Start of asset management 2.0

2026-09-05 21:01:52 +00:00 · 2024-05-19 01:35:52 +02:00
parent 989ad4a5bd
commit 2725801db8
21 changed files with 2192 additions and 52 deletions
@@ -0,0 +1,157 @@
+using System;
+using GlitchyEngine;
+using System.IO;
+using System.Collections;
+using GlitchyEngine.Core;
+using GlitchyEngine.Content;
+
+namespace GlitchyEditor.Assets;
+
+/// Represents a processed asset file as it lies in the cache-directory.
+class CachedAsset
+{
+	public const char8[3] MagicWord = .('L', 'A', 'F');
+	
+	public String FilePath ~ delete _;
+
+	public uint16 FormatVersion;
+	public AssetHandle Handle;
+	public DateTime CreationTimestamp;
+	public AssetCompression Compression;
+	public AssetType AssetType;
+	public int64 CompressedByteCount;
+	public int64 UncompressedByteCount;
+	public String AssetIdentifier ~ delete _;
+
+	public const String CacheFileExtension = ".laf";
+}
+
+/// Manages the cache for already processed assets
+class AssetCache
+{
+	/// Current format version of loose asset file (.laf) file reader and writer.
+	public const uint16 FormatVersion = 1;
+
+	private append String _directory = .() ~ delete:append _;
+
+	private append Dictionary<AssetHandle, CachedAsset> _assets ~ delete:append _;
+
+	public StringView CacheDirectory => _directory;
+
+	private bool _cacheLoaded;
+
+	public ~this()
+	{
+		ClearCache();
+	}
+
+	private void ClearCache()
+	{
+		_cacheLoaded = false;
+		ClearDictionaryAndDeleteValues!(_assets);
+	}
+
+	/// Sets the directory in which the processed assets are cached.
+	public void SetDirectory(StringView directory)
+	{
+		_directory.Set(directory);
+		ReloadCache();
+	}
+
+	// TODO: This might take ages for large projects and definitely shouldn't run in the main thread!
+	public void ReloadCache()
+	{
+		ClearCache();
+
+		if (!Directory.Exists(_directory))
+		{
+			Log.EngineLogger.Info($"Asset cache directory doesn't exist, creating directory \"{_directory}\"...");
+
+			if (Directory.CreateDirectory(_directory) case .Err(let error))
+			{
+				Log.EngineLogger.Critical($"Failed to create cache directory \"{_directory}\". Reason: {error}.");
+				Log.EngineLogger.Critical($"The engine will not function properly without the asset cache directory. Save your project and restart the engine.");
+			}
+
+			// At this point we either just created the cache directory and thus it's empty,
+			// or we failed and can't do anything anyway.
+			return;
+		}
+		
+		String filePath = scope .();
+		for (FileFindEntry file in Directory.EnumerateFiles(_directory))
+		{
+			filePath.Clear();
+			file.GetFilePath(filePath);
+
+			if (!filePath.EndsWith(CachedAsset.CacheFileExtension, .OrdinalIgnoreCase))
+				continue;
+			
+			CachedAsset cachedAsset = new .();
+			if (ReadAssetFile(filePath, cachedAsset) case .Err)
+			{
+				Log.EngineLogger.Error($"Failed to read cached asset file \"filePath\".");
+
+				delete cachedAsset;
+			}
+
+			_assets.Add(cachedAsset.Handle, cachedAsset);
+		}
+
+		_cacheLoaded = true;
+	}
+
+	private Result<void> ReadAssetFile(StringView filePath, CachedAsset cachedAsset)
+	{
+		cachedAsset.FilePath = new String(filePath);
+
+		FileStream stream = scope .();
+		Try!(stream.Open(filePath));
+
+		// Check magic word
+		char8[3] magicWord = Try!(stream.Read<char8[3]>());
+		if (magicWord != CachedAsset.MagicWord)
+			return .Err;
+
+		cachedAsset.FormatVersion = Try!(stream.Read<uint16>());
+
+		// Validate format version
+		if (cachedAsset.FormatVersion == 0 || cachedAsset.FormatVersion > FormatVersion)
+		{
+			Log.EngineLogger.Error("The cached assets version is either invalid or too new.");
+			return .Err;
+		}
+
+		cachedAsset.Handle = Try!(stream.Read<AssetHandle>());
+		cachedAsset.CreationTimestamp = Try!(stream.Read<DateTime>());
+		cachedAsset.Compression = Try!(stream.Read<AssetCompression>());
+		cachedAsset.AssetType = Try!(stream.Read<AssetType>());
+		cachedAsset.CompressedByteCount = Try!(stream.Read<int64>());
+		cachedAsset.UncompressedByteCount = Try!(stream.Read<int64>());
+
+		int32 assetIdentifierByteCount = Try!(stream.Read<int32>());
+
+		cachedAsset.AssetIdentifier = new String(assetIdentifierByteCount);
+		cachedAsset.AssetIdentifier.PadLeft(assetIdentifierByteCount);
+		Span<char8> charSpan = cachedAsset.AssetIdentifier;
+		int readBytes = Try!(stream.TryRead(Span<uint8>((uint8*)charSpan.Ptr, charSpan.Length)));
+
+		if (readBytes != assetIdentifierByteCount)
+		{
+			Log.EngineLogger.Warning($"Expected to read {assetIdentifierByteCount} bytes for the asset identifier, but read {readBytes} instead.");
+		}
+
+		return .Ok;
+	}
+
+	public CachedAsset GetCacheEntry(AssetHandle id)
+	{
+		if (!_cacheLoaded)
+			ReloadCache();
+
+		if (_assets.TryGetValue(id, let cachedAsset))
+			return cachedAsset;
+
+		return null;
+	}
+}