Fix handling of EBDT formats 8 and 9 (part 2).

ChangeLog

@@ -1,3 +1,33 @@
+2009-03-09  Alexey Kryukov  <anagnost@yandex.ru>
+
+	Fix handling of EBDT formats 8 and 9 (part 2).
+
+	This patch fixes the following problems in ttsbit0.c:
+
+	. Bitmaps for compound glyphs were never allocated.
+
+	. `SBitDecoder' refused to load metrics if some other metrics have
+	  already been loaded.  This condition certainly makes no sense for
+	  recursive calls, so I've just disabled it.  Another possibility
+	  would be resetting `decoder->metrics_loaded' to false before
+	  loading each composite component.  However, we must restore the
+	  original metrics after finishing the recursion; otherwise we can
+	  get a misaligned glyph.
+
+	. `tt_sbit_decoder_load_bit_aligned' incorrectly handled `x_pos',
+	  causing some glyph components to be shifted too far to the right
+	  (especially noticeable for small sizes).
+
+	Note that support for grayscale bitmaps (not necessarily compound) is
+	completely broken in ttsbit0.c.
+
+	* src/sfnt/tt_sbit_decoder_load_metrics: Always load metrics.
+	(tt_sbit_decoder_load_bit_aligned): Handle `x_pos' correctly in case
+	of `h == height'.
+	(tt_sbit_decoder_load_compound): Reset metrics after loading
+	components.
+	Allocate bitmap.
+
 2009-03-09  Werner Lemberg  <wl@gnu.org>
 
 	* builds/unix/configure.raw (version_info): Set to 9:20:3.

src/sfnt/ttsbit0.c

@@ -324,14 +324,11 @@
     if ( p + 5 > limit )
       goto Fail;
 
-    if ( !decoder->metrics_loaded )
-    {
-      metrics->height       = p[0];
-      metrics->width        = p[1];
-      metrics->horiBearingX = (FT_Char)p[2];
-      metrics->horiBearingY = (FT_Char)p[3];
-      metrics->horiAdvance  = p[4];
-    }
+    metrics->height       = p[0];
+    metrics->width        = p[1];
+    metrics->horiBearingX = (FT_Char)p[2];
+    metrics->horiBearingY = (FT_Char)p[3];
+    metrics->horiAdvance  = p[4];
 
     p += 5;
     if ( big )
@@ -339,12 +336,9 @@
       if ( p + 3 > limit )
         goto Fail;
 
-      if ( !decoder->metrics_loaded )
-      {
-        metrics->vertBearingX = (FT_Char)p[0];
-        metrics->vertBearingY = (FT_Char)p[1];
-        metrics->vertAdvance  = p[2];
-      }
+      metrics->vertBearingX = (FT_Char)p[0];
+      metrics->vertBearingY = (FT_Char)p[1];
+      metrics->vertAdvance  = p[2];
 
       p += 3;
     }
@@ -537,7 +531,12 @@
       {
         w = ( width < 8 - x_pos ) ? width : 8 - x_pos;
 
-        if ( nbits < w )
+        if ( h == height )
+        {
+          rval  |= *p++;
+          nbits += x_pos;
+        }
+        else if ( nbits < w )
         {
           rval  |= *p++;
           nbits += 8 - w;
@@ -548,7 +547,8 @@
           nbits  -= w;
         }
 
-        *write++ |= ( ( rval >> nbits ) & 0xFF ) & ~( 0xFF << w );
+        *write++ |= ( ( rval >> nbits ) & 0xFF ) &
+                    ( ~( 0xFF << w ) << ( 8 - w - x_pos ) );
         rval    <<= 8;
 
         w = width - w;
@@ -595,6 +595,13 @@
     FT_Error  error = SFNT_Err_Ok;
     FT_UInt   num_components, nn;
 
+    FT_Char  horiBearingX = decoder->metrics->horiBearingX;
+    FT_Char  horiBearingY = decoder->metrics->horiBearingY;
+    FT_Byte  horiAdvance  = decoder->metrics->horiAdvance;
+    FT_Char  vertBearingX = decoder->metrics->vertBearingX;
+    FT_Char  vertBearingY = decoder->metrics->vertBearingY;
+    FT_Byte  vertAdvance  = decoder->metrics->vertAdvance;
+
 
     if ( p + 2 > limit )
       goto Fail;
@@ -603,6 +610,13 @@
     if ( p + 4 * num_components > limit )
       goto Fail;
 
+    if ( !decoder->bitmap_allocated )
+    {
+      error = tt_sbit_decoder_alloc_bitmap( decoder );
+      if ( error )
+        goto Exit;
+    }
+
     for ( nn = 0; nn < num_components; nn++ )
     {
       FT_UInt  gindex = FT_NEXT_USHORT( p );
@@ -617,6 +631,15 @@
         break;
     }
 
+    decoder->metrics->horiBearingX = horiBearingX;
+    decoder->metrics->horiBearingY = horiBearingY;
+    decoder->metrics->horiAdvance  = horiAdvance;
+    decoder->metrics->vertBearingX = vertBearingX;
+    decoder->metrics->vertBearingY = vertBearingY;
+    decoder->metrics->vertAdvance  = vertAdvance;
+    decoder->metrics->width        = (FT_UInt)decoder->bitmap->width;
+    decoder->metrics->height       = (FT_UInt)decoder->bitmap->rows;
+
   Exit:
     return error;