diff --git a/tools/make_unicode b/tools/make_unicode
index 1acc424398f..cae3547b7a9 100755
--- a/tools/make_unicode
+++ b/tools/make_unicode
@@ -279,13 +279,8 @@ my %special_categories =
 my %directions =
 (
     "L"   => 1,    # Left-to-Right
-    "LRE" => 15,   # Left-to-Right Embedding
-    "LRO" => 15,   # Left-to-Right Override
     "R"   => 2,    # Right-to-Left
     "AL"  => 12,   # Right-to-Left Arabic
-    "RLE" => 15,   # Right-to-Left Embedding
-    "RLO" => 15,   # Right-to-Left Override
-    "PDF" => 15,   # Pop Directional Format
     "EN"  => 3,    # European Number
     "ES"  => 4,    # European Number Separator
     "ET"  => 5,    # European Number Terminator
@@ -296,7 +291,16 @@ my %directions =
     "B"   => 8,    # Paragraph Separator
     "S"   => 9,    # Segment Separator
     "WS"  => 10,   # Whitespace
-    "ON"  => 11    # Other Neutrals
+    "ON"  => 11,   # Other Neutrals
+    "LRE" => 15,   # Left-to-Right Embedding
+    "LRO" => 15,   # Left-to-Right Override
+    "RLE" => 15,   # Right-to-Left Embedding
+    "RLO" => 15,   # Right-to-Left Override
+    "PDF" => 15,   # Pop Directional Format
+    "LRI" => 15,   # Left-to-Right Isolate
+    "RLI" => 15,   # Right-to-Left Isolate
+    "FSI" => 15,   # First Strong Isolate
+    "PDI" => 15    # Pop Directional Isolate
 );
 
 my %joining_types =