = ftofix(fb1);
94 c->c_fb2 = ftofix(fb2);
95 c->c_ff1 = ftofix(ff1);
96 c->c_ff2 = ftofix(ff2);
97 c->c_ff3 = ftofix(ff3);
98}
99
100static void sigbiquad_set(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv)
101{
102 t_biquadctl *c = x->x_ctl;
103 c->c_x1 = atom_getfloatarg(0, argc, argv);
104 c->c_x2 = atom_getfloatarg(1, argc, argv);
105}
106
107static void sigbiquad_dsp(t_sigbiquad *x, t_signal **sp)
108{
109 dsp_add(sigbiquad_perform, 4,
110 sp[0]->s_vec, sp[1]->s_vec,
111 x->x_ctl, sp[0]->s_n);
112
113}
114
115void biquad_tilde_setup(void)
116{
117 sigbiquad_class = class_new(gensym("biquad~"), (t_newmethod)sigbiquad_new,
118 0, sizeof(t_sigbiquad), 0, A_GIMME, 0);
119 CLASS_MAINSIGNALIN(sigbiquad_class, t_sigbiquad, x_f);
120 class_addmethod(sigbiquad_class, (t_method)sigbiquad_dsp, gensym("dsp"), 0);
121 class_addlist(sigbiquad_class, sigbiquad_list);
122 class_addmethod(sigbiquad_class, (t_method)sigbiquad_set, gensym("set"),
123 A_GIMME, 0);
124 class_addmethod(sigbiquad_class, (t_method)sigbiquad_set, gensym("clear"),
125 A_GIMME, 0);
126}
127#include <m_pd.h>
128#include <m_fixed.h>
129
130typedef struct biquadctl
131{
132 t_sample c_x1;
133 t_sample c_x2;
134 t_sample c_fb1;
135 t_sample c_fb2;
136 t_sample c_ff1;
137 t_sample c_ff2;
138 t_sample c_ff3;
139} t_biquadctl;
140
141typedef struct sigbiquad
142{
143 t_object x_obj;
144 float x_f;
145 t_biquadctl x_cspace;
146 t_biquadctl *x_ctl;
147} t_sigbiquad;
148
149t_class *sigbiquad_class;
150
151static void sigbiquad_list(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv);
152
153static void *sigbiquad_new(t_symbol *s, int argc, t_atom *argv)
154{
155 t_sigbiquad *x = (t_sigbiquad *)pd_new(sigbiquad_class);
156 outlet_new(&x->x_obj, gensym("signal"));
157 x->x_ctl = &x->x_cspace;
158 x->x_cspace.c_x1 = x->x_cspace.c_x2 = 0;
159 sigbiquad_list(x, s, argc, argv);
160 x->x_f = 0;
161 return (x);
162}
163
164static t_int *sigbiquad_perform(t_int *w)
165{
166 t_sample *in = (t_sample *)(w[1]);
167 t_sample *out = (t_sample *)(w[2]);
168 t_biquadctl *c = (t_biquadctl *)(w[3]);
169 int n = (t_int)(w[4]);
170 int i;
171 t_sample last = c->c_x1;
172 t_sample prev = c->c_x2;
173 t_sample fb1 = c->c_fb1;
174 t_sample fb2 = c->c_fb2;
175 t_sample ff1 = c->c_ff1;
176 t_sample ff2 = c->c_ff2;
177 t_sample ff3 = c->c_ff3;
178 for (i = 0; i < n; i++)
179 {
180 t_sample output = *in++ + mult(fb1,last) + mult(fb2,prev);
181 if (PD_BADFLOAT(output))
182 output = 0;
183 *out++ = mult(ff1,output) + mult(ff2,last) + mult(ff3,prev);
184 prev = last;
185 last = output;
186 }
187 c->c_x1 = last;
188 c->c_x2 = prev;
189 return (w+5);
190}
191
192static void sigbiquad_list(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv)
193{
194 float fb1 = atom_getfloatarg(0, argc, argv);
195 float fb2 = atom_getfloatarg(1, argc, argv);
196 float ff1 = atom_getfloatarg(2, argc, argv);
197 float ff2 = atom_getfloatarg(3, argc, argv);
198 float ff3 = atom_getfloatarg(4, argc, argv);
199 float discriminant = fb1 * fb1 + 4 * fb2;
200 t_biquadctl *c = x->x_ctl;
201 if (discriminant < 0) /* imaginary roots -- resonant filter */
202 {
203 /* they're conjugates so we just check that the product
204 is less than one */
205 if (fb2 >= -1.0f) goto stable;
206 }
207 else /* real roots */
208 {
209 /* check that the parabola 1 - fb1 x - fb2 x^2 has a
210 vertex between -1 and 1, and that it's nonnegative
211 at both ends, which implies both roots are in [1-,1]. */
212 if (fb1 <= 2.0f && fb1 >= -2.0f &&
213 1.0f - fb1 -fb2 >= 0 && 1.0f + fb1 - fb2 >= 0)
214 goto stable;
215 }
216 /* if unstable, just bash to zero */
217 fb1 = fb2 = ff1 = ff2 = ff3 = 0;
218stable:
219 c->c_fb1 = ftofix(fb1);
220 c->c_fb2 = ftofix(fb2);
221 c->c_ff1 = ftofix(ff1);
222 c->c_ff2 = ftofix(ff2);
223 c->c_ff3 = ftofix(ff3);
224}
225
226static void sigbiquad_set(t_sigbiquad *x, t_symbol *s, int argc, t_atom *argv)
227{
228 t_biquadctl *c = x->x_ctl;
229 c->c_x1 = atom_getfloatarg(0, argc, argv);
230 c->c_x2 = atom_getfloatarg(1, argc, argv);
231}
232
233static void sigbiquad_dsp(t_sigbiquad *x, t_signal **sp)
234{
235 dsp_add(sigbiquad_perform, 4,
236 sp[0]->s_vec, sp[1]->s_vec,
237 x->x_ctl, sp[0]->s_n);
238
239}
240
241void biquad_tilde_setup(void)
242{
243 sigbiquad_class = class_new(gensym("biquad~"), (t_newmethod)sigbiquad_new,
244 0, sizeof(t_sigbiquad), 0, A_GIMME, 0);
245 CLASS_MAINSIGNALIN(sigbiquad_class, t_sigbiquad, x_f);
246 class_addmethod(sigbiquad_class, (t_method)sigbiquad_dsp, gensym("dsp"), 0);
247 class_addlist(sigbiquad_class, sigbiquad_list);
248 class_addmethod(sigbiquad_class, (t_method)sigbiquad_set, gensym("set"),
249 A_GIMME, 0);
250 class_addmethod(sigbiquad_class, (t_method)sigbiquad_set, gensym("clear"),
251 A_GIMME, 0);
252}
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-12 17:45:20 +0000