shithub: freetype+ttf2subf

Info  •  Files  •  Log  •  Branches

[sfnt] Speed up `sbix' lookup.

This also fixes a bug introduced in 2016-10-01 which prevents
display of embedded bitmap fonts that use the `sbix' format.

* src/sfnt/ttsbit.c (tt_face_load_sbit): Store `sbix' size and
offset also in `ebdt_size' and `ebdt_start', respectively.  This
makes the test for an embedded bitmap data table succeed for this
format.

(tt_face_load_strike_metrics) <TT_SBIT_TABLE_TYPE_SBIX>: Use
`ebdt_size' and `ebdt_start'
(tt_face_load_sbix_image): Ditto.

git/fs: mount .git/fs: mount/attach disallowed

--- a/ChangeLog

+++ b/ChangeLog

@@ -1,3 +1,19 @@

+2016-11-06  Werner Lemberg  <[email protected]>

+

+	[sfnt] Speed up `sbix' lookup.

+

+	This also fixes a bug introduced in 2016-10-01 which prevents

+	display of embedded bitmap fonts that use the `sbix' format.

+

+	* src/sfnt/ttsbit.c (tt_face_load_sbit): Store `sbix' size and

+	offset also in `ebdt_size' and `ebdt_start', respectively.  This

+	makes the test for an embedded bitmap data table succeed for this

+	format.

+

+	(tt_face_load_strike_metrics) <TT_SBIT_TABLE_TYPE_SBIX>: Use

+	`ebdt_size' and `ebdt_start'

+	(tt_face_load_sbix_image): Ditto.

+

 2016-11-06  Seigo Nonaka  <[email protected]>

 	    Werner Lemberg  <[email protected]>

--- a/src/sfnt/ttsbit.c

+++ b/src/sfnt/ttsbit.c

@@ -48,6 +48,7 @@

   {

     FT_Error  error;

     FT_ULong  table_size;

+    FT_ULong  table_start;

     face->sbit_table       = NULL;

@@ -83,6 +84,8 @@

       goto Exit;

     }

+    table_start = FT_STREAM_POS();

+

     switch ( (FT_UInt)face->sbit_table_type )

     {

     case TT_SBIT_TABLE_TYPE_EBLC:

@@ -202,8 +205,15 @@

     face->ebdt_start = 0;

     face->ebdt_size  = 0;

-    if ( face->sbit_table_type != TT_SBIT_TABLE_TYPE_NONE )

+    if ( face->sbit_table_type == TT_SBIT_TABLE_TYPE_SBIX )

     {

+      /* the `sbix' table is self-contained; */

+      /* it has no associated data table     */

+      face->ebdt_start = table_start;

+      face->ebdt_size  = table_size;

+    }

+    else if ( face->sbit_table_type != TT_SBIT_TABLE_TYPE_NONE )

+    {

       FT_ULong  ebdt_size;

@@ -389,7 +399,6 @@

         FT_UInt         offset;

         FT_UShort       upem, ppem, resolution;

         TT_HoriHeader  *hori;

-        FT_ULong        table_size;

         FT_Pos          ppem_; /* to reduce casts */

         FT_Error  error;

@@ -399,15 +408,11 @@

         p      = face->sbit_table + 8 + 4 * strike_index;

         offset = FT_NEXT_ULONG( p );

-        error = face->goto_table( face, TTAG_sbix, stream, &table_size );

-        if ( error )

-          return error;

-

-        if ( offset + 4  > table_size )

+        if ( offset + 4 > face->ebdt_size )

           return FT_THROW( Invalid_File_Format );

-        if ( FT_STREAM_SEEK( FT_STREAM_POS() + offset ) ||

-             FT_FRAME_ENTER( 4 )                        )

+        if ( FT_STREAM_SEEK( face->ebdt_start + offset ) ||

+             FT_FRAME_ENTER( 4 )                         )

           return error;

         ppem       = FT_GET_USHORT();

@@ -1440,8 +1445,7 @@

                            FT_Bitmap           *map,

                            TT_SBit_MetricsRec  *metrics )

   {

-    FT_UInt   sbix_pos, strike_offset, glyph_start, glyph_end;

-    FT_ULong  table_size;

+    FT_UInt   strike_offset, glyph_start, glyph_end;

     FT_Int    originOffsetX, originOffsetY;

     FT_Tag    graphicType;

     FT_Int    recurse_depth = 0;

@@ -1460,21 +1464,18 @@

     p = face->sbit_table + 8 + 4 * strike_index;

     strike_offset = FT_NEXT_ULONG( p );

-    error = face->goto_table( face, TTAG_sbix, stream, &table_size );

-    if ( error )

-      return error;

-    sbix_pos = FT_STREAM_POS();

-

   retry:

     if ( glyph_index > (FT_UInt)face->root.num_glyphs )

       return FT_THROW( Invalid_Argument );

-    if ( strike_offset >= table_size                          ||

-         table_size - strike_offset < 4 + glyph_index * 4 + 8 )

+    if ( strike_offset >= face->ebdt_size                          ||

+         face->ebdt_size - strike_offset < 4 + glyph_index * 4 + 8 )

       return FT_THROW( Invalid_File_Format );

-    if ( FT_STREAM_SEEK( sbix_pos + strike_offset + 4 + glyph_index * 4 ) ||

-         FT_FRAME_ENTER( 8 )                                              )

+    if ( FT_STREAM_SEEK( face->ebdt_start  +

+                         strike_offset + 4 +

+                         glyph_index * 4   ) ||

+         FT_FRAME_ENTER( 8 )                 )

       return error;

     glyph_start = FT_GET_ULONG();

@@ -1484,13 +1485,13 @@

     if ( glyph_start == glyph_end )

       return FT_THROW( Invalid_Argument );

-    if ( glyph_start > glyph_end                ||

-         glyph_end - glyph_start < 8            ||

-         table_size - strike_offset < glyph_end )

+    if ( glyph_start > glyph_end                     ||

+         glyph_end - glyph_start < 8                 ||

+         face->ebdt_size - strike_offset < glyph_end )

       return FT_THROW( Invalid_File_Format );

-    if ( FT_STREAM_SEEK( sbix_pos + strike_offset + glyph_start ) ||

-         FT_FRAME_ENTER( glyph_end - glyph_start )                )

+    if ( FT_STREAM_SEEK( face->ebdt_start + strike_offset + glyph_start ) ||

+         FT_FRAME_ENTER( glyph_end - glyph_start )                        )

       return error;

     originOffsetX = FT_GET_SHORT();