implement CV and control trigger

src/zlfo.c

@@ -34,6 +34,7 @@
 
 #define IS_FREERUN(x) (*x->freerun > 0.001f)
 #define IS_STEP_MODE(x) (*x->step_mode > 0.001f)
+#define IS_TRIGGERED(x) (*x->trigger > 0.001f)
 
 typedef struct ZLFO
 {
@@ -489,6 +490,17 @@ run (
     ((float) self->common.period_size /
      grid_step_divisor);
 
+  /* handle triggers
+   *
+   * FIXME CV trigger requires splitting the cycle,
+   * but for now it applies to the whole cycle */
+  if (IS_TRIGGERED (self) ||
+      float_array_contains_nonzero (
+        self->cv_trigger, n_samples))
+    {
+      self->common.current_sample = 0;
+    }
+
   for (uint32_t i = 0; i < n_samples; i++)
     {
       /* invert horizontally */

src/zlfo_math.h

@@ -254,17 +254,18 @@ get_current_sample (
   HostPosition * host_pos,
   uint32_t       period_size)
 {
-  /* if beat_unit is 0 that means we don't know the
-   * time info yet */
-  if (freerunning || host_pos->beat_unit == 0)
+  if (freerunning)
     {
-      if (!freerunning && host_pos->beat_unit == 0)
-        {
-          fprintf (
-            stderr,
-            "Host did not send time info. Beat "
-            "unit is unknown.\n");
-        }
+      return 0;
+    }
+  else if (host_pos->beat_unit == 0)
+    {
+      /* if beat_unit is 0 that means we don't
+       * know the time info yet */
+      fprintf (
+        stderr,
+        "Host did not send time info. Beat "
+        "unit is unknown.\n");
       return 0;
     }
   else /* synced */
@@ -273,6 +274,20 @@ get_current_sample (
     }
 }
 
+static inline int
+float_array_contains_nonzero (
+  const float * arr,
+  size_t        size)
+{
+  for (size_t i = 0; i < size; i++)
+    {
+      if (arr[i] > 0.0001f ||
+          arr[i] < - 0.0001f)
+        return 1;
+    }
+  return 0;
+}
+
 /**
  * @param sine_multipler Position to save the sine
  *   multiplier in.

src/zlfo_ttl_gen.c

@@ -122,7 +122,7 @@ int main (
     lv2:default %f ;\n\
     lv2:minimum %f ;\n\
     lv2:maximum %f ;\n\
-  ] , [\n", 0.0, -1.0, 1.0, 0.0, -1.0, 1.0);
+  ] , [\n", 0.0, 0.0, 1.0, 0.0, 0.0, 1.0);
 
   /* write input controls */
   int index = ZLFO_GATE;