From 82353179281e4d53455e2d35b8e6c346626349cc Mon Sep 17 00:00:00 2001
From: Doug Felt <dougfelt@gmail.com>
Date: Mon, 21 Mar 2011 20:48:42 +0000
Subject: [PATCH] ICU-8318 disable hebrew ligatures, add symbolic constants for
 typo flags

X-SVN-Rev: 29676
---
 icu4c/source/layout/LayoutEngine.cpp | 13 +++++++++----
 icu4c/source/layout/LayoutEngine.h   | 22 ++++++++++++----------
 2 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/icu4c/source/layout/LayoutEngine.cpp b/icu4c/source/layout/LayoutEngine.cpp
index c13a08eb362..c815c83c855 100644
--- a/icu4c/source/layout/LayoutEngine.cpp
+++ b/icu4c/source/layout/LayoutEngine.cpp
@@ -1,8 +1,5 @@
-
 /*
- *
- * (C) Copyright IBM Corp. 1998-2009 - All Rights Reserved
- *
+ * (C) Copyright IBM Corp. 1998-2011 - All Rights Reserved
  */
 
 #include "LETypes.h"
@@ -38,6 +35,9 @@ U_NAMESPACE_BEGIN
 /* Leave this copyright notice here! It needs to go somewhere in this library. */
 static const char copyright[] = U_COPYRIGHT_STRING;
 
+const le_int32 LayoutEngine::kTypoFlagKern = 0x1;
+const le_int32 LayoutEngine::kTypoFlagLiga = 0x2;
+
 const LEUnicode32 DefaultCharMapper::controlChars[] = {
     0x0009, 0x000A, 0x000D,
     /*0x200C, 0x200D,*/ 0x200E, 0x200F,
@@ -554,6 +554,11 @@ LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstan
             result = new ArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
             break;
 
+        case hebrScriptCode:
+            // Disable hebrew ligatures since they have only archaic uses, see ticket #8318
+            result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags & ~kTypoFlagLiga, gsubTable, success);
+            break;
+
         case hangScriptCode:
             result = new HangulOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
             break;
diff --git a/icu4c/source/layout/LayoutEngine.h b/icu4c/source/layout/LayoutEngine.h
index b109e64e74d..2cb81584243 100644
--- a/icu4c/source/layout/LayoutEngine.h
+++ b/icu4c/source/layout/LayoutEngine.h
@@ -1,8 +1,5 @@
-
 /*
- *
- * (C) Copyright IBM Corp. 1998-2008 - All Rights Reserved
- *
+ * (C) Copyright IBM Corp. 1998-2011 - All Rights Reserved
  */
 
 #ifndef __LAYOUTENGINE_H
@@ -65,6 +62,12 @@ class LEGlyphStorage;
  * @stable ICU 2.8
  */
 class U_LAYOUT_API LayoutEngine : public UObject {
+public:
+    /** Flag to request kerning. */
+    static const le_int32 kTypoFlagKern;
+    /** Flag to request ligatures. */
+    static const le_int32 kTypoFlagLiga;
+
 protected:
     /**
      * The object which holds the glyph storage
@@ -122,8 +125,8 @@ protected:
      * @param fontInstance - the font for the text
      * @param scriptCode - the script for the text
      * @param languageCode - the language for the text
-     * @param typoFlags - the typographic control flags for the text.  Set bit 1 if kerning
-     * is desired, set bit 2 if ligature formation is desired.  Others are reserved.
+     * @param typoFlags - the typographic control flags for the text (a bitfield).  Use kTypoFlagKern
+     * if kerning is desired, kTypoFlagLiga if ligature formation is desired.  Others are reserved.
      * @param success - set to an error code if the operation fails
      *
      * @see LEFontInstance
@@ -131,9 +134,9 @@ protected:
      *
      * @internal
      */
-    LayoutEngine(const LEFontInstance *fontInstance, 
-                 le_int32 scriptCode, 
-                 le_int32 languageCode, 
+    LayoutEngine(const LEFontInstance *fontInstance,
+                 le_int32 scriptCode,
+                 le_int32 languageCode,
                  le_int32 typoFlags,
                  LEErrorCode &success);
 
@@ -493,4 +496,3 @@ public:
 
 U_NAMESPACE_END
 #endif
-