Initial release

engine/vendor/vst3sdk/public.sdk/source/vst/hosting/parameterchanges.h

@@ -0,0 +1,122 @@
+//-----------------------------------------------------------------------------
+// Project     : VST SDK
+//
+// Category    : Helpers
+// Filename    : public.sdk/source/vst/hosting/parameterchanges.h
+// Created by  : Steinberg, 03/05/2008.
+// Description : VST 3 parameter changes implementation
+//
+//-----------------------------------------------------------------------------
+// This file is part of a Steinberg SDK. It is subject to the license terms
+// in the LICENSE file found in the top-level directory of this distribution
+// and at www.steinberg.net/sdklicenses.
+// No part of the SDK, including this file, may be copied, modified, propagated,
+// or distributed except according to the terms contained in the LICENSE file.
+//-----------------------------------------------------------------------------
+
+#pragma once
+
+#include "pluginterfaces/vst/ivstparameterchanges.h"
+#include <vector>
+
+namespace Steinberg {
+namespace Vst {
+
+//------------------------------------------------------------------------
+/** Implementation's example of IParamValueQueue - not threadsave!.
+\ingroup hostingBase
+*/
+class ParameterValueQueue : public IParamValueQueue
+{
+public:
+	//------------------------------------------------------------------------
+	ParameterValueQueue (ParamID paramID);
+	virtual ~ParameterValueQueue ();
+
+	ParamID PLUGIN_API getParameterId () SMTG_OVERRIDE { return paramID; }
+	int32 PLUGIN_API getPointCount () SMTG_OVERRIDE;
+	tresult PLUGIN_API getPoint (int32 index, int32& sampleOffset, ParamValue& value) SMTG_OVERRIDE;
+	tresult PLUGIN_API addPoint (int32 sampleOffset, ParamValue value, int32& index) SMTG_OVERRIDE;
+
+	void setParamID (ParamID pID) {paramID = pID;}
+	void clear ();
+	//------------------------------------------------------------------------
+	DECLARE_FUNKNOWN_METHODS
+protected:
+	ParamID paramID;
+
+	struct ParameterQueueValue
+	{
+		ParameterQueueValue (ParamValue value, int32 sampleOffset) : value (value), sampleOffset (sampleOffset) {}
+		ParamValue value;
+		int32 sampleOffset;
+	};
+	std::vector<ParameterQueueValue> values;
+};
+
+//------------------------------------------------------------------------
+/** Implementation's example of IParameterChanges - not threadsave!.
+\ingroup hostingBase
+*/
+class ParameterChanges : public IParameterChanges
+{
+public:
+	//------------------------------------------------------------------------
+	ParameterChanges (int32 maxParameters = 0);
+	virtual ~ParameterChanges ();
+
+	void clearQueue ();
+	void setMaxParameters (int32 maxParameters);
+
+	//---IParameterChanges-----------------------------
+	int32 PLUGIN_API getParameterCount () SMTG_OVERRIDE;
+	IParamValueQueue* PLUGIN_API getParameterData (int32 index) SMTG_OVERRIDE;
+	IParamValueQueue* PLUGIN_API addParameterData (const ParamID& pid, int32& index) SMTG_OVERRIDE;
+	
+	//------------------------------------------------------------------------
+	DECLARE_FUNKNOWN_METHODS
+protected:
+	std::vector<IPtr<ParameterValueQueue>> queues;
+	int32 usedQueueCount {0};
+};
+
+
+//------------------------------------------------------------------------
+/** Ring buffer for transferring parameter changes from a writer to a read thread .
+\ingroup hostingBase
+*/
+class ParameterChangeTransfer
+{
+public:
+	//------------------------------------------------------------------------
+	ParameterChangeTransfer (int32 maxParameters = 0);
+	virtual ~ParameterChangeTransfer ();
+
+	void setMaxParameters (int32 maxParameters);
+
+	void addChange (ParamID pid, ParamValue value, int32 sampleOffset);
+	bool getNextChange (ParamID& pid, ParamValue& value, int32& sampleOffset);
+
+	void transferChangesTo (ParameterChanges& dest);
+	void transferChangesFrom (ParameterChanges& source);
+
+	void removeChanges () { writeIndex = readIndex; }
+
+	//------------------------------------------------------------------------
+protected:
+	struct ParameterChange
+	{
+		ParamID id;
+		ParamValue value;
+		int32 sampleOffset;
+	};
+	int32 size;
+	ParameterChange* changes;
+
+	volatile int32 readIndex;
+	volatile int32 writeIndex;
+};
+
+//------------------------------------------------------------------------
+} // namespace Vst
+} // namespace Steinberg