wip

Author: swmal

src/EPPlus.Fonts.OpenType.Tests/FontMeasurerPerformanceTest.cs

@@ -36,9 +36,8 @@ public class FontMeasurerPerformanceTest : FontTestBase
         /// Performance test for text wrapping. 
         /// Fixed kerning pairs major bottle-neck.
         /// </summary>
-        [TestMethod]
-        //[TestMethod, Ignore("This test should not run in a multithreaded test run. If we want to keep it, it should be moved to a separate benchmark project.")]
-        //[TestCategory("Benchmark")]
+        [TestMethod, Ignore("This test should not run in a multithreaded test run. If we want to keep it, it should be moved to a separate benchmark project.")]
+        [TestCategory("Benchmark")]
         public void Wrap20Paragraphs100Times()
         {
             List<string> longTexts = new List<string>();

src/EPPlus.Fonts.OpenType.Tests/FontTestBase.cs

@@ -112,7 +112,7 @@ protected static void DeleteOutputFont(string fileName)
         [TestInitialize]
         public void ClearAllCaches()
         {
-            OpenTypeFonts.ClearFontCache();
+            //OpenTypeFonts.ClearFontCache();
         }
 
         [ClassInitialize(InheritanceBehavior.BeforeEachDerivedClass)]

src/EPPlus.Fonts.OpenType.Tests/TextShaping/MarkToBaseTests.cs

@@ -17,7 +17,13 @@ public class MarkToBaseTests : FontTestBase
         [TestMethod]
         public void MarkToBaseTest()
         {
-            var font = OpenTypeFonts.GetFontData(null, "Roboto", FontSubFamily.Regular, true);
+            var font = OpenTypeFonts.GetFontData(null, "Roboto", FontSubFamily.Regular, true, true);
+            Debug.WriteLine("=== MarkToBaseTest ===");
+            Debug.WriteLine($"Font instance: {font.GetHashCode()}");
+            Debug.WriteLine($"CmapTable instance: {font.CmapTable.GetHashCode()}");
+            Debug.WriteLine($"SubTables count: {font.CmapTable.SubTables.Count}");
+            for (int i = 0; i < font.CmapTable.SubTables.Count; i++)
+                Debug.WriteLine($"  SubTable[{i}]: Format={font.CmapTable.SubTables[i].Format} HashCode={font.CmapTable.SubTables[i].GetHashCode()}");
             var shaper = new TextShaper(font);
 
             string test = "A\u0302\u0309";
@@ -31,6 +37,9 @@ public void MarkToBaseTest()
                     Debug.WriteLine($"GID={g.GlyphId,-4} XAdv={g.XAdvance,-5} YOff={g.YOffset,-4}");
                 }
 
+                Debug.WriteLine($"GPOS null? {font.GposTable == null}");
+                Debug.WriteLine($"FullyLoaded? {font.FullyLoaded}"); //
+
                 Assert.IsTrue(shaped.Glyphs.Any(x => x.YOffset > 0),
                     $"Expected YOffset > 0. Got: {string.Join(", ", shaped.Glyphs.Select(g => $"Y={g.YOffset}"))}");
             }

src/EPPlus.Fonts.OpenType/OpenTypeFont.cs

@@ -126,6 +126,55 @@ internal OpenTypeFont(byte[] fontBytes, long startOffset, FontFormat format)
 
         internal GlyfTableLoader _glyfTableLoader;
         internal KernTableLoader _kernTableLoader;
+        private volatile bool _fullyLoaded = false;
+
+        public bool FullyLoaded => _fullyLoaded;
+        internal bool IsReadOnly { get; set; }
+
+        internal void EnsureFullyLoaded()
+        {
+            if (_fullyLoaded)
+                return;
+
+            lock (_loaderCache.SyncLock)
+            {
+
+                // --- Required tables (always present in valid fonts) ---
+                // Each property accessor calls its TableLoader.Load() which
+                // reads from the byte[] stream and caches the result.
+                // By accessing them all here under the font-level lock,
+                // we guarantee no concurrent reader access.
+                FontTableBase _ = CmapTable;
+                _ = HeadTable;
+                _ = HheaTable;
+                _ = HmtxTable;
+                _ = MaxpTable;
+                _ = NameTable;
+                _ = Os2Table;
+                _ = PostTable;
+                _ = LocaTable;
+
+                // --- Optional tables (only if present in font) ---
+                if (_gsubTableLoader != null)
+                {
+                    var gsub = GsubTable;  // Forces full GSUB parse
+                }
+                if (_gposTableLoader != null)
+                {
+                    var gpos = GposTable;  // Forces full GPOS parse (incl. MarkToBase subtables)
+                }
+                if (_glyfTableLoader != null)
+                {
+                    var glyf = GlyfTable;  // Forces full glyph outline parse
+                }
+                if (_kernTableLoader != null)
+                {
+                    var kern = KernTable;  // Forces legacy kern table parse
+                }
+
+                _fullyLoaded = true;
+            }
+        }
 
         internal FontSerializationContext GetSerializationContext()
         {
@@ -488,6 +537,10 @@ private string GetNameString(NameRecordTypes recordType)
         internal void AddOrReplaceTable<T>(T table)
             where T : FontTableBase
         {
+            if (IsReadOnly)
+                throw new InvalidOperationException(
+                    $"Cannot modify a cached font instance. Table: {table.Name}. " +
+                    "Use CreateSubset() or create a new OpenTypeFont instance.");
             _localTableCache.AddOrReplace(table.Name, table);
 
 
@@ -509,25 +562,21 @@ internal void AddOrReplaceTable<T>(T table)
 
         public OpenTypeFont CreateSubset(IEnumerable<char> usedChars)
         {
-            // Validate input
             if (usedChars == null)
                 throw new ArgumentNullException(nameof(usedChars));
-
             var charArray = usedChars.ToArray();
             if (charArray.Length == 0)
                 throw new ArgumentException("Text cannot be empty", nameof(usedChars));
 
             var subsetBuilder = new SubsetFontBuilder();
-
-            // Convert chars to Unicode code points (handling surrogate pairs)
             var codePoints = CharacterUtil.ExtractCodePointsFromChars(charArray);
 
-            // Create subset font
+            // Använd "this" direkt — IsReadOnly-skyddet på AddOrReplaceTable 
+            // garanterar att denna instans aldrig modifieras av subsetting.
             var newFont = subsetBuilder.CreateSubset(this, codePoints);
 
             var postProcessor = new SubsetPostProcessor();
             postProcessor.PostProcessSubset(newFont);
-
             return newFont;
         }
 

src/EPPlus.Fonts.OpenType/OpenTypeFonts.cs

@@ -19,6 +19,7 @@ Date               Author                       Change
 using EPPlus.Fonts.OpenType.Utils.Platform;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
 using System.Linq;
 
@@ -150,6 +151,8 @@ public static OpenTypeFont GetFontDataOpen(
                     var cached = OpenTypeFontCache.GetFromCache(fontName, subFamily);
                     if (cached != null && cached.Font != null && cached.IsLoaded)
                     {
+                        cached.Font.EnsureFullyLoaded();
+                        Debug.WriteLine($"[CACHE HIT] {fontName}_{subFamily} → Font={cached.Font.GetHashCode()}, CmapSubTables={cached.Font.CmapTable?.SubTables?.Count}");
                         return cached.Font;
                     }
                 }
@@ -168,10 +171,12 @@ public static OpenTypeFont GetFontDataOpen(
 
                 // Load the font from file
                 var font = OpenTypeFontFactory.CreateFromFace(face);
+                font.EnsureFullyLoaded();
 
                 // Add to cache and signal waiting threads
                 if (!ignoreCache)
                 {
+                    font.IsReadOnly = true;
                     OpenTypeFontCache.AddToCache(font, fontName, subFamily);
                 }
 

src/EPPlus.Fonts.OpenType/TextShaping/TextShaper.cs

@@ -20,6 +20,7 @@ Date               Author                       Change
 using OfficeOpenXml.Interfaces.Drawing.Text;
 using System;
 using System.Collections.Generic;
+using static System.Net.Mime.MediaTypeNames;
 
 namespace EPPlus.Fonts.OpenType.TextShaping
 {
@@ -70,6 +71,8 @@ public TextShaper(IFontProvider fontProvider)
             if (fontProvider.PrimaryFont == null)
                 throw new ArgumentException("Primary font cannot be null in font provider", "fontProvider");
 
+            var gposTable = fontProvider.PrimaryFont.GposTable;  // Force load now - thread-safe via TableLoader
+
             _fontProvider = fontProvider;
             _primaryFont = fontProvider.PrimaryFont;