Fix for bug 8695466 GPOS combining mark positioning broken before space
This patch makes segmentation into script runs behave the same in RTL
as in LTR modes - so that inherited script characters are always
associated with the preceding run. Otherwise, for a sequence such as
u+0631 u+064d u+0020, it would get split after the first character,
which would lose the ability to correctly position the u+064d mark.
Change-Id: I3c12ba1b77d18334f55e707f518be1046e6b339b
diff --git a/core/jni/android/graphics/TextLayoutCache.cpp b/core/jni/android/graphics/TextLayoutCache.cpp
index 17f205d..bcc1573 100644
--- a/core/jni/android/graphics/TextLayoutCache.cpp
+++ b/core/jni/android/graphics/TextLayoutCache.cpp
@@ -622,11 +622,11 @@
const hb_script_t init_script = code_point_to_script(init_cp);
hb_script_t current_script = init_script;
run->script = init_script;
+ size_t break_iter = *iter;
for (;;) {
if (*iter < 0)
break;
- const ssize_t prev_iter = *iter;
const uint32_t cp = utf16_to_code_point_prev(chars, len, iter);
const hb_script_t script = code_point_to_script(cp);
@@ -635,21 +635,18 @@
// If we started off as inherited, we take whatever we can find.
run->script = script;
current_script = script;
+ // In cases of script1 + inherited + script2, always group the inherited
+ // with script1.
+ break_iter = *iter;
continue;
} else if (script == HB_SCRIPT_INHERITED) {
- /* BEGIN android-changed
- We apply the same fix for Chrome to Android.
- Chrome team will talk with upsteam about it.
- Just assume that whatever follows this combining character is within
- the same script. This is incorrect if you had language1 + combining
- char + language 2, but that is rare and this code is suspicious
- anyway.
- END android-changed */
continue;
} else {
- *iter = prev_iter;
+ *iter = break_iter;
break;
}
+ } else {
+ break_iter = *iter;
}
}