Added: VST Plugin support. Add and configure plugins via Configuration Editor. The plugin's architecture has to match the OS architecture, so most people will need 64-bit plugins. The subdirectory plugins is offered to put plugins into, but they can be opened from any directory with sufficient permissions.

Fixed: When trying to add a high-pass filter in the Configuration Editor, it was instead configured to be a low-pass filter.

helpers/VSTPluginLibrary.h

@@ -0,0 +1,49 @@
+/*
+    This file is part of Equalizer APO, a system-wide equalizer.
+    Copyright (C) 2017  Jonas Thedering
+
+    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 2 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, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#pragma once
+
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include "AbstractLibrary.h"
+#include "aeffectx.h"
+#include <queue>
+#include "VSTPluginInstance.h"
+
+class VSTPluginLibrary : public AbstractLibrary
+{
+public:
+	static std::shared_ptr<VSTPluginLibrary> getInstance(const std::wstring& libPath);
+	static std::wstring getDefaultPluginPath();
+
+	std::wstring getLibPath() override;
+
+	typedef AEffect* (* vstPluginMain)(audioMasterCallback audioMaster);
+	vstPluginMain VSTPluginMain;
+
+protected:
+	bool loadFunctions() override;
+
+private:
+	VSTPluginLibrary(const std::wstring& libPath);
+	static std::unordered_map<std::wstring, std::weak_ptr<VSTPluginLibrary> > instanceMap;
+	static std::wstring defaultPluginPath;
+	std::wstring libPath;
+};