diff --git a/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs b/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
index 9b5ace7f..22a454b0 100644
--- a/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
+++ b/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
@@ -12,6 +12,9 @@
 
     internal class TrueTypeSimpleFont : IFont
     {
+        private static readonly TransformationMatrix DefaultTransformation =
+            TransformationMatrix.FromValues(1m / 1000m, 0, 0, 1m / 1000m, 0, 0);
+
         private readonly FontDescriptor descriptor;
 
         [CanBeNull]
@@ -90,32 +93,51 @@
         {
             var fontMatrix = GetFontMatrix();
 
-            var boundingBox = GetBoundingBoxInGlyphSpace(characterCode);
+            var boundingBox = GetBoundingBoxInGlyphSpace(characterCode, out var fromFont);
 
-            boundingBox = fontMatrix.Transform(boundingBox);
+            var boundingBoxPreTransform = boundingBox.Width;
 
+            if (fromFont)
+            {
+                boundingBox = fontMatrix.Transform(boundingBox);
+            }
+            else
+            {
+                boundingBox = DefaultTransformation.Transform(boundingBox);
+            }
+            
             decimal width;
             if (font == null)
             {
+                fromFont = false;
                  width = widths[characterCode];
             }
             else
             {
                 if (!font.TryGetBoundingAdvancedWidth(characterCode, out width))
                 {
-                    width = boundingBox.Width;
+                    width = boundingBoxPreTransform;
                 }
             }
             
             var advancedRectangle = new PdfRectangle(0, 0, width, 0);
 
-            advancedRectangle = fontMatrix.Transform(advancedRectangle);
+            if (fromFont)
+            {
+                advancedRectangle = fontMatrix.Transform(advancedRectangle);
+            }
+            else
+            {
+                advancedRectangle = DefaultTransformation.Transform(advancedRectangle);
+            }
 
             return new CharacterBoundingBox(boundingBox, advancedRectangle);
         }
 
-        private PdfRectangle GetBoundingBoxInGlyphSpace(int characterCode)
+        private PdfRectangle GetBoundingBoxInGlyphSpace(int characterCode, out bool fromFont)
         {
+            fromFont = true;
+            
             if (font == null)
             {
                 return descriptor.BoundingBox;
@@ -131,6 +153,8 @@
                 return new PdfRectangle(0, 0, width, 0);
             }
 
+            fromFont = false;
+
             return new PdfRectangle(0, 0, GetWidth(characterCode), 0);
         }
 
diff --git a/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapSubTables/Format4CMapTable.cs b/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapSubTables/Format4CMapTable.cs
index 604a6df8..b08a6594 100644
--- a/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapSubTables/Format4CMapTable.cs
+++ b/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapSubTables/Format4CMapTable.cs
@@ -45,7 +45,7 @@ namespace UglyToad.PdfPig.Fonts.TrueType.Tables.CMapSubTables
 
                 if (segment.IdRangeOffset == 0)
                 {
-                    return (characterCode + segment.IdDelta) % ushort.MaxValue;
+                    return (characterCode + segment.IdDelta) & 0xFFFF;
                 }
 
                 var offset = segment.IdRangeOffset / 2 + (characterCode - segment.StartCode);
diff --git a/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapTable.cs b/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapTable.cs
index 9775074d..c0aa5a82 100644
--- a/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapTable.cs
+++ b/src/UglyToad.PdfPig/Fonts/TrueType/Tables/CMapTable.cs
@@ -30,6 +30,8 @@
                 return false;
             }
 
+            var windowsMapping = default(ICMapSubTable);
+
             foreach (var subTable in subTables)
             {
                 glyphIndex = subTable.CharacterCodeToGlyphIndex(characterCode);
@@ -38,6 +40,37 @@
                 {
                     return true;
                 }
+
+                if (subTable.EncodingId == 0 && subTable.PlatformId == 3)
+                {
+                    windowsMapping = subTable;
+                }
+            }
+
+            if (windowsMapping != null && characterCode >= 0 && characterCode <= 255)
+            {
+                // the CMap may use one of the following code ranges, so that we have to add the high byte to get the
+                // mapped value
+                glyphIndex = windowsMapping.CharacterCodeToGlyphIndex(characterCode + 0xF000);
+
+                if (glyphIndex != 0)
+                {
+                    return true;
+                }
+
+                glyphIndex = windowsMapping.CharacterCodeToGlyphIndex(characterCode + 0xF100);
+
+                if (glyphIndex != 0)
+                {
+                    return true;
+                }
+
+                glyphIndex = windowsMapping.CharacterCodeToGlyphIndex(characterCode + 0xF200);
+
+                if (glyphIndex != 0)
+                {
+                    return true;
+                }
             }
 
             return false;