Explicitly handle dangling upper/lower marks by optionally using

2004-10-09  Theppitak Karoonboonyanan  <thep@linux.thai.net>

	Explicitly handle dangling upper/lower marks by optionally using
	dottedcircle as base, rather than requiring it.

	* modules/thai/thai-shaper.h: Explicitly declare make_glyph and
	get_glyph functions for 8-bit and Unicode chars as separate functions.

	* modules/thai/thai-shaper.c (get_adjusted_glyphs_list): Rename
	function calls to the new ones. Conditionally use dottedcircle glyph
	as base for dangling upper/lower marks if available; simply expand
	width to that of inkrect otherwise.

	* modules/thai/thai-fc.c: Implement those new functions declared in
	thai-shaper.h. Remove 0x25cc from tis620_2 glyph set.

3 files changed, 122 insertions, 78 deletions

diff --git a/modules/thai/thai-fc.c b/modules/thai/thai-fc.c
index ac4c65be..324d3fbf 100644
--- a/modules/thai/thai-fc.c
+++ b/modules/thai/thai-fc.c
@@ -110,7 +110,7 @@ static int tis620_2[128] = {
     0x0e20, 0x0e21, 0x0e22, 0x0e23, 0x0e24, 0x0e25, 0x0e26, 0x0e27,
     0x0e28, 0x0e29, 0x0e2a, 0x0e2b, 0x0e2c, 0x0e2d, 0x0e2e, 0x0e2f,
     0x0e30, 0x0e31, 0x0e32, 0x0e33, 0x0e34, 0x0e35, 0x0e36, 0x0e37,
-    0x0e38, 0x0e39, 0x0e3a,      0,      0, 0x25cc,      0, 0x0e3f,
+    0x0e38, 0x0e39, 0x0e3a,      0,      0,      0,      0, 0x0e3f,
     0x0e40, 0x0e41, 0x0e42, 0x0e43, 0x0e44, 0x0e45, 0x0e46, 0x0e47,
     0x0e48, 0x0e49, 0x0e4a, 0x0e4b, 0x0e4c, 0x0e4d, 0x0e4e, 0x0e4f,
     0x0e50, 0x0e51, 0x0e52, 0x0e53, 0x0e54, 0x0e55, 0x0e56, 0x0e57,
@@ -169,20 +169,32 @@ thai_get_font_info (PangoFont *font)
   return font_info;
 }
 
+static gint
+thai_get_glyph_index (ThaiFontInfo *font_info, gchar c)
+{
+  switch (font_info->font_set) {
+    case THAI_FONT_TIS:     return (c & 0x80) ? tis620_0[c & 0x7f] : c;
+    case THAI_FONT_TIS_MAC: return (c & 0x80) ? tis620_1[c & 0x7f] : c;
+    case THAI_FONT_TIS_WIN: return (c & 0x80) ? tis620_2[c & 0x7f] : c;
+    default:                return 0;
+  }
+}
+
+PangoGlyph
+thai_get_glyph_tis (ThaiFontInfo *font_info, gchar c)
+{
+  return pango_fc_font_get_glyph ((PangoFcFont *)font_info->font,
+                                  thai_get_glyph_index (font_info, c));
+}
+
 PangoGlyph
-thai_make_glyph (ThaiFontInfo *font_info, unsigned int c)
+thai_make_glyph_tis (ThaiFontInfo *font_info, gchar c)
 {
-  int index;
+  gint index;
   PangoGlyph result;
   PangoFcFont *fc_font = (PangoFcFont *)font_info->font;
 
-  switch (font_info->font_set) {
-    case THAI_FONT_TIS:     index = (c & 0x80) ? tis620_0[c & 0x7f] : c; break;
-    case THAI_FONT_TIS_MAC: index = (c & 0x80) ? tis620_1[c & 0x7f] : c; break;
-    case THAI_FONT_TIS_WIN: index = (c & 0x80) ? tis620_2[c & 0x7f] : c; break;
-    default:                index = 0; break;
-  }
-  
+  index = thai_get_glyph_index (font_info, c);
   result = pango_fc_font_get_glyph (fc_font, index);
   if (result)
     return result;
@@ -191,9 +203,28 @@ thai_make_glyph (ThaiFontInfo *font_info, unsigned int c)
 }
 
 PangoGlyph
-thai_make_unknown_glyph (ThaiFontInfo *font_info, unsigned int c)
+thai_get_glyph_uni (ThaiFontInfo *font_info, gunichar uc)
+{
+  return pango_fc_font_get_glyph ((PangoFcFont *)font_info->font, uc);
+}
+
+PangoGlyph
+thai_make_glyph_uni (ThaiFontInfo *font_info, gunichar uc)
+{
+  PangoGlyph result;
+  PangoFcFont *fc_font = (PangoFcFont *)font_info->font;
+
+  result = pango_fc_font_get_glyph (fc_font, uc);
+  if (result)
+    return result;
+  else
+    return pango_fc_font_get_unknown_glyph (fc_font, uc);
+}
+
+PangoGlyph
+thai_make_unknown_glyph (ThaiFontInfo *font_info, gunichar uc)
 {
-  return pango_fc_font_get_unknown_glyph ((PangoFcFont *)font_info->font, c);
+  return pango_fc_font_get_unknown_glyph ((PangoFcFont *)font_info->font, uc);
 }
 
 static void
diff --git a/modules/thai/thai-shaper.c b/modules/thai/thai-shaper.c
index f7d99f5d..7c036e9a 100644
--- a/modules/thai/thai-shaper.c
+++ b/modules/thai/thai-shaper.c
@@ -281,6 +281,12 @@ add_glyph (ThaiFontInfo     *font_info,
   glyphs->glyphs[index].geometry.y_offset = 0;
 }
 
+static PangoGlyph
+get_null_base_glyph (ThaiFontInfo *font_info)
+{
+  return thai_get_glyph_uni (font_info, 0x25cc);
+}
+
 static gint
 get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 			  gunichar *cluster,
@@ -293,18 +299,17 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
       case 1:
         if (is_char_type (cluster[0], BelowVowel|BelowDiac|AboveVowel|AboveDiac|Tone))
 	  {
-	    if (font_info->font_set == THAI_FONT_TIS)
-	      glyph_lists[0] = thai_make_glyph (font_info, 0x20);
-	    else
-	      glyph_lists[0] = thai_make_glyph (font_info, 0xDD);
-            glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    return 2;
+	    gint n;
+	    glyph_lists[0] = get_null_base_glyph (font_info);
+	    n = glyph_lists[0] ? 1 : 0;
+            glyph_lists[n++] =
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    return n;
           }
 	else
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
             return 1;
           }
         break;
@@ -314,36 +319,36 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
             is_char_type (cluster[1], SaraAm))
 	  {
             glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-            glyph_lists[1] = thai_make_glyph (font_info, 0xED);
-            glyph_lists[2] = thai_make_glyph (font_info, 0xD2);
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+            glyph_lists[1] = thai_make_glyph_tis (font_info, 0xED);
+            glyph_lists[2] = thai_make_glyph_tis (font_info, 0xD2);
             return 3;
           }
 	else if (is_char_type (cluster[0], UpTailCons) &&
           	 is_char_type (cluster[1], SaraAm))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-            glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+            glyph_lists[1] = thai_make_glyph_tis (font_info,
 					shiftleft_tone_ad (0xED, shaping_table));
-            glyph_lists[2] = thai_make_glyph (font_info, 0xD2);
+            glyph_lists[2] = thai_make_glyph_tis (font_info, 0xD2);
             return 3;
           }
 	else if (is_char_type (cluster[0], NoTailCons|BotTailCons|SpltTailCons) &&
           	 is_char_type (cluster[1], AboveVowel))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
 	    return 2;
           }
 	else if (is_char_type (cluster[0], NoTailCons|BotTailCons|SpltTailCons) &&
           	 is_char_type (cluster[1], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 		    	shiftdown_tone_ad (ucs2tis (cluster[1]), shaping_table));
 	    return 2;
 	  }
@@ -351,8 +356,8 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
           	 is_char_type (cluster[1], AboveVowel))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 		    	shiftleft_av (ucs2tis (cluster[1]), shaping_table));
 	    return 2;
           }
@@ -360,8 +365,8 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
           	 is_char_type (cluster[1], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 			shiftdownleft_tone_ad (ucs2tis (cluster[1]), shaping_table));
 	    return 2;
 	  }
@@ -369,41 +374,40 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
           	 is_char_type (cluster[1], BelowVowel|BelowDiac))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
 	    return 2;
           }
 	else if (is_char_type (cluster[0], BotTailCons) &&
 		 is_char_type (cluster[1], BelowVowel|BelowDiac))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info,
 			shiftdown_bv_bd (ucs2tis (cluster[1]), shaping_table));
 	    return 2;
 	  }
 	else if (is_char_type (cluster[0], SpltTailCons) &&
           	 is_char_type (cluster[1], BelowVowel|BelowDiac))
 	  {
-	    glyph_lists[0] = thai_make_glyph (font_info,
+	    glyph_lists[0] = thai_make_glyph_tis (font_info,
 		    		tailcutcons (ucs2tis (cluster[0]), shaping_table));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
 	    return 2;
 	  }
 	else
 	  {
-	    if (font_info->font_set == THAI_FONT_TIS)
-	      glyph_lists[0] = thai_make_glyph (font_info, 0x20);
-	    else
-	      glyph_lists[0] = thai_make_glyph (font_info, 0xDD);
-	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[2] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
-	    return 3;
+	    gint n;
+	    glyph_lists[0] = get_null_base_glyph (font_info);
+	    n = glyph_lists[0] ? 1 : 0;
+	    glyph_lists[n++] =
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[n++] =
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
+	    return n;
 	  }
         break;
           
@@ -413,11 +417,11 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
             is_char_type (cluster[2], SaraAm))
 	  {
             glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-            glyph_lists[1] = thai_make_glyph (font_info, 0xED);
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+            glyph_lists[1] = thai_make_glyph_tis (font_info, 0xED);
             glyph_lists[2] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
-            glyph_lists[3] = thai_make_glyph (font_info, 0xD2);
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
+            glyph_lists[3] = thai_make_glyph_tis (font_info, 0xD2);
             return 4;
           }
 	else if (is_char_type (cluster[0], UpTailCons) &&
@@ -425,12 +429,12 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[2], SaraAm))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 				shiftleft_tone_ad (0xED, shaping_table));
-	    glyph_lists[2] = thai_make_glyph (font_info,
+	    glyph_lists[2] = thai_make_glyph_tis (font_info,
 		    		shiftleft_tone_ad (ucs2tis (cluster[1]), shaping_table));
-	    glyph_lists[3] = thai_make_glyph (font_info, 0xD2);
+	    glyph_lists[3] = thai_make_glyph_tis (font_info, 0xD2);
 	    return 4;
 	  }
 	else if (is_char_type (cluster[0], UpTailCons) &&
@@ -438,10 +442,10 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[2], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 				shiftleft_av (ucs2tis (cluster[1]), shaping_table));
-	    glyph_lists[2] = thai_make_glyph (font_info,
+	    glyph_lists[2] = thai_make_glyph_tis (font_info,
 		    		shiftleft_tone_ad (ucs2tis (cluster[2]), shaping_table));
 	    return 3;
 	  }
@@ -450,10 +454,10 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[2], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
-	    glyph_lists[2] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
+	    glyph_lists[2] = thai_make_glyph_tis (font_info,
 			shiftdownleft_tone_ad (ucs2tis (cluster[2]), shaping_table));
 	    return 3;
 	  }
@@ -462,11 +466,11 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[2], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
 	    glyph_lists[2] =
-		thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info,
 			shiftdown_tone_ad (ucs2tis (cluster[2]), shaping_table));
 	    return 3;
 	  }
@@ -474,11 +478,11 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[1], BelowVowel) &&
 		 is_char_type (cluster[2], AboveDiac|Tone))
 	  {
-	    glyph_lists[0] = thai_make_glyph (font_info,
+	    glyph_lists[0] = thai_make_glyph_tis (font_info,
 		    		tailcutcons (ucs2tis (cluster[0]), shaping_table));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
-	    glyph_lists[2] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
+	    glyph_lists[2] = thai_make_glyph_tis (font_info,
 		    		shiftdown_tone_ad (ucs2tis (cluster[2]), shaping_table));
 	    return 3;
 	  }
@@ -487,21 +491,21 @@ get_adjusted_glyphs_list (ThaiFontInfo *font_info,
 		 is_char_type (cluster[2], AboveDiac|Tone))
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
-	    glyph_lists[1] = thai_make_glyph (font_info,
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
+	    glyph_lists[1] = thai_make_glyph_tis (font_info,
 		    		shiftdown_bv_bd (ucs2tis (cluster[1]), shaping_table));
-	    glyph_lists[2] = thai_make_glyph (font_info,
+	    glyph_lists[2] = thai_make_glyph_tis (font_info,
 				shiftdown_tone_ad (ucs2tis (cluster[2]), shaping_table));
 	    return 3;
 	  }
 	else
 	  {
 	    glyph_lists[0] =
-		thai_make_glyph (font_info, ucs2tis (cluster[0]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[0]));
 	    glyph_lists[1] =
-		thai_make_glyph (font_info, ucs2tis (cluster[1]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[1]));
 	    glyph_lists[2] =
-		thai_make_glyph (font_info, ucs2tis (cluster[2]));
+		thai_make_glyph_tis (font_info, ucs2tis (cluster[2]));
 	    return 3;
 	  }
       break;
@@ -562,7 +566,7 @@ add_cluster (ThaiFontInfo	*font_info,
     {
       g_assert (num_chrs == 1);
       add_glyph (font_info, glyphs, cluster_start,
-		 thai_make_glyph (font_info, cluster[0]),
+		 thai_make_glyph_uni (font_info, cluster[0]),
 		 FALSE);
     }
   else
diff --git a/modules/thai/thai-shaper.h b/modules/thai/thai-shaper.h
index 675d95ae..19850730 100644
--- a/modules/thai/thai-shaper.h
+++ b/modules/thai/thai-shaper.h
@@ -34,10 +34,19 @@ ThaiFontInfo *
 thai_get_font_info (PangoFont *font);
 
 PangoGlyph
-thai_make_glyph (ThaiFontInfo *font_info, unsigned int c);
+thai_get_glyph_tis (ThaiFontInfo *font_info, gchar c);
 
 PangoGlyph
-thai_make_unknown_glyph (ThaiFontInfo *font_info, unsigned int c);
+thai_make_glyph_tis (ThaiFontInfo *font_info, gchar c);
+
+PangoGlyph
+thai_get_glyph_uni (ThaiFontInfo *font_info, gunichar uc);
+
+PangoGlyph
+thai_make_glyph_uni (ThaiFontInfo *font_info, gunichar uc);
+
+PangoGlyph
+thai_make_unknown_glyph (ThaiFontInfo *font_info, gunichar uc);
 
 /*
  * Public functions