wire up cidtogid map for type2cid fonts

src/UglyToad.PdfPig/Fonts/CidFonts/CharacterIdentifierToGlyphIndexMap.cs

@@ -0,0 +1,49 @@
+namespace UglyToad.PdfPig.Fonts.CidFonts
+{
+    /// <summary>
+    /// Specifies mapping from character identifiers to glyph indices.
+    /// Can either be defined as a name in which case it must be Identity or a stream which defines the mapping.
+    /// </summary>
+    internal class CharacterIdentifierToGlyphIndexMap
+    {
+        private readonly bool isIdentity;
+        private readonly int[] map;
+
+        public CharacterIdentifierToGlyphIndexMap()
+        {
+            isIdentity = true;
+            map = null;
+        }
+
+        public CharacterIdentifierToGlyphIndexMap(byte[] streamBytes)
+        {
+            var numberOfEntries = streamBytes.Length / 2;
+
+            map = new int[numberOfEntries];
+            var offset = 0;
+
+            for (var i = 0; i < numberOfEntries; i++)
+            {
+                var glyphIndex = (streamBytes[offset] << 8) | streamBytes[offset + 1];
+                map[i] = glyphIndex;
+
+                offset += 2;
+            }
+        }
+
+        public int GetGlyphIndex(int characterIdentifier)
+        {
+            if (isIdentity)
+            {
+                return characterIdentifier;
+            }
+
+            if (characterIdentifier >= map.Length || characterIdentifier < 0)
+            {
+                return 0;
+            }
+
+            return map[characterIdentifier];
+        }
+    }
+}

src/UglyToad.PdfPig/Fonts/CidFonts/ICidFont.cs

@@ -42,6 +42,6 @@
 
         decimal GetWidthFromDictionary(int cid);
 
-        PdfRectangle GetBoundingBox(int characterCode);
+        PdfRectangle GetBoundingBox(int characterIdentifier);
     }
 }

src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs

@@ -1,5 +1,6 @@
 namespace UglyToad.PdfPig.Fonts.CidFonts
 {
+    using System;
     using Geometry;
 
     /// <summary>
@@ -8,5 +9,6 @@
     internal interface ICidFontProgram
     {
         bool TryGetBoundingBox(int characterCode, out PdfRectangle boundingBox);
+        bool TryGetBoundingBox(int characterCode, Func<int, int> characterIdentifierToGlyphIndex, out PdfRectangle boundingBox);
     }
 }

src/UglyToad.PdfPig/Fonts/CidFonts/Type0CidFont.cs

@@ -34,7 +34,7 @@
             throw new System.NotImplementedException();
         }
 
-        public PdfRectangle GetBoundingBox(int characterCode)
+        public PdfRectangle GetBoundingBox(int characterIdentifier)
         {
             throw new System.NotImplementedException();
         }

src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs

@@ -15,6 +15,7 @@
         private readonly ICidFontProgram fontProgram;
         private readonly VerticalWritingMetrics verticalWritingMetrics;
         private readonly IReadOnlyDictionary<int, decimal> widths;
+        private readonly CharacterIdentifierToGlyphIndexMap cidToGid;
 
         public NameToken Type { get; }
         public NameToken SubType { get; }
@@ -24,10 +25,11 @@
         public CidFontType CidFontType => CidFontType.Type2;
         public FontDescriptor Descriptor { get; }
 
-        public Type2CidFont(NameToken type, NameToken subType, NameToken baseFont, CharacterIdentifierSystemInfo systemInfo, 
+        public Type2CidFont(NameToken type, NameToken subType, NameToken baseFont, CharacterIdentifierSystemInfo systemInfo,
             FontDescriptor descriptor, ICidFontProgram fontProgram,
             VerticalWritingMetrics verticalWritingMetrics,
-            IReadOnlyDictionary<int, decimal> widths)
+            IReadOnlyDictionary<int, decimal> widths, 
+            CharacterIdentifierToGlyphIndexMap cidToGid)
         {
             Type = type;
             SubType = subType;
@@ -37,6 +39,7 @@
             this.fontProgram = fontProgram;
             this.verticalWritingMetrics = verticalWritingMetrics;
             this.widths = widths;
+            this.cidToGid = cidToGid;
 
             // TODO: This should maybe take units per em into account?
             var scale = 1 / 1000m;
@@ -49,9 +52,9 @@
             throw new System.NotImplementedException();
         }
 
-        public decimal GetWidthFromDictionary(int cid)
+        public decimal GetWidthFromDictionary(int characterIdentifier)
         {
-            if (widths.TryGetValue(cid, out var width))
+            if (widths.TryGetValue(characterIdentifier, out var width))
             {
                 return width;
             }
@@ -59,14 +62,14 @@
             return Descriptor.MissingWidth;
         }
 
-        public PdfRectangle GetBoundingBox(int characterCode)
+        public PdfRectangle GetBoundingBox(int characterIdentifier)
         {
             if (fontProgram == null)
             {
                 return Descriptor.BoundingBox;
             }
 
-            if (fontProgram.TryGetBoundingBox(characterCode, out var result))
+            if (fontProgram.TryGetBoundingBox(characterIdentifier, cidToGid.GetGlyphIndex, out var result))
             {
                 return result;
             }

src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs

@@ -90,7 +90,9 @@
 
         public PdfRectangle GetBoundingBox(int characterCode)
         {
-            return CidFont.GetBoundingBox(characterCode);
+            var cid = CMap.ConvertToCid(characterCode);
+
+            return CidFont.GetBoundingBox(cid);
         }
 
         public TransformationMatrix GetFontMatrix()

src/UglyToad.PdfPig/Fonts/Parser/Parts/CidFontFactory.cs

@@ -52,7 +52,7 @@
             var baseFont = dictionary.GetNameOrDefault(NameToken.BaseFont);
 
             var systemInfo = GetSystemInfo(dictionary);
-
+            
             var subType = dictionary.GetNameOrDefault(NameToken.Subtype);
             if (NameToken.CidFontType0.Equals(subType))
             {
@@ -61,12 +61,14 @@
 
             if (NameToken.CidFontType2.Equals(subType))
             {
-                return new Type2CidFont(type, subType, baseFont, systemInfo, descriptor, fontProgram, verticalWritingMetrics, widths);
+                var cidToGid = GetCharacterIdentifierToGlyphIndexMap(dictionary, isLenientParsing);
+
+                return new Type2CidFont(type, subType, baseFont, systemInfo, descriptor, fontProgram, verticalWritingMetrics, widths, cidToGid);
             }
 
             return null;
         }
-
+        
         private bool TryGetFontDescriptor(DictionaryToken dictionary, out DictionaryToken descriptorDictionary)
         {
             descriptorDictionary = null;
@@ -152,7 +154,7 @@
             return widths;
         }
 
-        private VerticalWritingMetrics ReadVerticalDisplacements(DictionaryToken dict)
+        private static VerticalWritingMetrics ReadVerticalDisplacements(DictionaryToken dict)
         {
             var verticalDisplacements = new Dictionary<int, decimal>();
             var positionVectors = new Dictionary<int, PdfVector>();
@@ -237,6 +239,30 @@
             return new CharacterIdentifierSystemInfo(registry, ordering, supplement);
         }
 
+        private CharacterIdentifierToGlyphIndexMap GetCharacterIdentifierToGlyphIndexMap(DictionaryToken dictionary, bool isLenientParsing)
+        {
+            if (!dictionary.TryGet(NameToken.CidToGidMap, out var entry))
+            {
+                return new CharacterIdentifierToGlyphIndexMap();
+            }
+
+            if (entry is NameToken name)
+            {
+                if (!name.Equals(NameToken.CidToGidMap) && !isLenientParsing)
+                {
+                    throw new InvalidOperationException($"The CIDToGIDMap in a Type 0 font should have the value /Identity, instead got: {name}.");
+                }
+
+                return new CharacterIdentifierToGlyphIndexMap();
+            }
+
+            var stream = DirectObjectFinder.Get<StreamToken>(entry, pdfScanner);
+
+            var bytes = stream.Decode(filterProvider);
+
+            return new CharacterIdentifierToGlyphIndexMap(bytes);
+        }
+
         private string SafeKeyAccess(DictionaryToken dictionary, NameToken keyName)
         {
             if (!dictionary.TryGet(keyName, out var token))

src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs

@@ -31,16 +31,23 @@
             GlyphTable = tableRegister.GlyphDataTable;
         }
 
-        public bool TryGetBoundingBox(int characterCode, out PdfRectangle boundingBox)
+        public bool TryGetBoundingBox(int characterCode, out PdfRectangle boundingBox) => TryGetBoundingBox(characterCode, null, out boundingBox);
+        public bool TryGetBoundingBox(int characterCode, Func<int, int> characterIdentifierToGlyphIndex, out PdfRectangle boundingBox)
         {
             boundingBox = default(PdfRectangle);
 
+            int index;
+
             if (CMapTable == null)
             {
-                return false;
-            }
+                if (characterIdentifierToGlyphIndex == null)
+                {
+                    return false;
+                }
 
-            if (!CMapTable.TryGetGlyphIndex(characterCode, out var index))
+                index = characterIdentifierToGlyphIndex(characterCode);
+            }
+            else if (!CMapTable.TryGetGlyphIndex(characterCode, out index))
             {
                 return false;
             }