Fix changing process mode without quitting carla

source/carla_backend.py

@@ -1311,8 +1311,9 @@ class CarlaHostMeta(QObject):
         self.isPlugin  = False
 
         # settings
-        self.processMode   = ENGINE_PROCESS_MODE_CONTINUOUS_RACK
-        self.transportMode = ENGINE_TRANSPORT_MODE_INTERNAL
+        self.processMode       = ENGINE_PROCESS_MODE_CONTINUOUS_RACK
+        self.transportMode     = ENGINE_TRANSPORT_MODE_INTERNAL
+        self.nextProcessMode   = ENGINE_PROCESS_MODE_CONTINUOUS_RACK
         self.processModeForced = False
 
         # settings

source/carla_host.py

@@ -2107,12 +2107,14 @@ def loadHostSettings(host):
         except:
             host.processMode = CARLA_DEFAULT_PROCESS_MODE
 
+        host.nextProcessMode = host.processMode
+
     # --------------------------------------------------------------------------------------------------------
     # fix things if needed
 
     if host.processMode == ENGINE_PROCESS_MODE_MULTIPLE_CLIENTS and LADISH_APP_NAME:
         print("LADISH detected but using multiple clients (not allowed), forcing single client now")
-        host.processMode = ENGINE_PROCESS_MODE_SINGLE_CLIENT
+        host.nextProcessMode = host.processMode = ENGINE_PROCESS_MODE_SINGLE_CLIENT
 
 # ------------------------------------------------------------------------------------------------------------
 # Set host settings
@@ -2135,7 +2137,7 @@ def setHostSettings(host):
     if host.isPlugin:
         return
 
-    host.set_engine_option(ENGINE_OPTION_PROCESS_MODE,          host.processMode,         "")
+    host.set_engine_option(ENGINE_OPTION_PROCESS_MODE,          host.nextProcessMode,     "")
     host.set_engine_option(ENGINE_OPTION_TRANSPORT_MODE,        host.transportMode,       "")
 
 # ------------------------------------------------------------------------------------------------------------

source/carla_settings.py

@@ -348,10 +348,10 @@ class CarlaSettingsW(QDialog):
             self.ui.sw_engine_process_mode.setCurrentIndex(1)
             self.ui.tb_engine_driver_config.setEnabled(not self.host.isPlugin)
 
-        self.ui.cb_engine_process_mode_jack.setCurrentIndex(self.host.processMode)
+        self.ui.cb_engine_process_mode_jack.setCurrentIndex(self.host.nextProcessMode)
 
-        if self.host.processMode >= self.PROCESS_MODE_NON_JACK_PADDING:
-            self.ui.cb_engine_process_mode_other.setCurrentIndex(self.host.processMode-self.PROCESS_MODE_NON_JACK_PADDING)
+        if self.host.nextProcessMode >= self.PROCESS_MODE_NON_JACK_PADDING:
+            self.ui.cb_engine_process_mode_other.setCurrentIndex(self.host.nextProcessMode-self.PROCESS_MODE_NON_JACK_PADDING)
         else:
             self.ui.cb_engine_process_mode_other.setCurrentIndex(0)
 
@@ -458,11 +458,11 @@ class CarlaSettingsW(QDialog):
 
         if not self.host.processModeForced:
             # engine sends callback if processMode really changes
-            processMode = self.ui.cb_engine_process_mode_jack.currentIndex() if audioDriver == "JACK" else self.ui.cb_engine_process_mode_other.currentIndex()+self.PROCESS_MODE_NON_JACK_PADDING
+            self.host.nextProcessMode = self.ui.cb_engine_process_mode_jack.currentIndex() if audioDriver == "JACK" else self.ui.cb_engine_process_mode_other.currentIndex()+self.PROCESS_MODE_NON_JACK_PADDING
 
-            self.host.set_engine_option(ENGINE_OPTION_PROCESS_MODE, processMode, "")
+            self.host.set_engine_option(ENGINE_OPTION_PROCESS_MODE, self.host.nextProcessMode, "")
 
-            settings.setValue(CARLA_KEY_ENGINE_PROCESS_MODE, processMode)
+            settings.setValue(CARLA_KEY_ENGINE_PROCESS_MODE, self.host.nextProcessMode)
 
         self.host.forceStereo         = self.ui.ch_engine_force_stereo.isChecked()
         self.host.preferPluginBridges = self.ui.ch_engine_prefer_plugin_bridges.isChecked()