/* Cached parameters for our interpolation polynomial y=ax^3+b^2+cx */
double a, b, c;
- pa_bool_t abc_valid;
+ pa_bool_t abc_valid:1;
pa_bool_t monotonic:1;
pa_bool_t paused:1;
+ pa_bool_t smoothing:1; /* If FALSE we skip the polonyomial interpolation step */
pa_usec_t pause_time;
unsigned min_history;
};
-pa_smoother* pa_smoother_new(pa_usec_t adjust_time, pa_usec_t history_time, pa_bool_t monotonic, unsigned min_history) {
+pa_smoother* pa_smoother_new(
+ pa_usec_t adjust_time,
+ pa_usec_t history_time,
+ pa_bool_t monotonic,
+ pa_bool_t smoothing,
+ unsigned min_history,
+ pa_usec_t time_offset,
+ pa_bool_t paused) {
+
pa_smoother *s;
pa_assert(adjust_time > 0);
s = pa_xnew(pa_smoother, 1);
s->adjust_time = adjust_time;
s->history_time = history_time;
- s->time_offset = 0;
+ s->min_history = min_history;
s->monotonic = monotonic;
+ s->smoothing = smoothing;
- s->px = s->py = 0;
- s->dp = 1;
-
- s->ex = s->ey = s->ry = 0;
- s->de = 1;
-
- s->history_idx = 0;
- s->n_history = 0;
-
- s->last_y = s->last_x = 0;
-
- s->abc_valid = FALSE;
-
- s->paused = FALSE;
-
- s->min_history = min_history;
+ pa_smoother_reset(s, time_offset, paused);
return s;
}
int64_t ax = 0, ay = 0, k, t;
double r;
+ /* FIXME: Optimization: Jason Newton suggested that instead of
+ * going through the history on each iteration we could calculated
+ * avg_gradient() as we go.
+ *
+ * Second idea: it might make sense to weight history entries:
+ * more recent entries should matter more than old ones. */
+
/* Too few measurements, assume gradient of 1 */
if (s->n_history < s->min_history)
return 1;
pa_assert(y);
if (x >= s->px) {
+ /* Linear interpolation right from px */
int64_t t;
/* The requested point is right of the point where we wanted
if (deriv)
*deriv = s->dp;
+ } else if (x <= s->ex) {
+ /* Linear interpolation left from ex */
+ int64_t t;
+
+ t = (int64_t) s->ey - (int64_t) llrint(s->de * (double) (s->ex - x));
+
+ if (t < 0)
+ t = 0;
+
+ *y = (pa_usec_t) t;
+
+ if (deriv)
+ *deriv = s->de;
+
} else {
+ /* Spline interpolation between ex and px */
double tx, ty;
/* Ok, we're not yet on track, thus let's interpolate, and
calc_abc(s);
- tx = (double) x;
-
/* Move to origin */
- tx -= (double) s->ex;
+ tx = (double) (x - s->ex);
/* Horner scheme */
ty = (tx * (s->c + tx * (s->b + tx * s->a)));
* we can adjust our position smoothly from this one */
estimate(s, x, &ney, &nde);
s->ex = x; s->ey = ney; s->de = nde;
-
s->ry = y;
}
s->dp = avg_gradient(s, x);
/* And calculate when we want to be on track again */
- s->px = s->ex + s->adjust_time;
- s->py = s->ry + (pa_usec_t) llrint(s->dp * (double) s->adjust_time);
+ if (s->smoothing) {
+ s->px = s->ex + s->adjust_time;
+ s->py = s->ry + (pa_usec_t) llrint(s->dp * (double) s->adjust_time);
+ } else {
+ s->px = s->ex;
+ s->py = s->ry;
+ }
s->abc_valid = FALSE;
-/* pa_log_debug("put(%llu | %llu) = %llu", (unsigned long long) (x + s->time_offset), (unsigned long long) x, (unsigned long long) y); */
+#ifdef DEBUG_DATA
+ pa_log_debug("%p, put(%llu | %llu) = %llu", s, (unsigned long long) (x + s->time_offset), (unsigned long long) x, (unsigned long long) y);
+#endif
}
pa_usec_t pa_smoother_get(pa_smoother *s, pa_usec_t x) {
s->last_y = y;
}
-/* pa_log_debug("get(%llu | %llu) = %llu", (unsigned long long) (x + s->time_offset), (unsigned long long) x, (unsigned long long) y); */
+#ifdef DEBUG_DATA
+ pa_log_debug("%p, get(%llu | %llu) = %llu", s, (unsigned long long) (x + s->time_offset), (unsigned long long) x, (unsigned long long) y);
+#endif
return y;
}
s->time_offset = offset;
-/* pa_log_debug("offset(%llu)", (unsigned long long) offset); */
+#ifdef DEBUG_DATA
+ pa_log_debug("offset(%llu)", (unsigned long long) offset);
+#endif
}
void pa_smoother_pause(pa_smoother *s, pa_usec_t x) {
if (s->paused)
return;
-/* pa_log_debug("pause(%llu)", (unsigned long long) x); */
+#ifdef DEBUG_DATA
+ pa_log_debug("pause(%llu)", (unsigned long long) x);
+#endif
s->paused = TRUE;
s->pause_time = x;
}
-void pa_smoother_resume(pa_smoother *s, pa_usec_t x) {
+void pa_smoother_resume(pa_smoother *s, pa_usec_t x, pa_bool_t fix_now) {
pa_assert(s);
if (!s->paused)
if (x < s->pause_time)
x = s->pause_time;
-/* pa_log_debug("resume(%llu)", (unsigned long long) x); */
+#ifdef DEBUG_DATA
+ pa_log_debug("resume(%llu)", (unsigned long long) x);
+#endif
s->paused = FALSE;
s->time_offset += x - s->pause_time;
+
+ if (fix_now)
+ pa_smoother_fix_now(s);
+}
+
+void pa_smoother_fix_now(pa_smoother *s) {
+ pa_assert(s);
+
+ s->px = s->ex;
+ s->py = s->ry;
}
pa_usec_t pa_smoother_translate(pa_smoother *s, pa_usec_t x, pa_usec_t y_delay) {
if (s->dp > nde)
nde = s->dp;
-/* pa_log_debug("translate(%llu) = %llu (%0.2f)", (unsigned long long) y_delay, (unsigned long long) ((double) y_delay / nde), nde); */
+#ifdef DEBUG_DATA
+ pa_log_debug("translate(%llu) = %llu (%0.2f)", (unsigned long long) y_delay, (unsigned long long) ((double) y_delay / nde), nde);
+#endif
return (pa_usec_t) llrint((double) y_delay / nde);
}
-void pa_smoother_reset(pa_smoother *s) {
+void pa_smoother_reset(pa_smoother *s, pa_usec_t time_offset, pa_bool_t paused) {
pa_assert(s);
+ s->px = s->py = 0;
+ s->dp = 1;
+
+ s->ex = s->ey = s->ry = 0;
+ s->de = 1;
+
+ s->history_idx = 0;
s->n_history = 0;
+
+ s->last_y = s->last_x = 0;
+
s->abc_valid = FALSE;
+
+ s->paused = paused;
+ s->time_offset = s->pause_time = time_offset;
+
+#ifdef DEBUG_DATA
+ pa_log_debug("reset()");
+#endif
}