Send events on parameter gesture/change

crunch.h

@@ -28,13 +28,14 @@ struct CrunchSTFX : public BaseEffect {
 	static constexpr int oversampleHalfLatency = 16;
 	static constexpr Sample autoGainLevel = 0.1;
 
-	ParamRange drive{4};
+	const bool autoGain;
+
+	ParamRange drive{stfx::units::dbToGain(autoGain ? 24 : 12)};
 	ParamRange fuzz{0};
 	ParamRange toneHz{2000};
 	ParamRange cutHz{50};
 	ParamRange outGain{1};
 
-	const bool autoGain;
 	CrunchSTFX(bool autoGain=true) : autoGain(autoGain) {}
 
 	template<class Storage>

stfx/clap/stfx-clap.h

@@ -8,7 +8,7 @@
 #include <optional>
 
 #include "../param-info.h"
-#include "../storage/storage.h"
+#include "../storage/stfx-storage.h"
 #include "../ui/web-ui.h"
 
 namespace stfx { namespace clap {
@@ -133,6 +133,7 @@ template<template<class> class EffectSTFX>
 struct Plugin : public clap_plugin {
 	const Plugins &plugins;
 	const clap_host *host;
+	const clap_host_params *hostParams = nullptr;
 	const clap_host_webview1 *hostWebview1 = nullptr;
 	using Effect = stfx::web::WebUILibraryEffect<float, EffectSTFX>;
 	Effect effect;
@@ -152,16 +153,6 @@ struct Plugin : public clap_plugin {
 		this->get_extension = plugin_get_extension;
 		this->on_main_thread = plugin_on_main_thread;
 		
-		effect.paramListenerRange = [&](stfx::web::ParamContext context, double v){
-			std::cout << "param #" << context.index << " change: " << v << "\n";
-		};
-		effect.paramListenerGesture = [&](stfx::web::ParamContext context, bool gesture){
-			std::cout << "param #" << context.index << " gesture: " << gesture << "\n";
-		};
-		effect.paramListenerStepped = [&](stfx::web::ParamContext context, int v){
-			std::cout << "param #" << context.index << " change: " << v << "\n";
-		};
-		
 		scanParams();
 	}
 
@@ -207,6 +198,7 @@ struct Plugin : public clap_plugin {
 		auto &plugin = *(Plugin *)obj;
 #define STFX_GET_EXT(field, extId) \
 		plugin.field = (decltype(plugin.field))plugin.host->get_extension(plugin.host, extId);
+		STFX_GET_EXT(hostParams, CLAP_EXT_PARAMS)
 		STFX_GET_EXT(hostWebview1, CLAP_EXT_WEBVIEW1)
 #undef STFX_GET_EXT
 		return true;
@@ -319,11 +311,10 @@ struct Plugin : public clap_plugin {
 		inputBuffers.resize(0);
 		outputBuffers.resize(0);
 
-plugin.host->request_callback(plugin.host);
-
 		if (plugin.effect.hasPendingWebMessage()) {
 			plugin.host->request_callback(plugin.host);
 		}
+		plugin.sendParamEvents(process->out_events);
 		return CLAP_PROCESS_CONTINUE;
 	}
 	static void plugin_on_main_thread(const clap_plugin *obj) {
@@ -337,6 +328,13 @@ plugin.host->request_callback(plugin.host);
 		std::optional<RangeParamInfo> rangeInfo;
 		typename Effect::ParamStepped *steppedParam = nullptr;
 		std::optional<SteppedParamInfo> steppedInfo;
+		
+		std::atomic_flag hostValueSent = ATOMIC_FLAG_INIT;
+		std::atomic_flag hostStartGestureSent = ATOMIC_FLAG_INIT;
+		std::atomic_flag hostStopGestureSent = ATOMIC_FLAG_INIT;
+		
+		Param() {}
+		Param(Param &&other) : clap_param_info(other), rangeParam(other.rangeParam), rangeInfo(std::move(other.rangeInfo)), steppedParam(other.steppedParam), steppedInfo(std::move(other.steppedInfo)) {}
 	
 		void setClapInfo() {
 			flags |= CLAP_PARAM_IS_AUTOMATABLE;
@@ -354,33 +352,22 @@ plugin.host->request_callback(plugin.host);
 				max_value = steppedInfo->high;
 				default_value = steppedInfo->defaultValue;
 			}
+			
+			hostValueSent.test_and_set();
+			hostStartGestureSent.test_and_set();
+			hostStopGestureSent.test_and_set();
 		}
 	};
 	std::vector<Param> params;
-	struct ParamScanner {
+	struct ParamScanner : public storage::STFXStorageScanner<ParamScanner> {
 		std::vector<Param> &params;
 		Crc32 crc;
 		
-		// Do nothing for most types
-		template<class V>
-		void operator()(const char *key, V &v) {
-			LOG_EXPR(key);
-			if constexpr (std::is_void_v<decltype(v.state(*this))>) {
-				LOG_EXPR("recursing");
-				ParamScanner recurse{*this};
-				recurse.crc.addString(key, true);
-				v.state(recurse);
-			}
-		}
+		ParamScanner(std::vector<Param> &params) : params(params) {}
 		
-		// Extra methods we add for STFX storage
-		void info(const char *, const char *) {}
-		int version(int v) {
-			return v;
-		}
 		template<class PR>
 		RangeParamInfo & range(const char *key, PR &param) {
-			param.context.index = params.size();
+			param.context.index = params.size(); // so we can find it in the listeners below
 			params.emplace_back();
 			auto &entry = params.back();
 			entry.id = crc.copy().addString(key, true).done();
@@ -389,25 +376,90 @@ plugin.host->request_callback(plugin.host);
 		}
 		template<class PS>
 		SteppedParamInfo & stepped(const char *key, PS &param) {
-			param.context.index = params.size();
+			param.context.index = params.size(); // so we can find it in the listeners below
+			
 			params.emplace_back();
 			auto &entry = params.back();
 			entry.id = crc.copy().addString(key, true).done();
 			entry.steppedParam = &param;
 			return entry.steppedInfo.emplace(param);
 		}
-		template<class V>
-		bool changed(const char *key, V &v) {
-			(*this)(key, v);
-			return false;
-		}
-		void invalidate(const char *) {}
 	};
 	void scanParams() {
-		params.resize(0);
+		params.clear();
 		ParamScanner scanner{params};
 		effect.state(scanner);
 		for (auto &entry : params) entry.setClapInfo();
+		
+		// Listen for changes from the effect UI
+		effect.paramListenerRange = [&](stfx::web::ParamContext context, double value){
+			params[context.index].hostValueSent.clear();
+			if (hostParams) hostParams->request_flush(host);
+		};
+		effect.paramListenerGesture = [&](stfx::web::ParamContext context, bool gesture){
+			if (gesture) {
+				params[context.index].hostStartGestureSent.clear();
+			} else {
+				params[context.index].hostStopGestureSent.clear();
+			}
+			if (hostParams) hostParams->request_flush(host);
+		};
+		effect.paramListenerStepped = [&](stfx::web::ParamContext context, int value){
+			params[context.index].hostValueSent.clear();
+			if (hostParams) hostParams->request_flush(host);
+		};
+	}
+	void sendParamEvents(const clap_output_events *events) {
+		for (auto &param : params) {
+			auto sendGesture = [&](uint16_t eventType){
+				clap_event_param_gesture event{
+					.header={
+						.size=sizeof(event),
+						.time=0,
+						.space_id=CLAP_CORE_EVENT_SPACE_ID,
+						.type=eventType
+					},
+					.param_id=param.id,
+				};
+				LOG_EXPR(event.header.type);
+				// Not *super* bothered if this fails
+				events->try_push(events, &event.header);
+			};
+			
+			if (!param.hostStartGestureSent.test_and_set()) {
+				sendGesture(CLAP_EVENT_PARAM_GESTURE_BEGIN);
+			}
+			if (!param.hostValueSent.test_and_set()) {
+				clap_event_param_value event{
+					.header={
+						.size=sizeof(event),
+						.time=0,
+						.space_id=CLAP_CORE_EVENT_SPACE_ID,
+						.type=CLAP_EVENT_PARAM_VALUE
+					},
+					.param_id=param.id,
+					.cookie=param.cookie,
+					.note_id=-1,
+					.port_index=-1,
+					.channel=-1,
+					.key=-1
+				};
+				LOG_EXPR(event.header.type);
+				if (param.rangeParam) {
+					event.value = param.rangeInfo->toUnit((double)*param.rangeParam);
+				} else {
+					event.value = (int)*param.steppedParam;
+				}
+				if (!events->try_push(events, &event.header)) {
+					// failed, try again later
+					param.hostValueSent.clear();
+					continue;
+				}
+			}
+			if (!param.hostStopGestureSent.test_and_set()) {
+				sendGesture(CLAP_EVENT_PARAM_GESTURE_END);
+			}
+		}
 	}
 	
 	// CLAP parameter methods
@@ -430,6 +482,7 @@ plugin.host->request_callback(plugin.host);
 				} else {
 					*value = (int)*param.steppedParam;
 				}
+				param.hostValueSent.test_and_set();
 				return true;
 			}
 		}
@@ -473,6 +526,7 @@ plugin.host->request_callback(plugin.host);
 			auto *header = inEvents->get(inEvents, i);
 			plugin.processEvent(header);
 		}
+		plugin.sendParamEvents(outEvents);
 	}
 	
 	// CLAP audio port methods
@@ -557,80 +611,19 @@ plugin.host->request_callback(plugin.host);
 			chunkSize = buffer.size();
 		}
 	}
-	
-	struct StateWriter : public stfx::storage::StorageCborWriter<true, StateWriter> {
-		using stfx::storage::StorageCborWriter<true, StateWriter>::StorageCborWriter;
-		
-		void info(const char *, const char *) {}
-		int version(int v) {
-			(*this)("version", v);
-			return v;
-		}
-		template<class RP>
-		RangeParamIgnore range(const char *key, RP &param) {
-			double v = param;
-			(*this)(key, v);
-			return {};
-		}
-		template<class SP>
-		SteppedParamIgnore stepped(const char *key, SP &param) {
-			int v = param;
-			(*this)(key, v);
-			return {};
-		}
-		template<class V>
-		bool changed(const char *key, V &v) {
-			(*this)(key, v);
-			return false;
-		}
-		void invalidate(const char *) {}
-	};
-	struct StateReader : public stfx::storage::StorageCborReader<true, StateReader> {
-		using stfx::storage::StorageCborReader<true, StateReader>::StorageCborReader;
-		
-		void info(const char *, const char *) {}
-		int version(int v) {
-			(*this)("version", v);
-			return v;
-		}
-		template<class RP>
-		RangeParamIgnore range(const char *key, RP &param) {
-			double v = param;
-			(*this)(key, v);
-			param = v;
-			return {};
-		}
-		template<class SP>
-		SteppedParamIgnore stepped(const char *key, SP &param) {
-			int v = param;
-			(*this)(key, v);
-			param = v;
-			return {};
-		}
-		template<class V>
-		bool changed(const char *key, V &v) {
-			V prev = v;
-			(*this)(key, v);
-			return v == prev;
-		}
-		void invalidate(const char *) {}
-	};
 
 	std::vector<unsigned char> stateBuffer;
 	static bool state_save(const clap_plugin *obj, const clap_ostream *stream) {
 		auto &plugin = *(Plugin *)obj;
 		auto &buffer = plugin.stateBuffer;
-		StateWriter storage{buffer};
-		plugin.effect.state(storage);
+		plugin.effect.saveState(buffer);
 		return writeToStream(buffer.data(), buffer.size(), stream);
 	}
 	static bool state_load(const clap_plugin *obj, const clap_istream *stream) {
 		auto &plugin = *(Plugin *)obj;
 		auto &buffer = plugin.stateBuffer;
 		if (!fillFromStream(stream, buffer)) return false;
-		StateReader storage{buffer};
-		plugin.effect.state(storage);
-		
+		plugin.effect.loadState(buffer);
 		plugin.sendWebMessages(); // should already be on the main thread
 		return true;
 	}

stfx/storage/stfx-storage.h

@@ -0,0 +1,136 @@
+#pragma once
+
+#include "./storage.h"
+
+namespace stfx { namespace storage {
+
+template<class SubClassCRTP>
+struct STFXStorageScanner : public signalsmith::storage::StorageScanner<SubClassCRTP> {
+	void info(const char *, const char *) {}
+	int version(int v) {
+		return v;
+	}
+
+	template<class V>
+	bool changed(const char *key, V &v) {
+		auto &sub = *(SubClassCRTP *)this;
+		sub(key, v);
+		return false;
+	}
+	void invalidate(const char *) {}
+
+	bool extra() {
+		return false;
+	}
+	template<class V>
+	void extra(const char *, V) {}
+
+	template<class PR>
+	RangeParamIgnore range(const char *key, PR &param) {
+		return {};
+	}
+	template<class PS>
+	SteppedParamIgnore stepped(const char *key, PS &param) {
+		return {};
+	}
+};
+
+template<class SubClassCRTP=void>
+struct STFXStorageWriter : public signalsmith::storage::StorageCborWriter<SubClassCRTP> {
+	using signalsmith::storage::StorageCborWriter<SubClassCRTP>::StorageCborWriter;
+
+	void info(const char *name, const char *desc) {
+		sub().extra("name", name);
+		sub().extra("desc", desc);
+	}
+
+	template<class V>
+	bool changed(const char *key, V &v) {
+		sub()(key, v);
+		return false;
+	}
+	void invalidate(const char *) {}
+
+	int version(int v) {
+		sub()("version", v);
+		return v;
+	}
+	bool extra() {
+		return false;
+	}
+	template<class V>
+	void extra(const char *key, V v) {}
+
+	template<class PR>
+	RangeParamIgnore range(const char *key, PR &param) {
+		sub()(key, param);
+		return {};
+	}
+	template<class PS>
+	SteppedParamIgnore stepped(const char *key, PS &param) {
+		sub()(key, param);
+		return {};
+	}
+
+private:
+	SubClassCRTP & sub() {
+		return *(SubClassCRTP *)this;
+	}
+};
+
+template<class SubClassCRTP=void>
+struct STFXStorageReader : public signalsmith::storage::StorageCborReader<SubClassCRTP> {
+	using signalsmith::storage::StorageCborReader<SubClassCRTP>::StorageCborReader;
+
+	// This is supplemental
+	void info(const char *, const char *) {}
+
+	int version(int v) {
+		sub()("version", v);
+		return v;
+	}
+	bool extra() {
+		return false;
+	}
+	template<class V>
+	void extra(const char *key, V v) {}
+
+	template<class V>
+	bool changed(const char *key, V &v) {
+		V prev = v;
+		sub()(key, v);
+		return v != prev;
+	}
+	void invalidate(const char *invalidatedKey) {
+		LOG_EXPR(invalidatedKey);
+		abort();
+	}
+
+	template<class PR>
+	RangeParamIgnore range(const char *key, PR &param) {
+		sub()(key, param);
+		return {};
+	}
+	template<class PS>
+	SteppedParamIgnore stepped(const char *key, PS &param) {
+		sub()(key, param);
+		return {};
+	}
+
+private:
+	SubClassCRTP & sub() {
+		return *(SubClassCRTP *)this;
+	}
+};
+
+// If void, use itself for CRTP
+template<>
+struct STFXStorageWriter<void> : public STFXStorageWriter<STFXStorageWriter<void>> {
+	using STFXStorageWriter<STFXStorageWriter<void>>::STFXStorageWriter;
+};
+template<>
+struct STFXStorageReader<void> : public STFXStorageReader<STFXStorageReader<void>> {
+	using STFXStorageReader<STFXStorageReader<void>>::STFXStorageReader;
+};
+
+}} // namespace

stfx/storage/storage.h

@@ -2,14 +2,18 @@
 
 #include "./cbor-walker.h"
 
-namespace stfx { namespace storage {
+#include <string>
+#include <vector>
+
+namespace signalsmith { namespace storage {
 
 struct StorageDummy {
 	template<class V>
 	void operator()(const char *, V &) {}
 };
 
-struct StorageExample {
+template<class SubClassCRTP>
+struct StorageScanner {
 	template<class V>
 	void operator()(const char */*key*/, V &v) {
 		value(v);
@@ -27,6 +31,7 @@ private:
 	void value(float &v) {};
 	void value(double &v) {};
 	void value(bool &v) {};
+	void value(std::string &str) {};
 
 	template<class Item>
 	void value(std::vector<Item> &array) {
@@ -37,32 +42,16 @@ private:
 
 	template<class V>
 	void value(V &v) {
-		v.state(*this);
+		v.state(*(SubClassCRTP *)this);
 	}
 };
 
-namespace _impl {
-	template<class Fallback, class MaybeVoid=void>
-	struct VoidFallback {
-		using T = MaybeVoid;
-	};
-	template<class Fallback>
-	struct VoidFallback<Fallback, void> {
-		using T = Fallback;
-	};
-}
-
-template<bool compact=false, class SubClassCRTP=void>
+template<class SubClassCRTP=void>
 struct StorageCborWriter {
 	StorageCborWriter(const signalsmith::cbor::CborWriter &writer, std::vector<unsigned char> *buffer=nullptr) : cbor(writer) {
 		if (buffer) buffer->resize(0);
-		
-		if (compact) {
-			cbor.addTag(0xCB68ADED); // turns into "2store..." when base64-encoded
-			cbor.openArray();
-		} else {
-			cbor.openMap();
-		}
+
+		cbor.openMap();
 	}
 	StorageCborWriter(std::vector<unsigned char> &cborBuffer) : StorageCborWriter(signalsmith::cbor::CborWriter(cborBuffer), &cborBuffer) {}
 	~StorageCborWriter() {
@@ -71,7 +60,7 @@ struct StorageCborWriter {
 
 	template<class V>
 	void operator()(const char *key, V &value) {
-		if (!compact) cbor.addUtf8(key);
+		cbor.addUtf8(key);
 		writeValue(value);
 	}
 
@@ -102,6 +91,7 @@ private:
 		cbor.addBool(value);
 	}
 
+	// Support writing C strings (but not reading them), so inherited writers can add supplemental hints/info without allocating
 	void writeValue(const char *cStr) {
 		cbor.addUtf8(cStr);
 	}
@@ -133,26 +123,20 @@ private:
 	STORAGE_TYPED_ARRAY(double)
 #undef STORAGE_TYPED_ARRAY
 
-	using SubStorage = typename _impl::VoidFallback<StorageCborWriter, SubClassCRTP>::T;
-
 	template<class Obj>
 	void writeValue(Obj &obj) {
 		cbor.openMap();
-		obj.state(*(SubStorage *)this);
+		obj.state(*(SubClassCRTP *)this);
 		cbor.close();
 	}
 };
 
-template<bool compact=false, class SubClassCRTP=void>
+template<class SubClassCRTP=void>
 struct StorageCborReader {
 	using Cbor = signalsmith::cbor::TaggedCborWalker;
 	
 	StorageCborReader(Cbor c) : cbor(c) {
-		if (compact) {
-			if (cbor.isArray()) cbor = cbor.enter();
-		} else {
-			if (cbor.isMap()) cbor = cbor.enter();
-		}
+		if (cbor.isMap()) cbor = cbor.enter();
 	}
 	StorageCborReader(const std::vector<unsigned char> &v) : StorageCborReader(Cbor(v)) {}
 	
@@ -160,13 +144,13 @@ struct StorageCborReader {
 	void operator()(const char *key, V &v) {
 		if (filterKeyBytes != nullptr) {
 			if (!keyMatch(key, filterKeyBytes, filterKeyLength)) return;
-		} else if (!compact) {
-			if (!cbor.isUtf8()) return; // We expect a string key
-			if (!keyMatch(key, (const char *)cbor.bytes(), cbor.length())) {
-				return; // key doesn't match
-			}
-			cbor++;
 		}
+		if (!cbor.isUtf8()) return; // We expect a string key
+		// If we have a filter, we *should* be just in front of the appropriate key, but check anyway
+		if (!keyMatch(key, (const char *)cbor.bytes(), cbor.length())) {
+			return; // key doesn't match
+		}
+		cbor++;
 		readValue(v);
 	}
 
@@ -177,11 +161,6 @@ private:
 
 	template<class Obj>
 	void readValue(Obj &obj) {
-		if (compact) {
-			// No keys, no filters
-			return obj.state(*(SubClass *)this);
-		}
-		
 		if (!cbor.isMap()) return;
 
 		cbor = cbor.forEachPair([&](Cbor key, Cbor value){
@@ -193,8 +172,8 @@ private:
 			// Temporarily set key, and scan the object for that property
 			filterKeyBytes = (const char *)key.bytes();
 			filterKeyLength = key.length();
-			cbor = value;
-			obj.state(*(SubClass *)this);
+			cbor = key;
+			obj.state(*(SubClassCRTP *)this);
 
 			filterKeyBytes = fkb;
 			filterKeyLength = fkl;
@@ -219,7 +198,9 @@ private:
 #undef STORAGE_BASIC_TYPE
 
 	void readValue(std::string &v) {
-		v = (cbor++).utf8();
+		if (!cbor.isUtf8()) v.clear();
+		v.assign((const char *)cbor.bytes(), cbor.length());
+		++cbor;
 	}
 	
 	template<class Item>
@@ -263,8 +244,16 @@ private:
 		}
 		return key[filterKeyLength] == 0;
 	}
-	
-	using SubClass = typename _impl::VoidFallback<StorageCborReader, SubClassCRTP>::T;
+};
+
+// If void, use itself for CRTP
+template<>
+struct StorageCborWriter<void> : public StorageCborWriter<StorageCborWriter<void>> {
+	using StorageCborWriter<StorageCborWriter<void>>::StorageCborWriter;
+};
+template<>
+struct StorageCborReader<void> : public StorageCborReader<StorageCborReader<void>> {
+	using StorageCborReader<StorageCborReader<void>>::StorageCborReader;
 };
 
 }} // namespace

stfx/ui/html/generic.html

@@ -9,7 +9,7 @@
 			body {
 				display: grid;
 				grid-template-areas: "header" "params";
-				grid-template-rows: 3em 1fr;
+				grid-template-rows: min-content 1fr;
 				
 				margin: 0;
 				padding: 0;
@@ -113,7 +113,6 @@
 							data.gesture = true;
 							data._gestureUnit = data.rangeUnit;
 							if (count == 2) {
-								console.log("data.gesture", data.gesture);
 								data.value = data.defaultValue;
 								data.gesture = false;
 							}

stfx/ui/web-ui.h

@@ -21,80 +21,40 @@ struct ParamContext {
 	ParamContext() : index(0) {}
 };
 
-struct WebStateWriter : public storage::StorageCborWriter<false, WebStateWriter> {
-	using Super = storage::StorageCborWriter<false, WebStateWriter>;
+struct WebStateWriter : public storage::STFXStorageWriter<WebStateWriter> {
+	using Super = storage::STFXStorageWriter<WebStateWriter>;
 
 	using Super::Super;
-	
-	void info(const char *name, const char *desc) {
-		extra("name", name);
-		extra("desc", desc);
-	}
-	
-	int version(int v) {
-		return v; // we don't use old states, so not worth tracking
-	}
-	
+
+	// There should never be a version mismatch, ignore this
+	int version(int v) {return v;}
+
+	// Include extra info
 	bool extra() {
 		return true;
 	}
-	
 	template<class V>
 	void extra(const char *key, V v) {
 		(*this)(key, v);
 	}
-
-	template<class PR>
-	RangeParamIgnore range(const char *key, PR &param) {
-		(*this)(key, param);
-		return {};
-	}
-	template<class PS>
-	SteppedParamIgnore stepped(const char *key, PS &param) {
-		(*this)(key, param);
-		return {};
-	}
-	template<class V>
-	bool changed(const char *key, V &v) {
-		(*this)(key, v);
-		return false;
-	}
-	void invalidate(const char *) {}
 };
 
-struct WebStateReader : public storage::StorageCborReader<false, WebStateReader> {
-	using Super = storage::StorageCborReader<false, WebStateReader>;
+struct WebStateReader : public storage::STFXStorageReader<WebStateReader> {
+	using Super = storage::STFXStorageReader<WebStateReader>;
 
 	using Super::Super;
 	
-	void info(const char *, const char *) {}
-	
+	// There should never be a version mismatch, ignore this
 	int version(int v) {return v;}
 
+	// We're interested in an extended set of values being sent back
 	bool extra() {
-		// We're interested in an extended set of values being sent back, even if we ignore actual "extra" things
 		return true;
 	}
-	
+	// But anything read-only gets skipped
 	template<class V>
 	void extra(const char *key, V v) {}
 
-	template<class PR>
-	RangeParamIgnore range(const char *key, PR &param) {
-		(*this)(key, param);
-		return {};
-	}
-	template<class PS>
-	SteppedParamIgnore stepped(const char *key, PS &param) {
-		(*this)(key, param);
-		return {};
-	}
-	template<class V>
-	bool changed(const char *key, V &v) {
-		V prev = v;
-		(*this)(key, v);
-		return v != prev;
-	}
 	void invalidate(const char *invalidatedKey) {
 		LOG_EXPR(invalidatedKey);
 	}
@@ -334,6 +294,16 @@ struct WebUIHelper {
 		std::function<void(ParamContext, double)> paramListenerRange;
 		std::function<void(ParamContext, bool)> paramListenerGesture;
 		std::function<void(ParamContext, int)> paramListenerStepped;
+		
+		void saveState(std::vector<unsigned char> &bytes) {
+			stfx::storage::STFXStorageWriter<> storage(bytes);
+			this->state(storage);
+		}
+		void loadState(const std::vector<unsigned char> &bytes) {
+			stfx::storage::STFXStorageReader<> storage(bytes);
+			this->state(storage);
+			requestEntireState();
+		}
 
 		struct WebMessage {
 			std::vector<unsigned char> bytes;