From 45b69bc01f77c848c745f0808df322a6d2a64858 Mon Sep 17 00:00:00 2001
From: David Schornsheim <david@u-he.com>
Date: Mon, 26 Feb 2024 12:17:35 +0100
Subject: [PATCH] Store missed latency call and report after activate()

---
 src/wrapasvst3.cpp | 19 ++++++++++++++++---
 src/wrapasvst3.h   |  1 +
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/wrapasvst3.cpp b/src/wrapasvst3.cpp
index 234c742f..a699b410 100644
--- a/src/wrapasvst3.cpp
+++ b/src/wrapasvst3.cpp
@@ -87,6 +87,11 @@ tresult PLUGIN_API ClapAsVst3::setActive(TBool state)
         _expressionmap & clap_supported_note_expressions::AS_VST3_NOTE_EXPRESSION_TUNING);
     updateAudioBusses();
 
+    if (_missedLatencyRequest)
+    {
+      latency_changed();
+    }
+
     _os_attached.on();
   }
   if (!state)
@@ -132,11 +137,19 @@ tresult PLUGIN_API ClapAsVst3::getState(IBStream* state)
 
 uint32 PLUGIN_API ClapAsVst3::getLatencySamples()
 {
-  if (_plugin->_ext._latency && _active)
+  if (!_plugin->_ext._latency)
   {
-    return _plugin->_ext._latency->get(_plugin->_plugin);
+    return 0;
   }
-  return 0;
+
+  if (!_active)
+  {
+    _missedLatencyRequest = true;
+    return 0;
+  }
+
+  _missedLatencyRequest = false;
+  return _plugin->_ext._latency->get(_plugin->_plugin);
 }
 
 uint32 PLUGIN_API ClapAsVst3::getTailSamples()
diff --git a/src/wrapasvst3.h b/src/wrapasvst3.h
index 7ce4f8c2..dca1a788 100644
--- a/src/wrapasvst3.h
+++ b/src/wrapasvst3.h
@@ -259,6 +259,7 @@ class ClapAsVst3 : public Steinberg::Vst::SingleComponentEffect,
   std::mutex _processingLock;
   std::atomic_bool _requestedFlush = false;
   std::atomic_bool _requestUICallback = false;
+  bool _missedLatencyRequest = false;
 
   // the queue from audiothread to UI thread
   ClapWrapper::detail::shared::fixedqueue<queueEvent, 8192> _queueToUI;