improved timing acq

src/model.cpp

@@ -358,6 +358,20 @@ void ScopeModel::live_window_locked(double lo_s, double hi_s, u64& first, u64& l
   if (last < first) last = first;
 }
 
+void ScopeModel::reset_live_history() {
+  std::lock_guard<std::mutex> lock(mutex_);
+  reset_live_history_locked();
+}
+
+void ScopeModel::reset_live_history_locked() {
+  BufferStore& src = live();
+  src.time().clear();
+  for (std::size_t c = 0; c < channels_.size(); ++c) {
+    src.values(c).clear();
+    src.channel(c).invalidate();
+  }
+}
+
 void ScopeModel::publish_event(double pre_s, double post_s, double edge) {
   auto snap = std::make_shared<EventSnapshot>();
   BufferStore& src = live();