Fix IIR filter Q becoming negative (#1476)

Author: derselbst

src/rvoice/fluid_iir_filter.c

@@ -115,6 +115,7 @@ DECLARE_FLUID_RVOICE_FUNCTION(fluid_iir_filter_set_q)
     if(iir_filter->filter_startup)
     {
         iir_filter->last_q = q;
+        iir_filter->q_incr_count = 0;
     }
     else
     {
@@ -126,6 +127,7 @@ DECLARE_FLUID_RVOICE_FUNCTION(fluid_iir_filter_set_q)
         }
         iir_filter->q_incr = (q - iir_filter->last_q) / (q_incr_count);
         iir_filter->q_incr_count = q_incr_count;
+        LOG_FILTER("%f - %f / %f = %f", q , iir_filter->last_q, q_incr_count, iir_filter->q_incr);
     }
 #ifdef DBG_FILTER
     iir_filter->target_q = q;

src/utils/fluid_conv.c

@@ -211,7 +211,7 @@ fluid_real_t
 fluid_sec2tc(fluid_real_t sec)
 {
     fluid_real_t res;
-    if(sec < 0)
+    if(sec <= 0)
     {
         // would require a complex solution of fluid_tc2sec(), but this is real-only
         return -32768.f;