Changeset 5186:9667c5a66a36 in roaraudio for roarclients

Timestamp:

10/22/11 20:06:20 (12 years ago)

Author:

phi

Branch:

default

Phase:

public

Message:

added code to enable endless generation without accuracy errors

File:

• roarclients/roarsin.c (modified) (2 diffs)

roarclients/roarsin.c

@@ -80 +80 @@
  float freq   = 523.2;            /* middle C */
  float t      = 0; /* current time */
+ float tcalc  = 0; /* current time for calculation */
  float length = 5; /* 5 sec */
  float step;       /* how much time per sample we have to encode ... */
@@ -117 +118 @@
  while (t < 2*M_PI*freq*length) {
   for (i = 0; i < 1024; i++) {
-   out[i] = 32767*func(t);
-   t += step;
+   out[i] = 32767*func(tcalc);
+   t     += step;
+   tcalc += step;
   }
   roar_vs_write(vss, out, 2048, NULL);
+
+  // this code enables us to generate the same signal for a long periode of time
+  // without loosing accuracy of the float type.
+  while (tcalc > 2*M_PI)
+   tcalc -= 2*M_PI;
  }