1 files changed, 52 insertions, 0 deletions
diff --git a/cyclone/sickle/delta.c b/cyclone/sickle/delta.c
new file mode 100644
index 0000000..145d6b7
--- /dev/null
+++ b/cyclone/sickle/delta.c
@@ -0,0 +1,52 @@
+/* Copyright (c) 2002-2003 krzYszcz and others.
+ * For information on usage and redistribution, and for a DISCLAIMER OF ALL
+ * WARRANTIES, see the file, "LICENSE.txt," in this distribution.  */
+
+#include "m_pd.h"
+#include "sickle/sic.h"
+
+typedef struct _delta
+{
+    t_sic    x_sic;
+    t_float  x_last;
+} t_delta;
+
+static t_class *delta_class;
+
+static t_int *delta_perform(t_int *w)
+{
+    t_delta *x = (t_delta *)(w[1]);
+    int nblock = (int)(w[2]);
+    t_float *in = (t_float *)(w[3]);
+    t_float *out = (t_float *)(w[4]);
+    t_float last = x->x_last;
+    while (nblock--)
+    {
+	t_float f = *in++;
+    	*out++ = f - last;
+	last = f;
+    }
+    x->x_last = last;
+    return (w + 5);
+}
+
+static void delta_dsp(t_delta *x, t_signal **sp)
+{
+    dsp_add(delta_perform, 4, x, sp[0]->s_n, sp[0]->s_vec, sp[1]->s_vec);
+}
+
+static void *delta_new(void)
+{
+    t_delta *x = (t_delta *)pd_new(delta_class);
+    outlet_new((t_object *)x, &s_signal);
+    x->x_last = 0;
+    return (x);
+}
+
+void delta_tilde_setup(void)
+{
+    delta_class = class_new(gensym("delta~"),
+			    (t_newmethod)delta_new, 0,
+			    sizeof(t_delta), 0, 0);
+    sic_setup(delta_class, delta_dsp, SIC_FLOATTOSIGNAL);
+}