Add additional scripts in font mapping

This is an implementation of bug 8565810: Enable more complex scripts
in text layout

This change adds a number of additional scripts to the mapping from
"representative" Unicode code point to script tag, which is used by
Skia's fallback mechanism to find an appropriate font for a run of
text. In cases where Harfbuzz old does not have the script in its
enum (for legacy rendering), we use a value which can never occur,
which will preserve the existing behavior.

Change-Id: I3e197abf7a6ccf305d2e6409b17a8aeb7dc7d32e

1 files changed, 36 insertions, 26 deletions

diff --git a/src/ports/SkFontHost_android.cpp b/src/ports/SkFontHost_android.cpp
index 6dd9cab4e6..aeb819a6fa 100644
--- a/src/ports/SkFontHost_android.cpp
+++ b/src/ports/SkFontHost_android.cpp
@@ -1122,33 +1122,43 @@ struct HB_UnicodeMapping {
  * HB_SCRIPT_INHERITED
  */
 
+/* Harfbuzz (old) is missing a number of scripts in its table. For these,
+ * we include a value which can never happen. We won't get complex script
+ * shaping in these cases, but the library wouldn't know how to shape
+ * them anyway. */
+#define HB_Script_Unknown HB_ScriptCount
+
 static HB_UnicodeMapping HB_UnicodeMappingArray[] = {
-    {HB_Script_Armenian, HB_SCRIPT_ARMENIAN,      0x0531},
-    {HB_Script_Hebrew, HB_SCRIPT_HEBREW,        0x0591},
-    {HB_Script_Arabic, HB_SCRIPT_ARABIC,        0x0600},
-    {HB_Script_Syriac, HB_SCRIPT_SYRIAC,        0x0710},
-    {HB_Script_Thaana, HB_SCRIPT_THAANA,        0x0780},
-    {HB_Script_Nko, HB_SCRIPT_NKO,           0x07C0},
-    {HB_Script_Devanagari, HB_SCRIPT_DEVANAGARI,    0x0901},
-    {HB_Script_Bengali, HB_SCRIPT_BENGALI,       0x0981},
-    {HB_Script_Gurmukhi, HB_SCRIPT_GURMUKHI,      0x0A10},
-    {HB_Script_Gujarati, HB_SCRIPT_GUJARATI,      0x0A90},
-    {HB_Script_Oriya, HB_SCRIPT_ORIYA,         0x0B10},
-    {HB_Script_Tamil, HB_SCRIPT_TAMIL,         0x0B82},
-    {HB_Script_Telugu, HB_SCRIPT_TELUGU,        0x0C10},
-    {HB_Script_Kannada, HB_SCRIPT_KANNADA,       0x0C90},
-    {HB_Script_Malayalam, HB_SCRIPT_MALAYALAM,     0x0D10},
-    {HB_Script_Sinhala, HB_SCRIPT_SINHALA,       0x0D90},
-    {HB_Script_Thai, HB_SCRIPT_THAI,          0x0E01},
-    {HB_Script_Lao, HB_SCRIPT_LAO,           0x0E81},
-    {HB_Script_Tibetan, HB_SCRIPT_TIBETAN,       0x0F00},
-    {HB_Script_Myanmar, HB_SCRIPT_MYANMAR,       0x1000},
-    {HB_Script_Georgian, HB_SCRIPT_GEORGIAN,      0x10A0},
-    // we don't currently support HB_Script_Ethiopic, it is a placeholder for an upstream merge
-    //{HB_Script_Ethiopic, HB_SCRIPT_ETHIOPIC,    0x1200},
-    {HB_Script_Ogham, HB_SCRIPT_OGHAM,         0x1680},
-    {HB_Script_Runic, HB_SCRIPT_RUNIC,         0x16A0},
-    {HB_Script_Khmer, HB_SCRIPT_KHMER,         0x1780},
+    {HB_Script_Armenian,   HB_SCRIPT_ARMENIAN,    0x0531},
+    {HB_Script_Hebrew,     HB_SCRIPT_HEBREW,      0x0591},
+    {HB_Script_Arabic,     HB_SCRIPT_ARABIC,      0x0600},
+    {HB_Script_Syriac,     HB_SCRIPT_SYRIAC,      0x0710},
+    {HB_Script_Thaana,     HB_SCRIPT_THAANA,      0x0780},
+    {HB_Script_Nko,        HB_SCRIPT_NKO,         0x07C0},
+    {HB_Script_Devanagari, HB_SCRIPT_DEVANAGARI,  0x0901},
+    {HB_Script_Bengali,    HB_SCRIPT_BENGALI,     0x0981},
+    {HB_Script_Gurmukhi,   HB_SCRIPT_GURMUKHI,    0x0A10},
+    {HB_Script_Gujarati,   HB_SCRIPT_GUJARATI,    0x0A90},
+    {HB_Script_Oriya,      HB_SCRIPT_ORIYA,       0x0B10},
+    {HB_Script_Tamil,      HB_SCRIPT_TAMIL,       0x0B82},
+    {HB_Script_Telugu,     HB_SCRIPT_TELUGU,      0x0C10},
+    {HB_Script_Kannada,    HB_SCRIPT_KANNADA,     0x0C90},
+    {HB_Script_Malayalam,  HB_SCRIPT_MALAYALAM,   0x0D10},
+    {HB_Script_Sinhala,    HB_SCRIPT_SINHALA,     0x0D90},
+    {HB_Script_Thai,       HB_SCRIPT_THAI,        0x0E01},
+    {HB_Script_Lao,        HB_SCRIPT_LAO,         0x0E81},
+    {HB_Script_Tibetan,    HB_SCRIPT_TIBETAN,     0x0F00},
+    {HB_Script_Myanmar,    HB_SCRIPT_MYANMAR,     0x1000},
+    {HB_Script_Georgian,   HB_SCRIPT_GEORGIAN,    0x10A0},
+    {HB_Script_Unknown,    HB_SCRIPT_ETHIOPIC,    0x1200},
+    {HB_Script_Unknown,    HB_SCRIPT_CHEROKEE,    0x13A0},
+    {HB_Script_Ogham,      HB_SCRIPT_OGHAM,       0x1680},
+    {HB_Script_Runic,      HB_SCRIPT_RUNIC,       0x16A0},
+    {HB_Script_Khmer,      HB_SCRIPT_KHMER,       0x1780},
+    {HB_Script_Unknown,    HB_SCRIPT_TAI_LE,      0x1950},
+    {HB_Script_Unknown,    HB_SCRIPT_NEW_TAI_LUE, 0x1980},
+    {HB_Script_Unknown,    HB_SCRIPT_TAI_THAM,    0x1A20},
+    {HB_Script_Unknown,    HB_SCRIPT_CHAM,        0xAA00},
 };
 
 static hb_script_t getHBScriptFromHBScriptOld(HB_Script script_old) {