diff --git a/meson.build b/meson.build
index f3eb0d53..51a60d63 100644
--- a/meson.build
+++ b/meson.build
@@ -115,6 +115,7 @@ vst3_plugin_sources = [
'src/common/serialization/vst3/component-handler/component-handler-2.cpp',
'src/common/serialization/vst3/component-handler/component-handler-3.cpp',
'src/common/serialization/vst3/component-handler/unit-handler.cpp',
+ 'src/common/serialization/vst3/component-handler/unit-handler-2.cpp',
'src/common/serialization/vst3/context-menu/context-menu.cpp',
'src/common/serialization/vst3/host-context/host-application.cpp',
'src/common/serialization/vst3/plug-view/parameter-finder.cpp',
@@ -190,6 +191,7 @@ if with_vst3
'src/common/serialization/vst3/component-handler/component-handler-2.cpp',
'src/common/serialization/vst3/component-handler/component-handler-3.cpp',
'src/common/serialization/vst3/component-handler/unit-handler.cpp',
+ 'src/common/serialization/vst3/component-handler/unit-handler-2.cpp',
'src/common/serialization/vst3/context-menu/context-menu.cpp',
'src/common/serialization/vst3/host-context/host-application.cpp',
'src/common/serialization/vst3/plug-view/parameter-finder.cpp',
diff --git a/src/common/serialization/vst3/README.md b/src/common/serialization/vst3/README.md
index 9b22ab21..90f0f752 100644
--- a/src/common/serialization/vst3/README.md
+++ b/src/common/serialization/vst3/README.md
@@ -6,7 +6,8 @@ for more information on how the serialization works.
The following interfaces are not yet implemented:
-- Every interface introduced after VST 3.6.0
+- Interfaces introduced after VST 3.6.0, with some VST 3.6.5 interfaces already
+ being implemented
- The [Presonus extensions](https://presonussoftware.com/en_US/developer),
although most of these things seem to overlap with newer VST3 interfaces
@@ -48,6 +49,7 @@ VST3 host interfaces are implemented as follows:
| `YaComponentHandler2` | `Vst3ComponentHandlerProxy` | `IComponentHandler2` |
| `YaComponentHandler3` | `Vst3ComponentHandlerProxy` | `IComponentHandler3` |
| `YaUnitHandler` | `Vst3ComponentHandlerProxy` | `IUnitHandler` |
+| `YaUnitHandler2` | `Vst3ComponentHandlerProxy` | `IUnitHandler2` |
| `Vst3ContextMenuProxy` | | All of the below: |
| `YaContextMenu` | `Vst3ContextMenuProxy` | `IContextMenu` |
| `Vst3PlugFrameProxy` | | All of the below: |
diff --git a/src/common/serialization/vst3/component-handler/unit-handler-2.cpp b/src/common/serialization/vst3/component-handler/unit-handler-2.cpp
new file mode 100644
index 00000000..2a92276e
--- /dev/null
+++ b/src/common/serialization/vst3/component-handler/unit-handler-2.cpp
@@ -0,0 +1,27 @@
+// yabridge: a Wine VST bridge
+// Copyright (C) 2020-2021 Robbert van der Helm
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see .
+
+#include "unit-handler-2.h"
+
+YaUnitHandler2::ConstructArgs::ConstructArgs() {}
+
+YaUnitHandler2::ConstructArgs::ConstructArgs(
+ Steinberg::IPtr object)
+ : supported(Steinberg::FUnknownPtr(object)) {
+}
+
+YaUnitHandler2::YaUnitHandler2(const ConstructArgs&& args)
+ : arguments(std::move(args)) {}
diff --git a/src/common/serialization/vst3/component-handler/unit-handler-2.h b/src/common/serialization/vst3/component-handler/unit-handler-2.h
new file mode 100644
index 00000000..e2362c59
--- /dev/null
+++ b/src/common/serialization/vst3/component-handler/unit-handler-2.h
@@ -0,0 +1,70 @@
+// yabridge: a Wine VST bridge
+// Copyright (C) 2020-2021 Robbert van der Helm
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see .
+
+#pragma once
+
+#include
+
+#include "../../common.h"
+#include "../base.h"
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+
+/**
+ * Wraps around `IUnitHandler2` for serialization purposes. This is instantiated
+ * as part of `Vst3UnitHandler2Proxy`.
+ */
+class YaUnitHandler2 : public Steinberg::Vst::IUnitHandler2 {
+ public:
+ /**
+ * These are the arguments for creating a `YaUnitHandler2`.
+ */
+ struct ConstructArgs {
+ ConstructArgs();
+
+ /**
+ * Check whether an existing implementation implements `IUnitHandler2`
+ * and read arguments from it.
+ */
+ ConstructArgs(Steinberg::IPtr object);
+
+ /**
+ * Whether the object supported this interface.
+ */
+ bool supported;
+
+ template
+ void serialize(S& s) {
+ s.value1b(supported);
+ }
+ };
+
+ /**
+ * Instantiate this instance with arguments read from another interface
+ * implementation.
+ */
+ YaUnitHandler2(const ConstructArgs&& args);
+
+ inline bool supported() const { return arguments.supported; }
+
+ virtual tresult PLUGIN_API notifyUnitByBusChange() override = 0;
+
+ protected:
+ ConstructArgs arguments;
+};
+
+#pragma GCC diagnostic pop