Merge pull request #2744 from Akeit0/optimize-parser

Optimize Glb parser

Packages/UniGLTF/Runtime/UniGLTF/IO/GltfData.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.InteropServices;
+using UniJSON;
 using Unity.Collections;
 
 namespace UniGLTF
@@ -32,7 +33,7 @@ namespace UniGLTF
         /// JSON chunk ToString
         /// > This chunk MUST be the very first chunk of Binary glTF asset
         /// </summary>
-        public string Json { get; }
+        public string Json => _jsonString ??= _utf8JsonString.ToString();
 
         /// <summary>
         /// GLTF parsed from JSON chunk
@@ -72,10 +73,39 @@ namespace UniGLTF
         /// <returns></returns>
         Dictionary<string, NativeArray<byte>> _UriCache = new Dictionary<string, NativeArray<byte>>();
 
+        /// <summary>
+        /// json string in utf8
+        /// </summary>
+        Utf8String _utf8JsonString;
+
+        /// <summary>
+        /// json string cache
+        /// </summary>
+        string _jsonString;
+
         public GltfData(string targetPath, string json, glTF gltf, IReadOnlyList<GlbChunk> chunks, IStorage storage, MigrationFlags migrationFlags)
         {
             TargetPath = targetPath;
-            Json = json;
+            _jsonString = json;
+            GLTF = gltf;
+            Chunks = chunks;
+            _storage = storage;
+            MigrationFlags = migrationFlags;
+
+            // init
+            if (Chunks != null)
+            {
+                if (Chunks.Count >= 2)
+                {
+                    Bin = NativeArrayManager.CreateNativeArray(Chunks[1].Bytes);
+                }
+            }
+        }
+        
+        internal GltfData(string targetPath, Utf8String jsonString, glTF gltf, IReadOnlyList<GlbChunk> chunks, IStorage storage, MigrationFlags migrationFlags)
+        {
+            TargetPath = targetPath;
+            _utf8JsonString = jsonString;
             GLTF = gltf;
             Chunks = chunks;
             _storage = storage;
@@ -441,4 +471,4 @@ namespace UniGLTF
             return false;
         }
     }
-}
+}

Packages/UniGLTF/Runtime/UniGLTF/IO/Parser/GlbLowLevelParser.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Text;
 using System.Text.RegularExpressions;
 using UniJSON;
 
@@ -33,7 +32,7 @@ namespace UniGLTF
                 var jsonBytes = chunks[0].Bytes;
                 return ParseGltf(
                     _path,
-                    Encoding.UTF8.GetString(jsonBytes.Array, jsonBytes.Offset, jsonBytes.Count),
+                    new Utf8String(new ArraySegment<byte>(jsonBytes.Array, jsonBytes.Offset, jsonBytes.Count)),
                     chunks,
                     default,
                     new MigrationFlags()
@@ -73,14 +72,20 @@ namespace UniGLTF
 
         public static GltfData ParseGltf(string path, string json, IReadOnlyList<GlbChunk> chunks, IStorage storage, MigrationFlags migrationFlags)
         {
-            var GLTF = GltfDeserializer.Deserialize(json.ParseAsJson());
+            return ParseGltf(path, Utf8String.From(json), chunks, storage, migrationFlags);
+        }
+
+        internal static GltfData ParseGltf(string path, Utf8String json, IReadOnlyList<GlbChunk> chunks, IStorage storage, MigrationFlags migrationFlags)
+        {
+            var parsedJson = json.ParseAsJson();
+            var GLTF = GltfDeserializer.Deserialize(parsedJson);
             if (GLTF.asset.version != "2.0")
             {
                 throw new UniGLTFException("unknown gltf version {0}", GLTF.asset.version);
             }
 
             // Version Compatibility
-            RestoreOlderVersionValues(json, GLTF);
+            RestoreOlderVersionValues(parsedJson, GLTF);
 
             FixMeshNameUnique(GLTF);
             FixBlendShapeNameUnique(GLTF);
@@ -298,9 +303,8 @@ namespace UniGLTF
             }
         }
 
-        private static void RestoreOlderVersionValues(string Json, glTF GLTF)
+        private static void RestoreOlderVersionValues(JsonNode parsed, glTF GLTF)
         {
-            var parsed = UniJSON.JsonParser.Parse(Json);
             for (int i = 0; i < GLTF.images.Count; ++i)
             {
                 if (string.IsNullOrEmpty(GLTF.images[i].name))

Packages/UniGLTF/Runtime/UniJSON/Json/JsonString.cs

@@ -395,6 +395,28 @@ namespace UniJSON
             return writeCount;
         }
 
+        private static Utf8String Unescape(Utf8String s)
+        {
+            var span  = s.AsSpan();
+            var escapeIndex = span.IndexOf((byte)'\\');
+            
+            // escape not found
+            if (escapeIndex == -1)
+            {
+                return s;
+            }
+
+            var sb = new BytesStore(s.ByteLength);
+            foreach (var b in span[..escapeIndex])
+            {
+                sb.Write(b);
+            }
+
+            Unescape(s.Subbytes(escapeIndex), sb);
+            return new Utf8String(sb.Bytes);
+        }
+        
+
         public static string Unescape(string src)
         {
             var sb = new StringBuilder();
@@ -430,18 +452,9 @@ namespace UniJSON
 
         public static Utf8String Unquote(Utf8String src)
         {
-            var count = Unquote(src, null);
+            return Unescape(src.Subbytes(1, src.ByteLength - 2));
-            if (count == src.ByteLength - 2)
-            {
-                return src.Subbytes(1, src.ByteLength - 2);
-            }
-            else
-            {
-                var sb = new BytesStore(count);
-                Unquote(src, sb);
-                return new Utf8String(sb.Bytes);
-            }
         }
+
         #endregion
     }
-}
+}

Packages/UniGLTF/Runtime/UniJSON/Json/JsonValue.cs

@@ -101,7 +101,7 @@ namespace UniJSON
         public UInt64 GetUInt64() { return Segment.ToUInt64(); }
         public Single GetSingle() { return Segment.ToSingle(); }
         public Double GetDouble() { return Segment.ToDouble(); }
-        public String GetString() { return JsonString.Unquote(Segment.ToString()); }
+        public String GetString() { return JsonString.Unquote(Segment).ToString(); }
         public Utf8String GetUtf8String() { return JsonString.Unquote(Segment); }
     }
-}
+}

Packages/UniGLTF/Runtime/UniJSON/Utf8String/Utf8String.cs

@@ -110,6 +110,8 @@ namespace UniJSON
             return new Utf8String(bytes);
         }
 
+        public ReadOnlySpan<byte> AsSpan() => Bytes.AsSpan();
+
         public override string ToString()
         {
             if (ByteLength == 0) return "";
@@ -324,4 +326,4 @@ namespace UniJSON
             }
         }
     }
-}
+}

Packages/UniGLTF/Runtime/UniJSON/Utf8String/Utf8StringExtensions.cs

@@ -1,5 +1,7 @@
 using System;
+using System.Buffers;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 
 
@@ -320,11 +322,46 @@ namespace UniJSON
 
         public static float ToSingle(this Utf8String src)
         {
-            return Single.Parse(src.ToAscii(), System.Globalization.CultureInfo.InvariantCulture);
+            char[] arrayToReturn = null;
+            try
+            {
+                var srcBytes = src.AsSpan();
+                Span<char> chars = srcBytes.Length < 64
+                    ? stackalloc char[srcBytes.Length]
+                    : arrayToReturn = ArrayPool<char>.Shared.Rent(srcBytes.Length);
+                var count = System.Text.Encoding.ASCII.GetChars(srcBytes, chars);
+                return Single.Parse(chars[..count], NumberStyles.Float | NumberStyles.AllowThousands,
+                    System.Globalization.CultureInfo.InvariantCulture);
+            }
+            finally
+            {
+                if (arrayToReturn != null)
+                {
+                    ArrayPool<char>.Shared.Return(arrayToReturn);
+                }
+            }
         }
+
         public static double ToDouble(this Utf8String src)
         {
-            return Double.Parse(src.ToAscii(), System.Globalization.CultureInfo.InvariantCulture);
+            char[] arrayToReturn = null;
+            try
+            {
+                var srcBytes = src.AsSpan();
+                Span<char> chars = srcBytes.Length < 64
+                    ? stackalloc char[srcBytes.Length]
+                    : arrayToReturn = ArrayPool<char>.Shared.Rent(srcBytes.Length);
+                var count = System.Text.Encoding.ASCII.GetChars(srcBytes, chars);
+                return Double.Parse(chars[..count], NumberStyles.Float | NumberStyles.AllowThousands,
+                    System.Globalization.CultureInfo.InvariantCulture);
+            }
+            finally
+            {
+                if (arrayToReturn != null)
+                {
+                    ArrayPool<char>.Shared.Return(arrayToReturn);
+                }
+            }
         }
 
         public static Utf8String GetLine(this Utf8String src)