move getting the bounding box from a truetype font to the cid font program interface so it can be used from the type 0 and truetype font. comment the pfb parsing logic in type1 fonts

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

@@ -1,6 +1,7 @@
 namespace UglyToad.PdfPig.Fonts.CidFonts
 {
     using Core;
+    using Geometry;
     using Tokenization.Tokens;
 
     /// <summary>
@@ -39,8 +40,8 @@
 
         FontDescriptor Descriptor { get; }
 
-        decimal GetWidthFromFont(int characterCode);
-
         decimal GetWidthFromDictionary(int cid);
+
+        PdfRectangle GetBoundingBox(int characterCode);
     }
 }

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

@@ -1,10 +1,12 @@
 namespace UglyToad.PdfPig.Fonts.CidFonts
 {
+    using Geometry;
+
     /// <summary>
     /// Represents either an Adobe Type 1 or TrueType font program for a CIDFont.
     /// </summary>
     internal interface ICidFontProgram
     {
-
+        bool TryGetBoundingBox(int characterCode, out PdfRectangle boundingBox);
     }
 }

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

@@ -1,6 +1,7 @@
 namespace UglyToad.PdfPig.Fonts.CidFonts
 {
     using Core;
+    using Geometry;
     using Tokenization.Tokens;
 
     /// <inheritdoc/>
@@ -32,5 +33,10 @@
         {
             throw new System.NotImplementedException();
         }
+
+        public PdfRectangle GetBoundingBox(int characterCode)
+        {
+            throw new System.NotImplementedException();
+        }
     }
 }

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

@@ -2,6 +2,7 @@
 {
     using System.Collections.Generic;
     using Core;
+    using Geometry;
     using Tokenization.Tokens;
 
     /// <inheritdoc />
@@ -57,5 +58,20 @@
 
             return Descriptor.MissingWidth;
         }
+
+        public PdfRectangle GetBoundingBox(int characterCode)
+        {
+            if (fontProgram == null)
+            {
+                return Descriptor.BoundingBox;
+            }
+
+            if (fontProgram.TryGetBoundingBox(characterCode, out var result))
+            {
+                return result;
+            }
+
+            return Descriptor.BoundingBox;
+        }
     }
 }

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

@@ -88,7 +88,7 @@
 
         public PdfRectangle GetBoundingBox(int characterCode)
         {
-            throw new NotImplementedException();
+            return CidFont.GetBoundingBox(characterCode);
         }
 
         public TransformationMatrix GetFontMatrix()

src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs

@@ -107,19 +107,17 @@
 
         public PdfRectangle GetBoundingBox(int characterCode)
         {
-            if (font?.CMapTable == null)
+            if (font == null)
             {
                 return descriptor.BoundingBox;
             }
 
-            if (!font.CMapTable.TryGetGlyphIndex(characterCode, out var index))
+            if (font.TryGetBoundingBox(characterCode, out var bounds))
             {
-                return descriptor.BoundingBox;
+                return bounds;
             }
 
-            var glyph = font.GlyphTable.Glyphs[index];
-
-            return glyph?.GlyphBounds ?? descriptor.BoundingBox;
+            return descriptor.BoundingBox;
         }
 
         public TransformationMatrix GetFontMatrix()

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

@@ -3,6 +3,7 @@
     using System;
     using System.Collections.Generic;
     using CidFonts;
+    using Geometry;
     using Parser;
     using Tables;
 
@@ -29,5 +30,31 @@
             CMapTable = tableRegister.CMapTable;
             GlyphTable = tableRegister.GlyphDataTable;
         }
+
+        public bool TryGetBoundingBox(int characterCode, out PdfRectangle boundingBox)
+        {
+            boundingBox = default(PdfRectangle);
+
+            if (CMapTable == null)
+            {
+                return false;
+            }
+
+            if (!CMapTable.TryGetGlyphIndex(characterCode, out var index))
+            {
+                return false;
+            }
+
+            var glyph = GlyphTable.Glyphs[index];
+
+            if (glyph?.GlyphBounds == null)
+            {
+                return false;
+            }
+
+            boundingBox = glyph.GlyphBounds;
+
+            return true;
+        }
     }
 }

src/UglyToad.PdfPig/Fonts/Type1/Parser/Type1FontParser.cs

@@ -31,6 +31,7 @@
         /// <returns>The parsed type 1 font.</returns>
         public Type1Font Parse(IInputBytes inputBytes, int length1, int length2)
         {
+            // Sometimes the entire PFB file including the header bytes can be included which prevents parsing in the normal way.
             var isEntirePfbFile = inputBytes.Peek() == PfbFileIndicator;
 
             IReadOnlyList<byte> eexecPortion = new byte[0];
@@ -155,6 +156,14 @@
         /// </summary>
         private static (byte[] ascii, byte[] binary) ReadPfbHeader(IInputBytes bytes)
         {
+            /*
+             * The header is a 6 byte sequence. The first byte is 0x80 followed by 0x01 for the ASCII record indicator.
+             * The following 4 bytes determine the size/length of the ASCII part of the PFB file.
+             * After the ASCII part another 6 byte sequence is present, this time 0x80 0x02 for the Binary part length.
+             * A 3rd sequence is present at the end re-stating the ASCII length but this is surplus to requirements.
+             */
+
+            // ReSharper disable once ParameterOnlyUsedForPreconditionCheck.Local
             int ReadSize(byte recordType)
             {
                 bytes.MoveNext();