From 8d591ca913ebb67fd8be623de7240992c9498f2f Mon Sep 17 00:00:00 2001
From: Eliot Jones <elioty@hotmail.co.uk>
Date: Mon, 16 Apr 2018 23:58:27 +0100
Subject: [PATCH] fix bounding boxes for type 0 truetype fonts

---
 src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs  | 2 ++
 src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs     | 2 +-
 src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs       | 8 +++++---
 src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs | 2 +-
 src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs     | 5 +++++
 5 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs b/src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs
index 739f586c..23b7ab5f 100644
--- a/src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs
+++ b/src/UglyToad.PdfPig/Fonts/CidFonts/ICidFontProgram.cs
@@ -13,5 +13,7 @@
         bool TryGetBoundingBox(int characterCode, Func<int, int> characterIdentifierToGlyphIndex, out PdfRectangle boundingBox);
 
         bool TryGetBoundingAdvancedWidth(int characterCode, out decimal width);
+
+        int GetFontMatrixMultiplier();
     }
 }
diff --git a/src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs b/src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs
index 7211dc8f..fe693300 100644
--- a/src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs
+++ b/src/UglyToad.PdfPig/Fonts/CidFonts/Type2CidFont.cs
@@ -42,7 +42,7 @@
             this.cidToGid = cidToGid;
 
             // TODO: This should maybe take units per em into account?
-            var scale = 1 / 1000m;
+            var scale = 1 / (decimal)(fontProgram?.GetFontMatrixMultiplier() ?? 1000);
             FontMatrix = TransformationMatrix.FromValues(scale, 0, 0, scale, 0, 0);
         }
 
diff --git a/src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs b/src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs
index 3702d8a8..c36dd898 100644
--- a/src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs
+++ b/src/UglyToad.PdfPig/Fonts/Composite/Type0Font.cs
@@ -30,8 +30,6 @@
 
         public bool IsVertical => CMap.WritingMode == WritingMode.Vertical;
 
-        private readonly TransformationMatrix fontMatrix = TransformationMatrix.FromValues(0.001m, 0, 0, 0.001m, 0, 0);
-
         public Type0Font(NameToken baseFont, ICidFont cidFont, CMap cmap, CMap toUnicodeCMap)
         {
             BaseFont = baseFont ?? throw new ArgumentNullException(nameof(baseFont));
@@ -73,7 +71,11 @@
 
         public PdfRectangle GetBoundingBox(int characterCode)
         {
-            return fontMatrix.Transform(GetBoundingBoxInGlyphSpace(characterCode));
+            var matrix = GetFontMatrix();
+
+            var boundingBox = GetBoundingBoxInGlyphSpace(characterCode);
+
+            return matrix.Transform(boundingBox);
         }
 
         public decimal GetWidth(int characterCode)
diff --git a/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs b/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
index 74c07cc9..48e9f9cc 100644
--- a/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
+++ b/src/UglyToad.PdfPig/Fonts/Simple/TrueTypeSimpleFont.cs
@@ -137,7 +137,7 @@ namespace UglyToad.PdfPig.Fonts.Simple
 
             if (font?.HeaderTable != null)
             {
-                scale = font.HeaderTable.UnitsPerEm;
+                scale = font.GetFontMatrixMultiplier();
             }
 
             return TransformationMatrix.FromValues(1m / scale, 0, 0, 1m / scale, 0, 0);
diff --git a/src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs b/src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs
index 8c06ecab..f6de8d3f 100644
--- a/src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs
+++ b/src/UglyToad.PdfPig/Fonts/TrueType/TrueTypeFont.cs
@@ -69,6 +69,11 @@
             return TryGetBoundingAdvancedWidthByIndex(index, out width);
         }
 
+        public int GetFontMatrixMultiplier()
+        {
+            return HeaderTable?.UnitsPerEm ?? 1000;
+        }
+
         private bool TryGetBoundingAdvancedWidthByIndex(int index, out decimal width)
         {
             width = TableRegister.HorizontalMetricsTable.GetAdvanceWidth(index);