Hot reload

src/runtime/RuntimeLayerModel.cpp

@@ -8,6 +8,35 @@
 
 namespace RenderCadenceCompositor
 {
+namespace
+{
+JsonValue ParameterValueToJson(const ShaderParameterDefinition& definition, const ShaderParameterValue& value)
+{
+	switch (definition.type)
+	{
+	case ShaderParameterType::Float:
+		return JsonValue(value.numberValues.empty() ? 0.0 : value.numberValues.front());
+	case ShaderParameterType::Vec2:
+	case ShaderParameterType::Color:
+	{
+		JsonValue array = JsonValue::MakeArray();
+		for (double number : value.numberValues)
+			array.pushBack(JsonValue(number));
+		return array;
+	}
+	case ShaderParameterType::Boolean:
+		return JsonValue(value.booleanValue);
+	case ShaderParameterType::Enum:
+		return JsonValue(value.enumValue);
+	case ShaderParameterType::Text:
+		return JsonValue(value.textValue);
+	case ShaderParameterType::Trigger:
+		return JsonValue(value.numberValues.empty() ? 0.0 : value.numberValues.front());
+	}
+	return JsonValue();
+}
+}
+
 bool RuntimeLayerModel::InitializeSingleLayer(const SupportedShaderCatalog& shaderCatalog, const std::string& shaderId, std::string& error)
 {
 	Clear();
@@ -27,6 +56,7 @@ bool RuntimeLayerModel::InitializeSingleLayer(const SupportedShaderCatalog& shad
 	Layer layer;
 	layer.id = AllocateLayerId();
 	layer.shaderId = shaderPackage->id;
+	layer.packageFingerprint = ShaderPackageFingerprint(*shaderPackage);
 	layer.shaderName = shaderPackage->displayName.empty() ? shaderPackage->id : shaderPackage->displayName;
 	layer.buildState = RuntimeLayerBuildState::Pending;
 	layer.message = "Runtime Slang build is waiting to start.";
@@ -48,6 +78,7 @@ bool RuntimeLayerModel::AddLayer(const SupportedShaderCatalog& shaderCatalog, co
 	Layer layer;
 	layer.id = AllocateLayerId();
 	layer.shaderId = shaderPackage->id;
+	layer.packageFingerprint = ShaderPackageFingerprint(*shaderPackage);
 	layer.shaderName = shaderPackage->displayName.empty() ? shaderPackage->id : shaderPackage->displayName;
 	layer.buildState = RuntimeLayerBuildState::Pending;
 	layer.message = "Runtime Slang build is waiting to start.";
@@ -130,6 +161,7 @@ bool RuntimeLayerModel::SetLayerShader(const SupportedShaderCatalog& shaderCatal
 	}
 
 	layer->shaderId = shaderPackage->id;
+	layer->packageFingerprint = ShaderPackageFingerprint(*shaderPackage);
 	layer->shaderName = shaderPackage->displayName.empty() ? shaderPackage->id : shaderPackage->displayName;
 	layer->buildState = RuntimeLayerBuildState::Pending;
 	layer->message = "Runtime Slang build is waiting to start.";
@@ -195,6 +227,61 @@ bool RuntimeLayerModel::ResetParameters(const std::string& layerId, std::string&
 	return true;
 }
 
+bool RuntimeLayerModel::ReloadFromCatalog(const SupportedShaderCatalog& shaderCatalog, std::vector<std::pair<std::string, std::string>>& buildsToStart, std::string& error)
+{
+	buildsToStart.clear();
+	for (Layer& layer : mLayers)
+	{
+		const ShaderPackage* shaderPackage = shaderCatalog.FindPackage(layer.shaderId);
+		if (!shaderPackage)
+		{
+			layer.buildState = RuntimeLayerBuildState::Failed;
+			layer.message = "Shader '" + layer.shaderId + "' is no longer available after reload.";
+			continue;
+		}
+
+		const std::string nextFingerprint = ShaderPackageFingerprint(*shaderPackage);
+		if (layer.packageFingerprint == nextFingerprint)
+			continue;
+
+		std::map<std::string, ShaderParameterDefinition> previousDefinitions;
+		for (const ShaderParameterDefinition& definition : layer.parameterDefinitions)
+			previousDefinitions[definition.id] = definition;
+
+		std::map<std::string, ShaderParameterValue> nextValues;
+		for (const ShaderParameterDefinition& nextDefinition : shaderPackage->parameters)
+		{
+			const auto previousDefinitionIt = previousDefinitions.find(nextDefinition.id);
+			const auto previousValueIt = layer.parameterValues.find(nextDefinition.id);
+			if (previousDefinitionIt != previousDefinitions.end()
+				&& previousValueIt != layer.parameterValues.end()
+				&& previousDefinitionIt->second.type == nextDefinition.type)
+			{
+				ShaderParameterValue preservedValue;
+				JsonValue valueJson = ParameterValueToJson(previousDefinitionIt->second, previousValueIt->second);
+				std::string normalizeError;
+				if (NormalizeAndValidateParameterValue(nextDefinition, valueJson, preservedValue, normalizeError))
+				{
+					nextValues[nextDefinition.id] = preservedValue;
+					continue;
+				}
+			}
+			nextValues[nextDefinition.id] = DefaultValueForDefinition(nextDefinition);
+		}
+
+		layer.shaderName = shaderPackage->displayName.empty() ? shaderPackage->id : shaderPackage->displayName;
+		layer.packageFingerprint = nextFingerprint;
+		layer.parameterDefinitions = shaderPackage->parameters;
+		layer.parameterValues = std::move(nextValues);
+		if (layer.renderReady)
+			layer.artifact.parameterValues = layer.parameterValues;
+		buildsToStart.push_back({ layer.id, layer.shaderId });
+	}
+
+	error.clear();
+	return true;
+}
+
 void RuntimeLayerModel::Clear()
 {
 	mLayers.clear();
@@ -229,6 +316,7 @@ bool RuntimeLayerModel::MarkBuildReady(const RuntimeShaderArtifact& artifact, st
 	}
 
 	layer->shaderName = artifact.displayName.empty() ? artifact.shaderId : artifact.displayName;
+	layer->packageFingerprint = artifact.packageFingerprint;
 	layer->buildState = RuntimeLayerBuildState::Ready;
 	layer->message = artifact.message;
 	layer->renderReady = true;