Added Resource Manager

src/Engine/Core/ResourceManager.cpp

@@ -0,0 +1,118 @@
+#include "PrecompiledHeader.h"
+#include "Core/ResourceManager.h"
+
+std::unordered_map<std::string, std::string> ResourceManager::m_CompilerTypenameToResourceType;
+std::unordered_map<std::string, std::function<Resource*(std::string)>> ResourceManager::m_FactoryFunctions;
+std::unordered_map<std::pair<std::string, std::string>, Resource*> ResourceManager::m_ResourceCache;
+std::unordered_map<std::string, Resource*> ResourceManager::m_ResourceFromName;
+std::unordered_map<Resource*, Resource*> ResourceManager::m_ResourceParents;
+unsigned int ResourceManager::m_CurrentResourceTypeID = 0;
+std::unordered_map<std::string, unsigned int> ResourceManager::m_ResourceTypeIDs;
+std::unordered_map<unsigned int, unsigned int> ResourceManager::m_ResourceCount;
+bool ResourceManager::m_Preloading = false;
+FileWatcher ResourceManager::m_FileWatcher;
+
+unsigned int ResourceManager::GetTypeID(std::string resourceType)
+{
+	if (m_ResourceTypeIDs.find(resourceType) == m_ResourceTypeIDs.end()) {
+		m_ResourceTypeIDs[resourceType] = m_CurrentResourceTypeID++;
+	}
+	return m_ResourceTypeIDs[resourceType];
+}
+
+
+void ResourceManager::Reload(std::string resourceName)
+{
+	auto it = m_ResourceFromName.find(resourceName);
+	if (it != m_ResourceFromName.end()) {
+		LOG_INFO("Reloading resource \"%s\"", resourceName.c_str());
+		Resource* resource = it->second;
+		resource->Reload();
+
+		// Notify parent
+		auto it2 = m_ResourceParents.find(resource);
+		if (it2 != m_ResourceParents.end()) {
+			it2->second->OnChildReloaded(resource);
+		}
+	}
+}
+
+unsigned int ResourceManager::GetNewResourceID(unsigned int typeID)
+{
+	return m_ResourceCount[typeID]++;
+}
+
+bool ResourceManager::IsResourceLoaded(std::string resourceType, std::string resourceName)
+{
+	return m_ResourceCache.find(std::make_pair(resourceType, resourceName)) != m_ResourceCache.end();
+}
+
+void ResourceManager::fileWatcherCallback(std::string path, FileWatcher::FileEventFlags flags)
+{
+	if (flags & FileWatcher::FileEventFlags::SizeChanged || flags & FileWatcher::FileEventFlags::TimestampChanged) {
+		auto it = m_ResourceFromName.find(path);
+		if (it != m_ResourceFromName.end()) {
+			Reload(path);
+		}
+	}
+}
+
+void ResourceManager::Update()
+{
+	m_FileWatcher.Check();
+}
+
+void ResourceManager::Preload(std::string resourceType, std::string resourceName)
+{
+	if (IsResourceLoaded(resourceType, resourceName)) {
+		//LOG_WARNING("Attempted to preload resource \"%s\" multiple times!", resourceName.c_str());
+		return;
+	}
+
+	m_Preloading = true;
+	LOG_INFO("Preloading resource \"%s\"", resourceName.c_str());
+	CreateResource(resourceType, resourceName, nullptr);
+	m_Preloading = false;
+}
+
+Resource* ResourceManager::Load(std::string resourceType, std::string resourceName, Resource* parent /*= nullptr*/)
+{
+	auto it = m_ResourceCache.find(std::make_pair(resourceType, resourceName));
+	if (it != m_ResourceCache.end()) {
+		return it->second;
+	}
+
+	if (m_Preloading) {
+		LOG_INFO("Preloading resource \"%s\"", resourceName.c_str());
+	} else {
+		LOG_WARNING("Hot-loading resource \"%s\"", resourceName.c_str());
+	}
+
+	return CreateResource(resourceType, resourceName, parent);
+}
+
+Resource* ResourceManager::CreateResource(std::string resourceType, std::string resourceName, Resource* parent)
+{
+	auto facIt = m_FactoryFunctions.find(resourceType);
+	if (facIt == m_FactoryFunctions.end()) {
+		LOG_ERROR("Failed to load resource \"%s\" of type \"%s\": type not registered", resourceName.c_str(), resourceType.c_str());
+		return nullptr;
+	}
+
+	// Call the factory function
+	Resource* resource = facIt->second(resourceName);
+	// Store IDs
+	resource->TypeID = GetTypeID(resourceType);
+	resource->ResourceID = GetNewResourceID(resource->TypeID);
+	// Cache
+	m_ResourceCache[std::make_pair(resourceType, resourceName)] = resource;
+	m_ResourceFromName[resourceName] = resource;
+	if (parent != nullptr) {
+		m_ResourceParents[resource] = parent;
+	}
+	if (!boost::filesystem::is_directory(resourceName)) {
+		LOG_DEBUG("Adding watch for %s", resourceName.c_str());
+		m_FileWatcher.AddWatch(resourceName, fileWatcherCallback);
+	}
+	return resource;
+}