usp10: Refine post-matra Ralf reordering to be post below form consonants as well.

dlls/usp10/indic.c

@@ -238,6 +238,7 @@ static BOOL Consonent_is_ralf(HDC hdc, SCRIPT_ANALYSIS *psa, ScriptCache* psc, L
 static int FindBaseConsonant(HDC hdc, SCRIPT_ANALYSIS *psa, ScriptCache* psc, LPWSTR input, IndicSyllable *s, lexical_function lex)
 {
     int i;
+    BOOL blwf = FALSE;
 
     /* remove ralf from consideration */
     if (Consonent_is_ralf(hdc, psa, psc, input, s, lex))
@@ -257,8 +258,10 @@ static int FindBaseConsonant(HDC hdc, SCRIPT_ANALYSIS *psa, ScriptCache* psc, LP
             }
     }
 
-    while (Consonent_is_below_base_form(hdc, psa, psc, input, s, lex) || Consonent_is_post_base_form(hdc, psa, psc, input, s, lex) || Consonent_is_pre_base_form(hdc, psa, psc, input, s, lex))
+    while ((blwf = Consonent_is_below_base_form(hdc, psa, psc, input, s, lex)) || Consonent_is_post_base_form(hdc, psa, psc, input, s, lex) || Consonent_is_pre_base_form(hdc, psa, psc, input, s, lex))
     {
+        if (blwf && s->blwf == -1)
+            s->blwf = s->base - 1;
         for (i = s->base-1; i >= s->start; i--)
             if (is_consonant( lex(input[i]) ))
             {
@@ -270,6 +273,9 @@ static int FindBaseConsonant(HDC hdc, SCRIPT_ANALYSIS *psa, ScriptCache* psc, LP
     if (s->ralf >= 0)
         s->start = s->ralf;
 
+    if (s->ralf == s->base)
+        s->ralf = -1;
+
     return s->base;
 }
 
@@ -303,6 +309,7 @@ void Indic_ReorderCharacters( HDC hdc, SCRIPT_ANALYSIS *psa, ScriptCache* psc, L
             (*syllables)[*syllable_count].start = index;
             (*syllables)[*syllable_count].base = center;
             (*syllables)[*syllable_count].ralf = -1;
+            (*syllables)[*syllable_count].blwf = -1;
             (*syllables)[*syllable_count].end = next-1;
             FindBaseConsonant(hdc, psa, psc, input, &(*syllables)[*syllable_count], lex);
             reorder_f(input, &(*syllables)[*syllable_count], lex);

dlls/usp10/shape.c

@@ -1767,9 +1767,10 @@ static void Reorder_Ra_follows_matra(LPWSTR pwChar, IndicSyllable *s, lexical_fu
     if (s->ralf >= 0)
     {
         int j,loc;
+        int stop = (s->blwf >=0)? s->blwf+1 : s->base;
         WORD Ra = pwChar[s->start];
         WORD H = pwChar[s->start+1];
-        for (loc = s->end; loc > s->base; loc--)
+        for (loc = s->end; loc > stop; loc--)
             if (lexical(pwChar[loc]) == lex_Matra_post || lexical(pwChar[loc]) == lex_Matra_below)
                 break;
 
@@ -1781,6 +1782,7 @@ static void Reorder_Ra_follows_matra(LPWSTR pwChar, IndicSyllable *s, lexical_fu
 
         s->ralf = loc-1;
         s->base -= 2;
+        if (s->blwf >= 0) s->blwf -= 2;
     }
 }
 
@@ -1800,6 +1802,7 @@ static void Reorder_Ra_follows_syllable(LPWSTR pwChar, IndicSyllable *s, lexical
 
         s->ralf = s->end-1;
         s->base -= 2;
+        if (s->blwf >= 0) s->blwf -= 2;
     }
 }
 
@@ -1822,6 +1825,7 @@ static void Reorder_Matra_precede_base(LPWSTR pwChar, IndicSyllable *s, lexical_
                 pwChar[s->base] = c;
 
                 if (s->ralf >= s->base) s->ralf++;
+                if (s->blwf >= s->base) s->blwf++;
                 s->base ++;
             }
         }
@@ -1847,6 +1851,7 @@ static void Reorder_Matra_precede_syllable(LPWSTR pwChar, IndicSyllable *s, lexi
                 pwChar[s->start] = c;
 
                 if (s->ralf >= 0) s->ralf++;
+                if (s->blwf >= 0) s->blwf++;
                 s->base ++;
             }
         }
@@ -1916,6 +1921,8 @@ static inline void shift_syllable_glyph_indexs(IndicSyllable *glyph_index, INT i
         glyph_index->end+= shift;
     if (glyph_index->ralf > index)
         glyph_index->ralf+= shift;
+    if (glyph_index->blwf > index)
+        glyph_index->blwf+= shift;
 }
 
 static void Apply_Indic_BasicForm(HDC hdc, ScriptCache *psc, SCRIPT_ANALYSIS *psa, WCHAR* pwChars, INT cChars, IndicSyllable *syllable, WORD *pwOutGlyphs, INT* pcGlyphs, WORD *pwLogClust, lexical_function lexical, IndicSyllable *glyph_index, const GSUB_Feature *feature )
@@ -2014,7 +2021,10 @@ static void Apply_Indic_PostBase(HDC hdc, ScriptCache *psc, SCRIPT_ANALYSIS *psa
 
     count = syllable->end - syllable->base;
 
-    g_offset = 0;
+    if (syllable->ralf >= syllable->base)
+        g_offset = -1;
+    else
+        g_offset = 0;
     index = find_halant_consonant(&pwChars[syllable->base], 0, count, lexical);
 
     while (index >= 0)

dlls/usp10/usp10_internal.h

@@ -100,6 +100,7 @@ typedef struct {
     INT start;
     INT base;
     INT ralf;
+    INT blwf;
     INT end;
 } IndicSyllable;