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authorWlodekM <[email protected]>2024-06-16 10:35:45 +0300
committerWlodekM <[email protected]>2024-06-16 10:35:45 +0300
commitabef6da56913f1c55528103e60a50451a39628b1 (patch)
treeb3c8092471ecbb73e568cd0d336efa0e7871ee8d /src/freetype/ttgload.c
initial commit
Diffstat (limited to 'src/freetype/ttgload.c')
-rw-r--r--src/freetype/ttgload.c2558
1 files changed, 2558 insertions, 0 deletions
diff --git a/src/freetype/ttgload.c b/src/freetype/ttgload.c
new file mode 100644
index 0000000..df07b41
--- /dev/null
+++ b/src/freetype/ttgload.c
@@ -0,0 +1,2558 @@
+/***************************************************************************/
+/*                                                                         */
+/*  ttgload.c                                                              */
+/*                                                                         */
+/*    TrueType Glyph Loader (body).                                        */
+/*                                                                         */
+/*  Copyright 1996-2018 by                                                 */
+/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
+/*                                                                         */
+/*  This file is part of the FreeType project, and may only be used,       */
+/*  modified, and distributed under the terms of the FreeType project      */
+/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
+/*  this file you indicate that you have read the license and              */
+/*  understand and accept it fully.                                        */
+/*                                                                         */
+/***************************************************************************/
+
+
+#include "ft2build.h"
+#include FT_INTERNAL_DEBUG_H
+#include FT_CONFIG_CONFIG_H
+#include FT_INTERNAL_CALC_H
+#include FT_INTERNAL_STREAM_H
+#include FT_INTERNAL_SFNT_H
+#include FT_TRUETYPE_TAGS_H
+#include FT_OUTLINE_H
+#include FT_DRIVER_H
+#include FT_LIST_H
+
+#include "ttgload.h"
+#include "ttpload.h"
+
+#include "tterrors.h"
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
+  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
+  /* messages during execution.                                            */
+  /*                                                                       */
+#undef  FT_COMPONENT
+#define FT_COMPONENT  trace_ttgload
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* Composite glyph flags.                                                */
+  /*                                                                       */
+#define ARGS_ARE_WORDS             0x0001
+#define ARGS_ARE_XY_VALUES         0x0002
+#define ROUND_XY_TO_GRID           0x0004
+#define WE_HAVE_A_SCALE            0x0008
+/* reserved                        0x0010 */
+#define MORE_COMPONENTS            0x0020
+#define WE_HAVE_AN_XY_SCALE        0x0040
+#define WE_HAVE_A_2X2              0x0080
+#define WE_HAVE_INSTR              0x0100
+#define USE_MY_METRICS             0x0200
+#define OVERLAP_COMPOUND           0x0400
+#define SCALED_COMPONENT_OFFSET    0x0800
+#define UNSCALED_COMPONENT_OFFSET  0x1000
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* Return the horizontal metrics in font units for a given glyph.        */
+  /*                                                                       */
+  FT_LOCAL_DEF( void )
+  TT_Get_HMetrics( TT_Face     face,
+                   FT_UInt     idx,
+                   FT_Short*   lsb,
+                   FT_UShort*  aw )
+  {
+    ( (SFNT_Service)face->sfnt )->get_metrics( face, 0, idx, lsb, aw );
+
+    FT_TRACE5(( "  advance width (font units): %d\n", *aw ));
+    FT_TRACE5(( "  left side bearing (font units): %d\n", *lsb ));
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* Return the vertical metrics in font units for a given glyph.          */
+  /* See function `tt_loader_set_pp' below for explanations.               */
+  /*                                                                       */
+  FT_LOCAL_DEF( void )
+  TT_Get_VMetrics( TT_Face     face,
+                   FT_UInt     idx,
+                   FT_Pos      yMax,
+                   FT_Short*   tsb,
+                   FT_UShort*  ah )
+  {
+    if ( face->vertical_info )
+      ( (SFNT_Service)face->sfnt )->get_metrics( face, 1, idx, tsb, ah );
+
+    else if ( face->os2.version != 0xFFFFU )
+    {
+      *tsb = (FT_Short)( face->os2.sTypoAscender - yMax );
+      *ah  = (FT_UShort)FT_ABS( face->os2.sTypoAscender -
+                                face->os2.sTypoDescender );
+    }
+
+    else
+    {
+      *tsb = (FT_Short)( face->horizontal.Ascender - yMax );
+      *ah  = (FT_UShort)FT_ABS( face->horizontal.Ascender -
+                                face->horizontal.Descender );
+    }
+
+    FT_TRACE5(( "  advance height (font units): %d\n", *ah ));
+    FT_TRACE5(( "  top side bearing (font units): %d\n", *tsb ));
+  }
+
+
+  static FT_Error
+  tt_get_metrics( TT_Loader  loader,
+                  FT_UInt    glyph_index )
+  {
+    TT_Face    face   = loader->face;
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
+#endif
+
+    FT_Error   error;
+    FT_Stream  stream = loader->stream;
+
+    FT_Short   left_bearing = 0, top_bearing = 0;
+    FT_UShort  advance_width = 0, advance_height = 0;
+
+    /* we must preserve the stream position          */
+    /* (which gets altered by the metrics functions) */
+    FT_ULong  pos = FT_STREAM_POS();
+
+
+    TT_Get_HMetrics( face, glyph_index,
+                     &left_bearing,
+                     &advance_width );
+    TT_Get_VMetrics( face, glyph_index,
+                     loader->bbox.yMax,
+                     &top_bearing,
+                     &advance_height );
+
+    if ( FT_STREAM_SEEK( pos ) )
+      return error;
+
+    loader->left_bearing = left_bearing;
+    loader->advance      = advance_width;
+    loader->top_bearing  = top_bearing;
+    loader->vadvance     = advance_height;
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 &&
+         loader->exec                                             )
+    {
+      loader->exec->sph_tweak_flags = 0;
+
+      /* This may not be the right place for this, but it works...  */
+      /* Note that we have to unconditionally load the tweaks since */
+      /* it is possible that glyphs individually switch ClearType's */
+      /* backward compatibility mode on and off.                    */
+      sph_set_tweaks( loader, glyph_index );
+    }
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+    if ( !loader->linear_def )
+    {
+      loader->linear_def = 1;
+      loader->linear     = advance_width;
+    }
+
+    return FT_Err_Ok;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* The following functions are used by default with TrueType fonts.      */
+  /* However, they can be replaced by alternatives if we need to support   */
+  /* TrueType-compressed formats (like MicroType) in the future.           */
+  /*                                                                       */
+  /*************************************************************************/
+
+  FT_CALLBACK_DEF( FT_Error )
+  TT_Access_Glyph_Frame( TT_Loader  loader,
+                         FT_UInt    glyph_index,
+                         FT_ULong   offset,
+                         FT_UInt    byte_count )
+  {
+    FT_Error   error;
+    FT_Stream  stream = loader->stream;
+
+    /* for non-debug mode */
+    FT_UNUSED( glyph_index );
+
+
+    FT_TRACE4(( "Glyph %ld\n", glyph_index ));
+
+    /* the following line sets the `error' variable through macros! */
+    if ( FT_STREAM_SEEK( offset ) || FT_FRAME_ENTER( byte_count ) )
+      return error;
+
+    loader->cursor = stream->cursor;
+    loader->limit  = stream->limit;
+
+    return FT_Err_Ok;
+  }
+
+
+  FT_CALLBACK_DEF( void )
+  TT_Forget_Glyph_Frame( TT_Loader  loader )
+  {
+    FT_Stream  stream = loader->stream;
+
+
+    FT_FRAME_EXIT();
+  }
+
+
+  FT_CALLBACK_DEF( FT_Error )
+  TT_Load_Glyph_Header( TT_Loader  loader )
+  {
+    FT_Byte*  p     = loader->cursor;
+    FT_Byte*  limit = loader->limit;
+
+
+    if ( p + 10 > limit )
+      return FT_THROW( Invalid_Outline );
+
+    loader->n_contours = FT_NEXT_SHORT( p );
+
+    loader->bbox.xMin = FT_NEXT_SHORT( p );
+    loader->bbox.yMin = FT_NEXT_SHORT( p );
+    loader->bbox.xMax = FT_NEXT_SHORT( p );
+    loader->bbox.yMax = FT_NEXT_SHORT( p );
+
+    FT_TRACE5(( "  # of contours: %d\n", loader->n_contours ));
+    FT_TRACE5(( "  xMin: %4d  xMax: %4d\n", loader->bbox.xMin,
+                                            loader->bbox.xMax ));
+    FT_TRACE5(( "  yMin: %4d  yMax: %4d\n", loader->bbox.yMin,
+                                            loader->bbox.yMax ));
+    loader->cursor = p;
+
+    return FT_Err_Ok;
+  }
+
+
+  FT_CALLBACK_DEF( FT_Error )
+  TT_Load_Simple_Glyph( TT_Loader  load )
+  {
+    FT_Error        error;
+    FT_Byte*        p          = load->cursor;
+    FT_Byte*        limit      = load->limit;
+    FT_GlyphLoader  gloader    = load->gloader;
+    FT_Int          n_contours = load->n_contours;
+    FT_Outline*     outline;
+    FT_UShort       n_ins;
+    FT_Int          n_points;
+
+    FT_Byte         *flag, *flag_limit;
+    FT_Byte         c, count;
+    FT_Vector       *vec, *vec_limit;
+    FT_Pos          x;
+    FT_Short        *cont, *cont_limit, prev_cont;
+    FT_Int          xy_size = 0;
+
+
+    /* check that we can add the contours to the glyph */
+    error = FT_GLYPHLOADER_CHECK_POINTS( gloader, 0, n_contours );
+    if ( error )
+      goto Fail;
+
+    /* reading the contours' endpoints & number of points */
+    cont       = gloader->current.outline.contours;
+    cont_limit = cont + n_contours;
+
+    /* check space for contours array + instructions count */
+    if ( n_contours >= 0xFFF || p + ( n_contours + 1 ) * 2 > limit )
+      goto Invalid_Outline;
+
+    prev_cont = FT_NEXT_SHORT( p );
+
+    if ( n_contours > 0 )
+      cont[0] = prev_cont;
+
+    if ( prev_cont < 0 )
+      goto Invalid_Outline;
+
+    for ( cont++; cont < cont_limit; cont++ )
+    {
+      cont[0] = FT_NEXT_SHORT( p );
+      if ( cont[0] <= prev_cont )
+      {
+        /* unordered contours: this is invalid */
+        goto Invalid_Outline;
+      }
+      prev_cont = cont[0];
+    }
+
+    n_points = 0;
+    if ( n_contours > 0 )
+    {
+      n_points = cont[-1] + 1;
+      if ( n_points < 0 )
+        goto Invalid_Outline;
+    }
+
+    /* note that we will add four phantom points later */
+    error = FT_GLYPHLOADER_CHECK_POINTS( gloader, n_points + 4, 0 );
+    if ( error )
+      goto Fail;
+
+    /* reading the bytecode instructions */
+    load->glyph->control_len  = 0;
+    load->glyph->control_data = NULL;
+
+    if ( p + 2 > limit )
+      goto Invalid_Outline;
+
+    n_ins = FT_NEXT_USHORT( p );
+
+    FT_TRACE5(( "  Instructions size: %u\n", n_ins ));
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+    if ( IS_HINTED( load->load_flags ) )
+    {
+      FT_ULong  tmp;
+
+
+      /* check instructions size */
+      if ( ( limit - p ) < n_ins )
+      {
+        FT_TRACE1(( "TT_Load_Simple_Glyph: instruction count mismatch\n" ));
+        error = FT_THROW( Too_Many_Hints );
+        goto Fail;
+      }
+
+      /* we don't trust `maxSizeOfInstructions' in the `maxp' table */
+      /* and thus update the bytecode array size by ourselves       */
+
+      tmp   = load->exec->glyphSize;
+      error = Update_Max( load->exec->memory,
+                          &tmp,
+                          sizeof ( FT_Byte ),
+                          (void*)&load->exec->glyphIns,
+                          n_ins );
+
+      load->exec->glyphSize = (FT_UShort)tmp;
+      if ( error )
+        return error;
+
+      load->glyph->control_len  = n_ins;
+      load->glyph->control_data = load->exec->glyphIns;
+
+      if ( n_ins )
+        FT_MEM_COPY( load->exec->glyphIns, p, (FT_Long)n_ins );
+    }
+
+#endif /* TT_USE_BYTECODE_INTERPRETER */
+
+    p += n_ins;
+
+    outline = &gloader->current.outline;
+
+    /* reading the point tags */
+    flag       = (FT_Byte*)outline->tags;
+    flag_limit = flag + n_points;
+
+    FT_ASSERT( flag );
+
+    while ( flag < flag_limit )
+    {
+      if ( p + 1 > limit )
+        goto Invalid_Outline;
+
+      *flag++ = c = FT_NEXT_BYTE( p );
+      if ( c & 8 )
+      {
+        if ( p + 1 > limit )
+          goto Invalid_Outline;
+
+        count = FT_NEXT_BYTE( p );
+        if ( flag + (FT_Int)count > flag_limit )
+          goto Invalid_Outline;
+
+        for ( ; count > 0; count-- )
+          *flag++ = c;
+      }
+    }
+
+    /* reading the X coordinates */
+
+    vec       = outline->points;
+    vec_limit = vec + n_points;
+    flag      = (FT_Byte*)outline->tags;
+    x         = 0;
+
+    if ( p + xy_size > limit )
+      goto Invalid_Outline;
+
+    for ( ; vec < vec_limit; vec++, flag++ )
+    {
+      FT_Pos   y = 0;
+      FT_Byte  f = *flag;
+
+
+      if ( f & 2 )
+      {
+        if ( p + 1 > limit )
+          goto Invalid_Outline;
+
+        y = (FT_Pos)FT_NEXT_BYTE( p );
+        if ( ( f & 16 ) == 0 )
+          y = -y;
+      }
+      else if ( ( f & 16 ) == 0 )
+      {
+        if ( p + 2 > limit )
+          goto Invalid_Outline;
+
+        y = (FT_Pos)FT_NEXT_SHORT( p );
+      }
+
+      x     += y;
+      vec->x = x;
+      /* the cast is for stupid compilers */
+      *flag  = (FT_Byte)( f & ~( 2 | 16 ) );
+    }
+
+    /* reading the Y coordinates */
+
+    vec       = gloader->current.outline.points;
+    vec_limit = vec + n_points;
+    flag      = (FT_Byte*)outline->tags;
+    x         = 0;
+
+    for ( ; vec < vec_limit; vec++, flag++ )
+    {
+      FT_Pos   y = 0;
+      FT_Byte  f = *flag;
+
+
+      if ( f & 4 )
+      {
+        if ( p + 1 > limit )
+          goto Invalid_Outline;
+
+        y = (FT_Pos)FT_NEXT_BYTE( p );
+        if ( ( f & 32 ) == 0 )
+          y = -y;
+      }
+      else if ( ( f & 32 ) == 0 )
+      {
+        if ( p + 2 > limit )
+          goto Invalid_Outline;
+
+        y = (FT_Pos)FT_NEXT_SHORT( p );
+      }
+
+      x     += y;
+      vec->y = x;
+      /* the cast is for stupid compilers */
+      *flag  = (FT_Byte)( f & FT_CURVE_TAG_ON );
+    }
+
+    outline->n_points   = (FT_Short)n_points;
+    outline->n_contours = (FT_Short)n_contours;
+
+    load->cursor = p;
+
+  Fail:
+    return error;
+
+  Invalid_Outline:
+    error = FT_THROW( Invalid_Outline );
+    goto Fail;
+  }
+
+
+  FT_CALLBACK_DEF( FT_Error )
+  TT_Load_Composite_Glyph( TT_Loader  loader )
+  {
+    FT_Error        error;
+    FT_Byte*        p       = loader->cursor;
+    FT_Byte*        limit   = loader->limit;
+    FT_GlyphLoader  gloader = loader->gloader;
+    FT_SubGlyph     subglyph;
+    FT_UInt         num_subglyphs;
+
+
+    num_subglyphs = 0;
+
+    do
+    {
+      FT_Fixed  xx, xy, yy, yx;
+      FT_UInt   count;
+
+
+      /* check that we can load a new subglyph */
+      error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs + 1 );
+      if ( error )
+        goto Fail;
+
+      /* check space */
+      if ( p + 4 > limit )
+        goto Invalid_Composite;
+
+      subglyph = gloader->current.subglyphs + num_subglyphs;
+
+      subglyph->arg1 = subglyph->arg2 = 0;
+
+      subglyph->flags = FT_NEXT_USHORT( p );
+      subglyph->index = FT_NEXT_USHORT( p );
+
+      /* check space */
+      count = 2;
+      if ( subglyph->flags & ARGS_ARE_WORDS )
+        count += 2;
+      if ( subglyph->flags & WE_HAVE_A_SCALE )
+        count += 2;
+      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
+        count += 4;
+      else if ( subglyph->flags & WE_HAVE_A_2X2 )
+        count += 8;
+
+      if ( p + count > limit )
+        goto Invalid_Composite;
+
+      /* read arguments */
+      if ( subglyph->flags & ARGS_ARE_XY_VALUES )
+      {
+        if ( subglyph->flags & ARGS_ARE_WORDS )
+        {
+          subglyph->arg1 = FT_NEXT_SHORT( p );
+          subglyph->arg2 = FT_NEXT_SHORT( p );
+        }
+        else
+        {
+          subglyph->arg1 = FT_NEXT_CHAR( p );
+          subglyph->arg2 = FT_NEXT_CHAR( p );
+        }
+      }
+      else
+      {
+        if ( subglyph->flags & ARGS_ARE_WORDS )
+        {
+          subglyph->arg1 = (FT_Int)FT_NEXT_USHORT( p );
+          subglyph->arg2 = (FT_Int)FT_NEXT_USHORT( p );
+        }
+        else
+        {
+          subglyph->arg1 = (FT_Int)FT_NEXT_BYTE( p );
+          subglyph->arg2 = (FT_Int)FT_NEXT_BYTE( p );
+        }
+      }
+
+      /* read transform */
+      xx = yy = 0x10000L;
+      xy = yx = 0;
+
+      if ( subglyph->flags & WE_HAVE_A_SCALE )
+      {
+        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+        yy = xx;
+      }
+      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
+      {
+        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+        yy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+      }
+      else if ( subglyph->flags & WE_HAVE_A_2X2 )
+      {
+        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+        yx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+        xy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+        yy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
+      }
+
+      subglyph->transform.xx = xx;
+      subglyph->transform.xy = xy;
+      subglyph->transform.yx = yx;
+      subglyph->transform.yy = yy;
+
+      num_subglyphs++;
+
+    } while ( subglyph->flags & MORE_COMPONENTS );
+
+    gloader->current.num_subglyphs = num_subglyphs;
+    FT_TRACE5(( "  %d component%s\n",
+                num_subglyphs,
+                num_subglyphs > 1 ? "s" : "" ));
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+    {
+      FT_UInt  i;
+
+
+      subglyph = gloader->current.subglyphs;
+
+      for ( i = 0; i < num_subglyphs; i++ )
+      {
+        if ( num_subglyphs > 1 )
+          FT_TRACE7(( "    subglyph %d:\n", i ));
+
+        FT_TRACE7(( "      glyph index: %d\n", subglyph->index ));
+
+        if ( subglyph->flags & ARGS_ARE_XY_VALUES )
+          FT_TRACE7(( "      offset: x=%d, y=%d\n",
+                      subglyph->arg1,
+                      subglyph->arg2 ));
+        else
+          FT_TRACE7(( "      matching points: base=%d, component=%d\n",
+                      subglyph->arg1,
+                      subglyph->arg2 ));
+
+        if ( subglyph->flags & WE_HAVE_A_SCALE )
+          FT_TRACE7(( "      scaling: %f\n",
+                      subglyph->transform.xx / 65536.0 ));
+        else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
+          FT_TRACE7(( "      scaling: x=%f, y=%f\n",
+                      subglyph->transform.xx / 65536.0,
+                      subglyph->transform.yy / 65536.0 ));
+        else if ( subglyph->flags & WE_HAVE_A_2X2 )
+          FT_TRACE7(( "      scaling: xx=%f, yx=%f\n"
+                      "               xy=%f, yy=%f\n",
+                      subglyph->transform.xx / 65536.0,
+                      subglyph->transform.yx / 65536.0,
+                      subglyph->transform.xy / 65536.0,
+                      subglyph->transform.yy / 65536.0 ));
+
+        subglyph++;
+      }
+    }
+#endif /* FT_DEBUG_LEVEL_TRACE */
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+    {
+      FT_Stream  stream = loader->stream;
+
+
+      /* we must undo the FT_FRAME_ENTER in order to point */
+      /* to the composite instructions, if we find some.   */
+      /* We will process them later.                       */
+      /*                                                   */
+      loader->ins_pos = (FT_ULong)( FT_STREAM_POS() +
+                                    p - limit );
+    }
+
+#endif
+
+    loader->cursor = p;
+
+  Fail:
+    return error;
+
+  Invalid_Composite:
+    error = FT_THROW( Invalid_Composite );
+    goto Fail;
+  }
+
+
+  FT_LOCAL_DEF( void )
+  TT_Init_Glyph_Loading( TT_Face  face )
+  {
+    face->access_glyph_frame   = TT_Access_Glyph_Frame;
+    face->read_glyph_header    = TT_Load_Glyph_Header;
+    face->read_simple_glyph    = TT_Load_Simple_Glyph;
+    face->read_composite_glyph = TT_Load_Composite_Glyph;
+    face->forget_glyph_frame   = TT_Forget_Glyph_Frame;
+  }
+
+
+  static void
+  tt_prepare_zone( TT_GlyphZone  zone,
+                   FT_GlyphLoad  load,
+                   FT_UInt       start_point,
+                   FT_UInt       start_contour )
+  {
+    zone->n_points    = (FT_UShort)load->outline.n_points -
+                          (FT_UShort)start_point;
+    zone->n_contours  = load->outline.n_contours -
+                          (FT_Short)start_contour;
+    zone->org         = load->extra_points + start_point;
+    zone->cur         = load->outline.points + start_point;
+    zone->orus        = load->extra_points2 + start_point;
+    zone->tags        = (FT_Byte*)load->outline.tags + start_point;
+    zone->contours    = (FT_UShort*)load->outline.contours + start_contour;
+    zone->first_point = (FT_UShort)start_point;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    TT_Hint_Glyph                                                      */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    Hint the glyph using the zone prepared by the caller.  Note that   */
+  /*    the zone is supposed to include four phantom points.               */
+  /*                                                                       */
+  static FT_Error
+  TT_Hint_Glyph( TT_Loader  loader,
+                 FT_Bool    is_composite )
+  {
+#if defined TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY || \
+    defined TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    TT_Face    face   = loader->face;
+    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
+#endif
+
+    TT_GlyphZone  zone = &loader->zone;
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+    FT_Long       n_ins;
+#else
+    FT_UNUSED( is_composite );
+#endif
+
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+    if ( loader->glyph->control_len > 0xFFFFL )
+    {
+      FT_TRACE1(( "TT_Hint_Glyph: too long instructions" ));
+      FT_TRACE1(( " (0x%lx byte) is truncated\n",
+                  loader->glyph->control_len ));
+    }
+    n_ins = loader->glyph->control_len;
+
+    /* save original point position in org */
+    if ( n_ins > 0 )
+      FT_ARRAY_COPY( zone->org, zone->cur, zone->n_points );
+
+    /* Reset graphics state. */
+    loader->exec->GS = loader->size->GS;
+
+    /* XXX: UNDOCUMENTED! Hinting instructions of a composite glyph */
+    /*      completely refer to the (already) hinted subglyphs.     */
+    if ( is_composite )
+    {
+      loader->exec->metrics.x_scale = 1 << 16;
+      loader->exec->metrics.y_scale = 1 << 16;
+
+      FT_ARRAY_COPY( zone->orus, zone->cur, zone->n_points );
+    }
+    else
+    {
+      loader->exec->metrics.x_scale = loader->size->metrics->x_scale;
+      loader->exec->metrics.y_scale = loader->size->metrics->y_scale;
+    }
+#endif
+
+    /* round phantom points */
+    zone->cur[zone->n_points - 4].x =
+      FT_PIX_ROUND( zone->cur[zone->n_points - 4].x );
+    zone->cur[zone->n_points - 3].x =
+      FT_PIX_ROUND( zone->cur[zone->n_points - 3].x );
+    zone->cur[zone->n_points - 2].y =
+      FT_PIX_ROUND( zone->cur[zone->n_points - 2].y );
+    zone->cur[zone->n_points - 1].y =
+      FT_PIX_ROUND( zone->cur[zone->n_points - 1].y );
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+    if ( n_ins > 0 )
+    {
+      FT_Error  error;
+
+      FT_GlyphLoader  gloader         = loader->gloader;
+      FT_Outline      current_outline = gloader->current.outline;
+
+
+      TT_Set_CodeRange( loader->exec, tt_coderange_glyph,
+                        loader->exec->glyphIns, n_ins );
+
+      loader->exec->is_composite = is_composite;
+      loader->exec->pts          = *zone;
+
+      error = TT_Run_Context( loader->exec );
+      if ( error && loader->exec->pedantic_hinting )
+        return error;
+
+      /* store drop-out mode in bits 5-7; set bit 2 also as a marker */
+      current_outline.tags[0] |=
+        ( loader->exec->GS.scan_type << 5 ) | FT_CURVE_TAG_HAS_SCANMODE;
+    }
+
+#endif
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    /* Save possibly modified glyph phantom points unless in v40 backward  */
+    /* compatibility mode, where no movement on the x axis means no reason */
+    /* to change bearings or advance widths.                               */
+    if ( !( driver->interpreter_version == TT_INTERPRETER_VERSION_40 &&
+            loader->exec->backward_compatibility ) )
+    {
+#endif
+      loader->pp1 = zone->cur[zone->n_points - 4];
+      loader->pp2 = zone->cur[zone->n_points - 3];
+      loader->pp3 = zone->cur[zone->n_points - 2];
+      loader->pp4 = zone->cur[zone->n_points - 1];
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    }
+#endif
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+    {
+      if ( loader->exec->sph_tweak_flags & SPH_TWEAK_DEEMBOLDEN )
+        FT_Outline_EmboldenXY( &loader->gloader->current.outline, -24, 0 );
+
+      else if ( loader->exec->sph_tweak_flags & SPH_TWEAK_EMBOLDEN )
+        FT_Outline_EmboldenXY( &loader->gloader->current.outline, 24, 0 );
+    }
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+    return FT_Err_Ok;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    TT_Process_Simple_Glyph                                            */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    Once a simple glyph has been loaded, it needs to be processed.     */
+  /*    Usually, this means scaling and hinting through bytecode           */
+  /*    interpretation.                                                    */
+  /*                                                                       */
+  static FT_Error
+  TT_Process_Simple_Glyph( TT_Loader  loader )
+  {
+    FT_GlyphLoader  gloader = loader->gloader;
+    FT_Error        error   = FT_Err_Ok;
+    FT_Outline*     outline;
+    FT_Int          n_points;
+
+
+    outline  = &gloader->current.outline;
+    n_points = outline->n_points;
+
+    /* set phantom points */
+
+    outline->points[n_points    ] = loader->pp1;
+    outline->points[n_points + 1] = loader->pp2;
+    outline->points[n_points + 2] = loader->pp3;
+    outline->points[n_points + 3] = loader->pp4;
+
+    outline->tags[n_points    ] = 0;
+    outline->tags[n_points + 1] = 0;
+    outline->tags[n_points + 2] = 0;
+    outline->tags[n_points + 3] = 0;
+
+    n_points += 4;
+
+    if ( IS_HINTED( loader->load_flags ) )
+    {
+      tt_prepare_zone( &loader->zone, &gloader->current, 0, 0 );
+
+      FT_ARRAY_COPY( loader->zone.orus, loader->zone.cur,
+                     loader->zone.n_points + 4 );
+    }
+
+    {
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+      TT_Face    face   = loader->face;
+      TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
+
+      FT_String*  family         = face->root.family_name;
+      FT_UInt     ppem           = loader->size->metrics->x_ppem;
+      FT_String*  style          = face->root.style_name;
+      FT_UInt     x_scale_factor = 1000;
+#endif
+
+      FT_Vector*  vec   = outline->points;
+      FT_Vector*  limit = outline->points + n_points;
+
+      FT_Fixed  x_scale = 0; /* pacify compiler */
+      FT_Fixed  y_scale = 0;
+
+      FT_Bool  do_scale = FALSE;
+
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+      {
+        /* scale, but only if enabled and only if TT hinting is being used */
+        if ( IS_HINTED( loader->load_flags ) )
+          x_scale_factor = sph_test_tweak_x_scaling( face,
+                                                     family,
+                                                     ppem,
+                                                     style,
+                                                     loader->glyph_index );
+        /* scale the glyph */
+        if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 ||
+             x_scale_factor != 1000                         )
+        {
+          x_scale = FT_MulDiv( loader->size->metrics->x_scale,
+                               (FT_Long)x_scale_factor, 1000 );
+          y_scale = loader->size->metrics->y_scale;
+
+          /* compensate for any scaling by de/emboldening; */
+          /* the amount was determined via experimentation */
+          if ( x_scale_factor != 1000 && ppem > 11 )
+            FT_Outline_EmboldenXY( outline,
+                                   FT_MulFix( 1280 * ppem,
+                                              1000 - x_scale_factor ),
+                                   0 );
+          do_scale = TRUE;
+        }
+      }
+      else
+
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+      {
+        /* scale the glyph */
+        if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
+        {
+          x_scale = loader->size->metrics->x_scale;
+          y_scale = loader->size->metrics->y_scale;
+
+          do_scale = TRUE;
+        }
+      }
+
+      if ( do_scale )
+      {
+        for ( ; vec < limit; vec++ )
+        {
+          vec->x = FT_MulFix( vec->x, x_scale );
+          vec->y = FT_MulFix( vec->y, y_scale );
+        }
+      }
+
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+      /* if we have a HVAR table, `pp1' and/or `pp2' are already adjusted */
+      if ( !( loader->face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) ||
+           !IS_HINTED( loader->load_flags )                                 )
+#endif
+      {
+        loader->pp1 = outline->points[n_points - 4];
+        loader->pp2 = outline->points[n_points - 3];
+      }
+
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+      /* if we have a VVAR table, `pp3' and/or `pp4' are already adjusted */
+      if ( !( loader->face->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) ||
+           !IS_HINTED( loader->load_flags )                                 )
+#endif
+      {
+        loader->pp3 = outline->points[n_points - 2];
+        loader->pp4 = outline->points[n_points - 1];
+      }
+    }
+
+    if ( IS_HINTED( loader->load_flags ) )
+    {
+      loader->zone.n_points += 4;
+
+      error = TT_Hint_Glyph( loader, 0 );
+    }
+
+    return error;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    TT_Process_Composite_Component                                     */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    Once a composite component has been loaded, it needs to be         */
+  /*    processed.  Usually, this means transforming and translating.      */
+  /*                                                                       */
+  static FT_Error
+  TT_Process_Composite_Component( TT_Loader    loader,
+                                  FT_SubGlyph  subglyph,
+                                  FT_UInt      start_point,
+                                  FT_UInt      num_base_points )
+  {
+    FT_GlyphLoader  gloader = loader->gloader;
+    FT_Outline      current;
+    FT_Bool         have_scale;
+    FT_Pos          x, y;
+
+
+    current.points   = gloader->base.outline.points +
+                         num_base_points;
+    current.n_points = gloader->base.outline.n_points -
+                         (short)num_base_points;
+
+    have_scale = FT_BOOL( subglyph->flags & ( WE_HAVE_A_SCALE     |
+                                              WE_HAVE_AN_XY_SCALE |
+                                              WE_HAVE_A_2X2       ) );
+
+    /* perform the transform required for this subglyph */
+    if ( have_scale )
+      FT_Outline_Transform( &current, &subglyph->transform );
+
+    /* get offset */
+    if ( !( subglyph->flags & ARGS_ARE_XY_VALUES ) )
+    {
+      FT_UInt     num_points = (FT_UInt)gloader->base.outline.n_points;
+      FT_UInt     k = (FT_UInt)subglyph->arg1;
+      FT_UInt     l = (FT_UInt)subglyph->arg2;
+      FT_Vector*  p1;
+      FT_Vector*  p2;
+
+
+      /* match l-th point of the newly loaded component to the k-th point */
+      /* of the previously loaded components.                             */
+
+      /* change to the point numbers used by our outline */
+      k += start_point;
+      l += num_base_points;
+      if ( k >= num_base_points ||
+           l >= num_points      )
+        return FT_THROW( Invalid_Composite );
+
+      p1 = gloader->base.outline.points + k;
+      p2 = gloader->base.outline.points + l;
+
+      x = p1->x - p2->x;
+      y = p1->y - p2->y;
+    }
+    else
+    {
+      x = subglyph->arg1;
+      y = subglyph->arg2;
+
+      if ( !x && !y )
+        return FT_Err_Ok;
+
+      /* Use a default value dependent on                                  */
+      /* TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED.  This is useful for old */
+      /* TT fonts which don't set the xxx_COMPONENT_OFFSET bit.            */
+
+      if ( have_scale &&
+#ifdef TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED
+           !( subglyph->flags & UNSCALED_COMPONENT_OFFSET ) )
+#else
+            ( subglyph->flags & SCALED_COMPONENT_OFFSET ) )
+#endif
+      {
+
+#if 0
+
+        /*******************************************************************/
+        /*                                                                 */
+        /* This algorithm is what Apple documents.  But it doesn't work.   */
+        /*                                                                 */
+        int  a = subglyph->transform.xx > 0 ?  subglyph->transform.xx
+                                            : -subglyph->transform.xx;
+        int  b = subglyph->transform.yx > 0 ?  subglyph->transform.yx
+                                            : -subglyph->transform.yx;
+        int  c = subglyph->transform.xy > 0 ?  subglyph->transform.xy
+                                            : -subglyph->transform.xy;
+        int  d = subglyph->transform.yy > 0 ?  subglyph->transform.yy
+                                            : -subglyph->transform.yy;
+        int  m = a > b ? a : b;
+        int  n = c > d ? c : d;
+
+
+        if ( a - b <= 33 && a - b >= -33 )
+          m *= 2;
+        if ( c - d <= 33 && c - d >= -33 )
+          n *= 2;
+        x = FT_MulFix( x, m );
+        y = FT_MulFix( y, n );
+
+#else /* 1 */
+
+        /*******************************************************************/
+        /*                                                                 */
+        /* This algorithm is a guess and works much better than the above. */
+        /*                                                                 */
+        FT_Fixed  mac_xscale = FT_Hypot( subglyph->transform.xx,
+                                         subglyph->transform.xy );
+        FT_Fixed  mac_yscale = FT_Hypot( subglyph->transform.yy,
+                                         subglyph->transform.yx );
+
+
+        x = FT_MulFix( x, mac_xscale );
+        y = FT_MulFix( y, mac_yscale );
+
+#endif /* 1 */
+
+      }
+
+      if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
+      {
+        FT_Fixed  x_scale = loader->size->metrics->x_scale;
+        FT_Fixed  y_scale = loader->size->metrics->y_scale;
+
+
+        x = FT_MulFix( x, x_scale );
+        y = FT_MulFix( y, y_scale );
+
+        if ( subglyph->flags & ROUND_XY_TO_GRID )
+        {
+          TT_Face    face   = loader->face;
+          TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
+
+
+          if ( IS_HINTED( loader->load_flags ) )
+          {
+            /*
+             * We round the horizontal offset only if there is hinting along
+             * the x axis; this corresponds to integer advance width values.
+             *
+             * Theoretically, a glyph's bytecode can toggle ClearType's
+             * `backward compatibility' mode, which would allow modification
+             * of the advance width.  In reality, however, applications
+             * neither allow nor expect modified advance widths if subpixel
+             * rendering is active.
+             *
+             */
+            if ( driver->interpreter_version == TT_INTERPRETER_VERSION_35 )
+              x = FT_PIX_ROUND( x );
+
+            y = FT_PIX_ROUND( y );
+          }
+        }
+      }
+    }
+
+    if ( x || y )
+      FT_Outline_Translate( &current, x, y );
+
+    return FT_Err_Ok;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    TT_Process_Composite_Glyph                                         */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    This is slightly different from TT_Process_Simple_Glyph, in that   */
+  /*    its sole purpose is to hint the glyph.  Thus this function is      */
+  /*    only available when bytecode interpreter is enabled.               */
+  /*                                                                       */
+  static FT_Error
+  TT_Process_Composite_Glyph( TT_Loader  loader,
+                              FT_UInt    start_point,
+                              FT_UInt    start_contour )
+  {
+    FT_Error     error;
+    FT_Outline*  outline;
+    FT_UInt      i;
+
+
+    outline = &loader->gloader->base.outline;
+
+    /* make room for phantom points */
+    error = FT_GLYPHLOADER_CHECK_POINTS( loader->gloader,
+                                         outline->n_points + 4,
+                                         0 );
+    if ( error )
+      return error;
+
+    outline->points[outline->n_points    ] = loader->pp1;
+    outline->points[outline->n_points + 1] = loader->pp2;
+    outline->points[outline->n_points + 2] = loader->pp3;
+    outline->points[outline->n_points + 3] = loader->pp4;
+
+    outline->tags[outline->n_points    ] = 0;
+    outline->tags[outline->n_points + 1] = 0;
+    outline->tags[outline->n_points + 2] = 0;
+    outline->tags[outline->n_points + 3] = 0;
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+    {
+      FT_Stream  stream = loader->stream;
+      FT_UShort  n_ins, max_ins;
+      FT_ULong   tmp;
+
+
+      /* TT_Load_Composite_Glyph only gives us the offset of instructions */
+      /* so we read them here                                             */
+      if ( FT_STREAM_SEEK( loader->ins_pos ) ||
+           FT_READ_USHORT( n_ins )           )
+        return error;
+
+      FT_TRACE5(( "  Instructions size = %d\n", n_ins ));
+
+      /* check it */
+      max_ins = loader->face->max_profile.maxSizeOfInstructions;
+      if ( n_ins > max_ins )
+      {
+        /* don't trust `maxSizeOfInstructions'; */
+        /* only do a rough safety check         */
+        if ( (FT_Int)n_ins > loader->byte_len )
+        {
+          FT_TRACE1(( "TT_Process_Composite_Glyph:"
+                      " too many instructions (%d) for glyph with length %d\n",
+                      n_ins, loader->byte_len ));
+          return FT_THROW( Too_Many_Hints );
+        }
+
+        tmp   = loader->exec->glyphSize;
+        error = Update_Max( loader->exec->memory,
+                            &tmp,
+                            sizeof ( FT_Byte ),
+                            (void*)&loader->exec->glyphIns,
+                            n_ins );
+
+        loader->exec->glyphSize = (FT_UShort)tmp;
+        if ( error )
+          return error;
+      }
+      else if ( n_ins == 0 )
+        return FT_Err_Ok;
+
+      if ( FT_STREAM_READ( loader->exec->glyphIns, n_ins ) )
+        return error;
+
+      loader->glyph->control_data = loader->exec->glyphIns;
+      loader->glyph->control_len  = n_ins;
+    }
+
+#endif
+
+    tt_prepare_zone( &loader->zone, &loader->gloader->base,
+                     start_point, start_contour );
+
+    /* Some points are likely touched during execution of  */
+    /* instructions on components.  So let's untouch them. */
+    for ( i = 0; i < loader->zone.n_points; i++ )
+      loader->zone.tags[i] &= ~FT_CURVE_TAG_TOUCH_BOTH;
+
+    loader->zone.n_points += 4;
+
+    return TT_Hint_Glyph( loader, 1 );
+  }
+
+
+  /*
+   * Calculate the phantom points
+   *
+   * Defining the right side bearing (rsb) as
+   *
+   *   rsb = aw - (lsb + xmax - xmin)
+   *
+   * (with `aw' the advance width, `lsb' the left side bearing, and `xmin'
+   * and `xmax' the glyph's minimum and maximum x value), the OpenType
+   * specification defines the initial position of horizontal phantom points
+   * as
+   *
+   *   pp1 = (round(xmin - lsb), 0)      ,
+   *   pp2 = (round(pp1 + aw), 0)        .
+   *
+   * Note that the rounding to the grid (in the device space) is not
+   * documented currently in the specification.
+   *
+   * However, the specification lacks the precise definition of vertical
+   * phantom points.  Greg Hitchcock provided the following explanation.
+   *
+   * - a `vmtx' table is present
+   *
+   *   For any glyph, the minimum and maximum y values (`ymin' and `ymax')
+   *   are given in the `glyf' table, the top side bearing (tsb) and advance
+   *   height (ah) are given in the `vmtx' table.  The bottom side bearing
+   *   (bsb) is then calculated as
+   *
+   *     bsb = ah - (tsb + ymax - ymin)       ,
+   *
+   *   and the initial position of vertical phantom points is
+   *
+   *     pp3 = (x, round(ymax + tsb))       ,
+   *     pp4 = (x, round(pp3 - ah))         .
+   *
+   *   See below for value `x'.
+   *
+   * - no `vmtx' table in the font
+   *
+   *   If there is an `OS/2' table, we set
+   *
+   *     DefaultAscender = sTypoAscender       ,
+   *     DefaultDescender = sTypoDescender     ,
+   *
+   *   otherwise we use data from the `hhea' table:
+   *
+   *     DefaultAscender = Ascender         ,
+   *     DefaultDescender = Descender       .
+   *
+   *   With these two variables we can now set
+   *
+   *     ah = DefaultAscender - sDefaultDescender    ,
+   *     tsb = DefaultAscender - yMax                ,
+   *
+   *   and proceed as if a `vmtx' table was present.
+   *
+   * Usually we have
+   *
+   *   x = aw / 2      ,                                                (1)
+   *
+   * but there is one compatibility case where it can be set to
+   *
+   *   x = -DefaultDescender -
+   *         ((DefaultAscender - DefaultDescender - aw) / 2)     .      (2)
+   *
+   * and another one with
+   *
+   *   x = 0     .                                                      (3)
+   *
+   * In Windows, the history of those values is quite complicated,
+   * depending on the hinting engine (that is, the graphics framework).
+   *
+   *   framework        from                 to       formula
+   *  ----------------------------------------------------------
+   *    GDI       Windows 98               current      (1)
+   *              (Windows 2000 for NT)
+   *    GDI+      Windows XP               Windows 7    (2)
+   *    GDI+      Windows 8                current      (3)
+   *    DWrite    Windows 7                current      (3)
+   *
+   * For simplicity, FreeType uses (1) for grayscale subpixel hinting and
+   * (3) for everything else.
+   *
+   */
+  static void
+  tt_loader_set_pp( TT_Loader  loader )
+  {
+    FT_Bool  subpixel_hinting = 0;
+    FT_Bool  grayscale        = 0;
+    FT_Bool  use_aw_2         = 0;
+
+#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
+    TT_Driver driver = (TT_Driver)FT_FACE_DRIVER( loader->face );
+#endif
+
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+    {
+      subpixel_hinting = loader->exec ? loader->exec->subpixel_hinting
+                                      : 0;
+      grayscale        = loader->exec ? loader->exec->grayscale
+                                      : 0;
+    }
+#endif
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_40 )
+    {
+      subpixel_hinting = loader->exec ? loader->exec->subpixel_hinting_lean
+                                      : 0;
+      grayscale        = loader->exec ? loader->exec->grayscale_cleartype
+                                      : 0;
+    }
+#endif
+
+    use_aw_2 = (FT_Bool)( subpixel_hinting && grayscale );
+
+    loader->pp1.x = loader->bbox.xMin - loader->left_bearing;
+    loader->pp1.y = 0;
+    loader->pp2.x = loader->pp1.x + loader->advance;
+    loader->pp2.y = 0;
+
+    loader->pp3.x = use_aw_2 ? loader->advance / 2 : 0;
+    loader->pp3.y = loader->bbox.yMax + loader->top_bearing;
+    loader->pp4.x = use_aw_2 ? loader->advance / 2 : 0;
+    loader->pp4.y = loader->pp3.y - loader->vadvance;
+  }
+
+
+  /* a utility function to retrieve i-th node from given FT_List */
+  static FT_ListNode
+  ft_list_get_node_at( FT_List  list,
+                       FT_UInt  idx )
+  {
+    FT_ListNode  cur;
+
+
+    if ( !list )
+      return NULL;
+
+    for ( cur = list->head; cur; cur = cur->next )
+    {
+      if ( !idx )
+        return cur;
+
+      idx--;
+    }
+
+    return NULL;
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    load_truetype_glyph                                                */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    Loads a given truetype glyph.  Handles composites and uses a       */
+  /*    TT_Loader object.                                                  */
+  /*                                                                       */
+  static FT_Error
+  load_truetype_glyph( TT_Loader  loader,
+                       FT_UInt    glyph_index,
+                       FT_UInt    recurse_count,
+                       FT_Bool    header_only )
+  {
+    FT_Error        error        = FT_Err_Ok;
+    FT_Fixed        x_scale, y_scale;
+    FT_ULong        offset;
+    TT_Face         face         = loader->face;
+    FT_GlyphLoader  gloader      = loader->gloader;
+    FT_Bool         opened_frame = 0;
+
+
+    /* some fonts have an incorrect value of `maxComponentDepth' */
+    if ( recurse_count > face->max_profile.maxComponentDepth )
+    {
+      FT_TRACE1(( "load_truetype_glyph: maxComponentDepth set to %d\n",
+                  recurse_count ));
+      face->max_profile.maxComponentDepth = (FT_UShort)recurse_count;
+    }
+
+#ifndef FT_CONFIG_OPTION_INCREMENTAL
+    /* check glyph index */
+    if ( glyph_index >= (FT_UInt)face->root.num_glyphs )
+    {
+      error = FT_THROW( Invalid_Glyph_Index );
+      goto Exit;
+    }
+#endif
+
+    loader->glyph_index = glyph_index;
+
+    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
+    {
+      x_scale = loader->size->metrics->x_scale;
+      y_scale = loader->size->metrics->y_scale;
+    }
+    else
+    {
+      x_scale = 0x10000L;
+      y_scale = 0x10000L;
+    }
+
+    /* Set `offset' to the start of the glyph relative to the start of */
+    /* the `glyf' table, and `byte_len' to the length of the glyph in  */
+    /* bytes.                                                          */
+
+#ifdef FT_CONFIG_OPTION_INCREMENTAL
+
+    /* If we are loading glyph data via the incremental interface, set */
+    /* the loader stream to a memory stream reading the data returned  */
+    /* by the interface.                                               */
+    if ( face->root.internal->incremental_interface )
+    {
+      error = face->root.internal->incremental_interface->funcs->get_glyph_data(
+                face->root.internal->incremental_interface->object,
+                glyph_index, &glyph_data );
+      if ( error )
+        goto Exit;
+
+      glyph_data_loaded = 1;
+      offset            = 0;
+      loader->byte_len  = glyph_data.length;
+
+      FT_ZERO( &inc_stream );
+      FT_Stream_OpenMemory( &inc_stream,
+                            glyph_data.pointer,
+                            (FT_ULong)glyph_data.length );
+
+      loader->stream = &inc_stream;
+    }
+    else
+
+#endif /* FT_CONFIG_OPTION_INCREMENTAL */
+
+      offset = tt_face_get_location( face, glyph_index,
+                                     (FT_UInt*)&loader->byte_len );
+
+    if ( loader->byte_len > 0 )
+    {
+#ifdef FT_CONFIG_OPTION_INCREMENTAL
+      /* for the incremental interface, `glyf_offset' is always zero */
+      if ( !face->glyf_offset                          &&
+           !face->root.internal->incremental_interface )
+#else
+      if ( !face->glyf_offset )
+#endif /* FT_CONFIG_OPTION_INCREMENTAL */
+      {
+        FT_TRACE2(( "no `glyf' table but non-zero `loca' entry\n" ));
+        error = FT_THROW( Invalid_Table );
+        goto Exit;
+      }
+
+      error = face->access_glyph_frame( loader, glyph_index,
+                                        face->glyf_offset + offset,
+                                        (FT_UInt)loader->byte_len );
+      if ( error )
+        goto Exit;
+
+      opened_frame = 1;
+
+      /* read glyph header first */
+      error = face->read_glyph_header( loader );
+      if ( error )
+        goto Exit;
+
+      /* the metrics must be computed after loading the glyph header */
+      /* since we need the glyph's `yMax' value in case the vertical */
+      /* metrics must be emulated                                    */
+      error = tt_get_metrics( loader, glyph_index );
+      if ( error )
+        goto Exit;
+
+      if ( header_only )
+        goto Exit;
+    }
+
+    if ( loader->byte_len == 0 || loader->n_contours == 0 )
+    {
+      loader->bbox.xMin = 0;
+      loader->bbox.xMax = 0;
+      loader->bbox.yMin = 0;
+      loader->bbox.yMax = 0;
+
+      error = tt_get_metrics( loader, glyph_index );
+      if ( error )
+        goto Exit;
+
+      if ( header_only )
+        goto Exit;
+
+      /* must initialize points before (possibly) overriding */
+      /* glyph metrics from the incremental interface        */
+      tt_loader_set_pp( loader );
+
+      /* scale phantom points, if necessary; */
+      /* they get rounded in `TT_Hint_Glyph' */
+      if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
+      {
+        loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
+        loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
+        /* pp1.y and pp2.y are always zero */
+
+        loader->pp3.x = FT_MulFix( loader->pp3.x, x_scale );
+        loader->pp3.y = FT_MulFix( loader->pp3.y, y_scale );
+        loader->pp4.x = FT_MulFix( loader->pp4.x, x_scale );
+        loader->pp4.y = FT_MulFix( loader->pp4.y, y_scale );
+      }
+
+      error = FT_Err_Ok;
+      goto Exit;
+    }
+
+    /* must initialize phantom points before (possibly) overriding */
+    /* glyph metrics from the incremental interface                */
+    tt_loader_set_pp( loader );
+
+    /***********************************************************************/
+    /***********************************************************************/
+    /***********************************************************************/
+
+    /* if it is a simple glyph, load it */
+
+    if ( loader->n_contours > 0 )
+    {
+      error = face->read_simple_glyph( loader );
+      if ( error )
+        goto Exit;
+
+      /* all data have been read */
+      face->forget_glyph_frame( loader );
+      opened_frame = 0;
+
+      error = TT_Process_Simple_Glyph( loader );
+      if ( error )
+        goto Exit;
+
+      FT_GlyphLoader_Add( gloader );
+    }
+
+    /***********************************************************************/
+    /***********************************************************************/
+    /***********************************************************************/
+
+    /* otherwise, load a composite! */
+    else if ( loader->n_contours < 0 )
+    {
+      FT_Memory  memory = face->root.memory;
+
+      FT_UInt   start_point;
+      FT_UInt   start_contour;
+      FT_ULong  ins_pos;  /* position of composite instructions, if any */
+
+      FT_ListNode  node, node2;
+
+
+      /* normalize the `n_contours' value */
+      loader->n_contours = -1;
+
+      /*
+       * We store the glyph index directly in the `node->data' pointer,
+       * following the glib solution (cf. macro `GUINT_TO_POINTER') with a
+       * double cast to make this portable.  Note, however, that this needs
+       * pointers with a width of at least 32 bits.
+       */
+
+
+      /* clear the nodes filled by sibling chains */
+      node = ft_list_get_node_at( &loader->composites, recurse_count );
+      for ( node2 = node; node2; node2 = node2->next )
+        node2->data = (void*)FT_ULONG_MAX;
+
+      /* check whether we already have a composite glyph with this index */
+      if ( FT_List_Find( &loader->composites,
+                         FT_UINT_TO_POINTER( glyph_index ) ) )
+      {
+        FT_TRACE1(( "TT_Load_Composite_Glyph:"
+                    " infinite recursion detected\n" ));
+        error = FT_THROW( Invalid_Composite );
+        goto Exit;
+      }
+
+      else if ( node )
+        node->data = FT_UINT_TO_POINTER( glyph_index );
+
+      else
+      {
+        if ( FT_NEW( node ) )
+          goto Exit;
+        node->data = FT_UINT_TO_POINTER( glyph_index );
+        FT_List_Add( &loader->composites, node );
+      }
+
+      start_point   = (FT_UInt)gloader->base.outline.n_points;
+      start_contour = (FT_UInt)gloader->base.outline.n_contours;
+
+      /* for each subglyph, read composite header */
+      error = face->read_composite_glyph( loader );
+      if ( error )
+        goto Exit;
+
+      /* store the offset of instructions */
+      ins_pos = loader->ins_pos;
+
+      /* all data we need are read */
+      face->forget_glyph_frame( loader );
+      opened_frame = 0;
+
+      /* scale phantom points, if necessary; */
+      /* they get rounded in `TT_Hint_Glyph' */
+      if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
+      {
+        loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
+        loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
+        /* pp1.y and pp2.y are always zero */
+
+        loader->pp3.x = FT_MulFix( loader->pp3.x, x_scale );
+        loader->pp3.y = FT_MulFix( loader->pp3.y, y_scale );
+        loader->pp4.x = FT_MulFix( loader->pp4.x, x_scale );
+        loader->pp4.y = FT_MulFix( loader->pp4.y, y_scale );
+      }
+
+      /* if the flag FT_LOAD_NO_RECURSE is set, we return the subglyph */
+      /* `as is' in the glyph slot (the client application will be     */
+      /* responsible for interpreting these data)...                   */
+      if ( loader->load_flags & FT_LOAD_NO_RECURSE )
+      {
+        FT_GlyphLoader_Add( gloader );
+        loader->glyph->format = FT_GLYPH_FORMAT_COMPOSITE;
+
+        goto Exit;
+      }
+
+      /*********************************************************************/
+      /*********************************************************************/
+      /*********************************************************************/
+
+      {
+        FT_UInt      n, num_base_points;
+        FT_SubGlyph  subglyph       = NULL;
+
+        FT_UInt      num_points     = start_point;
+        FT_UInt      num_subglyphs  = gloader->current.num_subglyphs;
+        FT_UInt      num_base_subgs = gloader->base.num_subglyphs;
+
+        FT_Stream    old_stream     = loader->stream;
+        FT_Int       old_byte_len   = loader->byte_len;
+
+
+        FT_GlyphLoader_Add( gloader );
+
+        /* read each subglyph independently */
+        for ( n = 0; n < num_subglyphs; n++ )
+        {
+          FT_Vector  pp[4];
+
+          FT_Int  linear_hadvance;
+          FT_Int  linear_vadvance;
+
+
+          /* Each time we call load_truetype_glyph in this loop, the   */
+          /* value of `gloader.base.subglyphs' can change due to table */
+          /* reallocations.  We thus need to recompute the subglyph    */
+          /* pointer on each iteration.                                */
+          subglyph = gloader->base.subglyphs + num_base_subgs + n;
+
+          pp[0] = loader->pp1;
+          pp[1] = loader->pp2;
+          pp[2] = loader->pp3;
+          pp[3] = loader->pp4;
+
+          linear_hadvance = loader->linear;
+          linear_vadvance = loader->vadvance;
+
+          num_base_points = (FT_UInt)gloader->base.outline.n_points;
+
+          error = load_truetype_glyph( loader,
+                                       (FT_UInt)subglyph->index,
+                                       recurse_count + 1,
+                                       FALSE );
+          if ( error )
+            goto Exit;
+
+          /* restore subglyph pointer */
+          subglyph = gloader->base.subglyphs + num_base_subgs + n;
+
+          /* restore phantom points if necessary */
+          if ( !( subglyph->flags & USE_MY_METRICS ) )
+          {
+            loader->pp1 = pp[0];
+            loader->pp2 = pp[1];
+            loader->pp3 = pp[2];
+            loader->pp4 = pp[3];
+
+            loader->linear   = linear_hadvance;
+            loader->vadvance = linear_vadvance;
+          }
+
+          num_points = (FT_UInt)gloader->base.outline.n_points;
+
+          if ( num_points == num_base_points )
+            continue;
+
+          /* gloader->base.outline consists of three parts:               */
+          /* 0 -(1)-> start_point -(2)-> num_base_points -(3)-> n_points. */
+          /*                                                              */
+          /* (1): exists from the beginning                               */
+          /* (2): components that have been loaded so far                 */
+          /* (3): the newly loaded component                              */
+          error = TT_Process_Composite_Component( loader,
+                                                  subglyph,
+                                                  start_point,
+                                                  num_base_points );
+          if ( error )
+            goto Exit;
+        }
+
+        loader->stream   = old_stream;
+        loader->byte_len = old_byte_len;
+
+        /* process the glyph */
+        loader->ins_pos = ins_pos;
+        if ( IS_HINTED( loader->load_flags ) &&
+#ifdef TT_USE_BYTECODE_INTERPRETER
+             subglyph->flags & WE_HAVE_INSTR &&
+#endif
+             num_points > start_point )
+        {
+          error = TT_Process_Composite_Glyph( loader,
+                                              start_point,
+                                              start_contour );
+          if ( error )
+            goto Exit;
+        }
+      }
+    }
+
+    /***********************************************************************/
+    /***********************************************************************/
+    /***********************************************************************/
+
+  Exit:
+
+    if ( opened_frame )
+      face->forget_glyph_frame( loader );
+
+    return error;
+  }
+
+
+  static FT_Error
+  compute_glyph_metrics( TT_Loader  loader,
+                         FT_UInt    glyph_index )
+  {
+    TT_Face    face   = loader->face;
+#if defined TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY || \
+    defined TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
+#endif
+
+    FT_BBox       bbox;
+    FT_Fixed      y_scale;
+    TT_GlyphSlot  glyph = loader->glyph;
+    TT_Size       size  = loader->size;
+
+
+    y_scale = 0x10000L;
+    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
+      y_scale = size->metrics->y_scale;
+
+    if ( glyph->format != FT_GLYPH_FORMAT_COMPOSITE )
+      FT_Outline_Get_CBox( &glyph->outline, &bbox );
+    else
+      bbox = loader->bbox;
+
+    /* get the device-independent horizontal advance; it is scaled later */
+    /* by the base layer.                                                */
+    glyph->linearHoriAdvance = loader->linear;
+
+    glyph->metrics.horiBearingX = bbox.xMin;
+    glyph->metrics.horiBearingY = bbox.yMax;
+    glyph->metrics.horiAdvance  = loader->pp2.x - loader->pp1.x;
+
+    /* Adjust advance width to the value contained in the hdmx table   */
+    /* unless FT_LOAD_COMPUTE_METRICS is set or backward compatibility */
+    /* mode of the v40 interpreter is active.  See `ttinterp.h' for    */
+    /* details on backward compatibility mode.                         */
+    if (
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+         !( driver->interpreter_version == TT_INTERPRETER_VERSION_40  &&
+            ( loader->exec && loader->exec->backward_compatibility  ) ) &&
+#endif
+         !face->postscript.isFixedPitch                                 &&
+         IS_HINTED( loader->load_flags )                                &&
+         !( loader->load_flags & FT_LOAD_COMPUTE_METRICS )              )
+    {
+      FT_Byte*  widthp;
+
+
+      widthp = tt_face_get_device_metrics( face,
+                                           size->metrics->x_ppem,
+                                           glyph_index );
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+      {
+        FT_Bool  ignore_x_mode;
+
+
+        ignore_x_mode = FT_BOOL( FT_LOAD_TARGET_MODE( loader->load_flags ) !=
+                                 FT_RENDER_MODE_MONO );
+
+        if ( widthp                                                   &&
+             ( ( ignore_x_mode && loader->exec->compatible_widths ) ||
+                !ignore_x_mode                                      ||
+                SPH_OPTION_BITMAP_WIDTHS                            ) )
+          glyph->metrics.horiAdvance = *widthp * 64;
+      }
+      else
+
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+      {
+        if ( widthp )
+          glyph->metrics.horiAdvance = *widthp * 64;
+      }
+    }
+
+    /* set glyph dimensions */
+    glyph->metrics.width  = SUB_LONG( bbox.xMax, bbox.xMin );
+    glyph->metrics.height = SUB_LONG( bbox.yMax, bbox.yMin );
+
+    /* Now take care of vertical metrics.  In the case where there is */
+    /* no vertical information within the font (relatively common),   */
+    /* create some metrics manually                                   */
+    {
+      FT_Pos  top;      /* scaled vertical top side bearing  */
+      FT_Pos  advance;  /* scaled vertical advance height    */
+
+
+      /* Get the unscaled top bearing and advance height. */
+      if ( face->vertical_info                   &&
+           face->vertical.number_Of_VMetrics > 0 )
+      {
+        top = (FT_Short)FT_DivFix( loader->pp3.y - bbox.yMax,
+                                   y_scale );
+
+        if ( loader->pp3.y <= loader->pp4.y )
+          advance = 0;
+        else
+          advance = (FT_UShort)FT_DivFix( loader->pp3.y - loader->pp4.y,
+                                          y_scale );
+      }
+      else
+      {
+        FT_Pos  height;
+
+
+        /* XXX Compute top side bearing and advance height in  */
+        /*     Get_VMetrics instead of here.                   */
+
+        /* NOTE: The OS/2 values are the only `portable' ones, */
+        /*       which is why we use them, if there is an OS/2 */
+        /*       table in the font.  Otherwise, we use the     */
+        /*       values defined in the horizontal header.      */
+
+        height = (FT_Short)FT_DivFix( SUB_LONG( bbox.yMax,
+                                                bbox.yMin ),
+                                      y_scale );
+        if ( face->os2.version != 0xFFFFU )
+          advance = (FT_Pos)( face->os2.sTypoAscender -
+                              face->os2.sTypoDescender );
+        else
+          advance = (FT_Pos)( face->horizontal.Ascender -
+                              face->horizontal.Descender );
+
+        top = ( advance - height ) / 2;
+      }
+
+      glyph->linearVertAdvance = advance;
+
+      /* scale the metrics */
+      if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
+      {
+        top     = FT_MulFix( top,     y_scale );
+        advance = FT_MulFix( advance, y_scale );
+      }
+
+      /* XXX: for now, we have no better algorithm for the lsb, but it */
+      /*      should work fine.                                        */
+      /*                                                               */
+      glyph->metrics.vertBearingX = glyph->metrics.horiBearingX -
+                                      glyph->metrics.horiAdvance / 2;
+      glyph->metrics.vertBearingY = top;
+      glyph->metrics.vertAdvance  = advance;
+    }
+
+    return 0;
+  }
+
+
+#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
+
+  static FT_Error
+  load_sbit_image( TT_Size       size,
+                   TT_GlyphSlot  glyph,
+                   FT_UInt       glyph_index,
+                   FT_Int32      load_flags )
+  {
+    TT_Face             face;
+    SFNT_Service        sfnt;
+    FT_Stream           stream;
+    FT_Error            error;
+    TT_SBit_MetricsRec  sbit_metrics;
+
+
+    face   = (TT_Face)glyph->face;
+    sfnt   = (SFNT_Service)face->sfnt;
+    stream = face->root.stream;
+
+    error = sfnt->load_sbit_image( face,
+                                   size->strike_index,
+                                   glyph_index,
+                                   (FT_UInt)load_flags,
+                                   stream,
+                                   &glyph->bitmap,
+                                   &sbit_metrics );
+    if ( !error )
+    {
+      glyph->outline.n_points   = 0;
+      glyph->outline.n_contours = 0;
+
+      glyph->metrics.width  = (FT_Pos)sbit_metrics.width  * 64;
+      glyph->metrics.height = (FT_Pos)sbit_metrics.height * 64;
+
+      glyph->metrics.horiBearingX = (FT_Pos)sbit_metrics.horiBearingX * 64;
+      glyph->metrics.horiBearingY = (FT_Pos)sbit_metrics.horiBearingY * 64;
+      glyph->metrics.horiAdvance  = (FT_Pos)sbit_metrics.horiAdvance  * 64;
+
+      glyph->metrics.vertBearingX = (FT_Pos)sbit_metrics.vertBearingX * 64;
+      glyph->metrics.vertBearingY = (FT_Pos)sbit_metrics.vertBearingY * 64;
+      glyph->metrics.vertAdvance  = (FT_Pos)sbit_metrics.vertAdvance  * 64;
+
+      glyph->format = FT_GLYPH_FORMAT_BITMAP;
+
+      if ( load_flags & FT_LOAD_VERTICAL_LAYOUT )
+      {
+        glyph->bitmap_left = sbit_metrics.vertBearingX;
+        glyph->bitmap_top  = sbit_metrics.vertBearingY;
+      }
+      else
+      {
+        glyph->bitmap_left = sbit_metrics.horiBearingX;
+        glyph->bitmap_top  = sbit_metrics.horiBearingY;
+      }
+    }
+
+    return error;
+  }
+
+#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
+
+
+  static FT_Error
+  tt_loader_init( TT_Loader     loader,
+                  TT_Size       size,
+                  TT_GlyphSlot  glyph,
+                  FT_Int32      load_flags,
+                  FT_Bool       glyf_table_only )
+  {
+    TT_Face    face;
+    FT_Stream  stream;
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+    FT_Error   error;
+    FT_Bool    pedantic = FT_BOOL( load_flags & FT_LOAD_PEDANTIC );
+#if defined TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY || \
+    defined TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( (TT_Face)glyph->face );
+#endif
+#endif
+
+
+    face   = (TT_Face)glyph->face;
+    stream = face->root.stream;
+
+    FT_ZERO( loader );
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+    /* load execution context */
+    if ( IS_HINTED( load_flags ) && !glyf_table_only )
+    {
+      TT_ExecContext  exec;
+      FT_Bool         grayscale = TRUE;
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+      FT_Bool         subpixel_hinting_lean;
+      FT_Bool         grayscale_cleartype;
+#endif
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+      FT_Bool  subpixel_hinting = FALSE;
+
+#if 0
+      /* not used yet */
+      FT_Bool  compatible_widths;
+      FT_Bool  symmetrical_smoothing;
+      FT_Bool  bgr;
+      FT_Bool  vertical_lcd;
+      FT_Bool  subpixel_positioned;
+      FT_Bool  gray_cleartype;
+#endif
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+      FT_Bool  reexecute = FALSE;
+
+
+      if ( size->bytecode_ready < 0 || size->cvt_ready < 0 )
+      {
+        error = tt_size_ready_bytecode( size, pedantic );
+        if ( error )
+          return error;
+      }
+      else if ( size->bytecode_ready )
+        return size->bytecode_ready;
+      else if ( size->cvt_ready )
+        return size->cvt_ready;
+
+      /* query new execution context */
+      exec = size->context;
+      if ( !exec )
+        return FT_THROW( Could_Not_Find_Context );
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_40 )
+      {
+        subpixel_hinting_lean =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   FT_RENDER_MODE_MONO               );
+        grayscale_cleartype = FT_BOOL( subpixel_hinting_lean );
+        exec->vertical_lcd_lean = FALSE;
+      }
+      else
+      {
+        subpixel_hinting_lean   = FALSE;
+        grayscale_cleartype     = FALSE;
+        exec->vertical_lcd_lean = FALSE;
+      }
+#endif
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+      {
+        subpixel_hinting = FT_BOOL( ( FT_LOAD_TARGET_MODE( load_flags ) !=
+                                      FT_RENDER_MODE_MONO               )  &&
+                                    SPH_OPTION_SET_SUBPIXEL                );
+
+        if ( subpixel_hinting )
+          grayscale = FALSE;
+        else if ( SPH_OPTION_SET_GRAYSCALE )
+        {
+          grayscale        = TRUE;
+          subpixel_hinting = FALSE;
+        }
+        else
+          grayscale = FALSE;
+
+        if ( FT_IS_TRICKY( glyph->face ) )
+          subpixel_hinting = FALSE;
+
+        exec->ignore_x_mode      = subpixel_hinting || grayscale;
+        exec->rasterizer_version = SPH_OPTION_SET_RASTERIZER_VERSION;
+        if ( exec->sph_tweak_flags & SPH_TWEAK_RASTERIZER_35 )
+          exec->rasterizer_version = TT_INTERPRETER_VERSION_35;
+
+#if 1
+        exec->compatible_widths     = SPH_OPTION_SET_COMPATIBLE_WIDTHS;
+        exec->symmetrical_smoothing = TRUE;
+        exec->bgr                   = FALSE;
+        exec->vertical_lcd          = FALSE;
+        exec->subpixel_positioned   = TRUE;
+        exec->gray_cleartype        = FALSE;
+#else /* 0 */
+        exec->compatible_widths =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_COMPATIBLE_WIDTHS );
+        exec->symmetrical_smoothing =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_SYMMETRICAL_SMOOTHING );
+        exec->bgr =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_BGR );
+        exec->vertical_lcd =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_VERTICAL_LCD );
+        exec->subpixel_positioned =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_SUBPIXEL_POSITIONED );
+        exec->gray_cleartype =
+          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                   TT_LOAD_GRAY_CLEARTYPE );
+#endif /* 0 */
+
+      }
+      else
+
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_40 )
+        grayscale = FT_BOOL( !subpixel_hinting_lean               &&
+                             FT_LOAD_TARGET_MODE( load_flags ) !=
+                               FT_RENDER_MODE_MONO                );
+      else
+#endif
+        grayscale = FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
+                               FT_RENDER_MODE_MONO             );
+
+      error = TT_Load_Context( exec, face, size );
+      if ( error )
+        return error;
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
+      {
+        /* a change from mono to subpixel rendering (and vice versa) */
+        /* requires a re-execution of the CVT program                */
+        if ( subpixel_hinting != exec->subpixel_hinting )
+        {
+          FT_TRACE4(( "tt_loader_init: subpixel hinting change,"
+                      " re-executing `prep' table\n" ));
+
+          exec->subpixel_hinting = subpixel_hinting;
+          reexecute              = TRUE;
+        }
+
+        /* a change from mono to grayscale rendering (and vice versa) */
+        /* requires a re-execution of the CVT program                 */
+        if ( grayscale != exec->grayscale )
+        {
+          FT_TRACE4(( "tt_loader_init: grayscale hinting change,"
+                      " re-executing `prep' table\n" ));
+
+          exec->grayscale = grayscale;
+          reexecute       = TRUE;
+        }
+      }
+      else
+
+#endif /* TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY */
+
+      {
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL
+        if ( driver->interpreter_version == TT_INTERPRETER_VERSION_40 )
+        {
+          /* a change from mono to subpixel rendering (and vice versa) */
+          /* requires a re-execution of the CVT program                */
+          if ( subpixel_hinting_lean != exec->subpixel_hinting_lean )
+          {
+            FT_TRACE4(( "tt_loader_init: subpixel hinting change,"
+                        " re-executing `prep' table\n" ));
+
+            exec->subpixel_hinting_lean = subpixel_hinting_lean;
+            reexecute                   = TRUE;
+          }
+
+          /* a change from colored to grayscale subpixel rendering (and */
+          /* vice versa) requires a re-execution of the CVT program     */
+          if ( grayscale_cleartype != exec->grayscale_cleartype )
+          {
+            FT_TRACE4(( "tt_loader_init: grayscale subpixel hinting change,"
+                        " re-executing `prep' table\n" ));
+
+            exec->grayscale_cleartype = grayscale_cleartype;
+            reexecute                 = TRUE;
+          }
+        }
+#endif
+
+        /* a change from mono to grayscale rendering (and vice versa) */
+        /* requires a re-execution of the CVT program                 */
+        if ( grayscale != exec->grayscale )
+        {
+          FT_TRACE4(( "tt_loader_init: grayscale hinting change,"
+                      " re-executing `prep' table\n" ));
+
+          exec->grayscale = grayscale;
+          reexecute       = TRUE;
+        }
+      }
+
+      if ( reexecute )
+      {
+        FT_UInt  i;
+
+
+        for ( i = 0; i < size->cvt_size; i++ )
+          size->cvt[i] = FT_MulFix( face->cvt[i], size->ttmetrics.scale );
+        error = tt_size_run_prep( size, pedantic );
+        if ( error )
+          return error;
+      }
+
+      /* check whether the cvt program has disabled hinting */
+      if ( exec->GS.instruct_control & 1 )
+        load_flags |= FT_LOAD_NO_HINTING;
+
+      /* load default graphics state -- if needed */
+      if ( exec->GS.instruct_control & 2 )
+        exec->GS = tt_default_graphics_state;
+
+#ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY
+      /* check whether we have a font hinted for ClearType --           */
+      /* note that this flag can also be modified in a glyph's bytecode */
+      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 &&
+           exec->GS.instruct_control & 4                            )
+        exec->ignore_x_mode = 0;
+#endif
+
+      exec->pedantic_hinting = FT_BOOL( load_flags & FT_LOAD_PEDANTIC );
+      loader->exec = exec;
+      loader->instructions = exec->glyphIns;
+    }
+
+#endif /* TT_USE_BYTECODE_INTERPRETER */
+
+    /* get face's glyph loader */
+    if ( !glyf_table_only )
+    {
+      FT_GlyphLoader  gloader = glyph->internal->loader;
+
+
+      FT_GlyphLoader_Rewind( gloader );
+      loader->gloader = gloader;
+    }
+
+    loader->load_flags = (FT_ULong)load_flags;
+
+    loader->face   = face;
+    loader->size   = size;
+    loader->glyph  = (FT_GlyphSlot)glyph;
+    loader->stream = stream;
+
+    loader->composites.head = NULL;
+    loader->composites.tail = NULL;
+
+    return FT_Err_Ok;
+  }
+
+
+  static void
+  tt_loader_done( TT_Loader  loader )
+  {
+    FT_List_Finalize( &loader->composites,
+                      NULL,
+                      loader->face->root.memory,
+                      NULL );
+  }
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    TT_Load_Glyph                                                      */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    A function used to load a single glyph within a given glyph slot,  */
+  /*    for a given size.                                                  */
+  /*                                                                       */
+  /* <Input>                                                               */
+  /*    glyph       :: A handle to a target slot object where the glyph    */
+  /*                   will be loaded.                                     */
+  /*                                                                       */
+  /*    size        :: A handle to the source face size at which the glyph */
+  /*                   must be scaled/loaded.                              */
+  /*                                                                       */
+  /*    glyph_index :: The index of the glyph in the font file.            */
+  /*                                                                       */
+  /*    load_flags  :: A flag indicating what to load for this glyph.  The */
+  /*                   FT_LOAD_XXX constants can be used to control the    */
+  /*                   glyph loading process (e.g., whether the outline    */
+  /*                   should be scaled, whether to load bitmaps or not,   */
+  /*                   whether to hint the outline, etc).                  */
+  /*                                                                       */
+  /* <Return>                                                              */
+  /*    FreeType error code.  0 means success.                             */
+  /*                                                                       */
+  FT_LOCAL_DEF( FT_Error )
+  TT_Load_Glyph( TT_Size       size,
+                 TT_GlyphSlot  glyph,
+                 FT_UInt       glyph_index,
+                 FT_Int32      load_flags )
+  {
+    FT_Error      error;
+    TT_LoaderRec  loader;
+
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+#define IS_DEFAULT_INSTANCE  ( !( FT_IS_NAMED_INSTANCE( glyph->face ) ||  \
+                                  FT_IS_VARIATION( glyph->face )      ) )
+#else
+#define IS_DEFAULT_INSTANCE  1
+#endif
+
+
+    FT_TRACE1(( "TT_Load_Glyph: glyph index %d\n", glyph_index ));
+
+#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
+
+    /* try to load embedded bitmap (if any) */
+    if ( size->strike_index != 0xFFFFFFFFUL      &&
+         ( load_flags & FT_LOAD_NO_BITMAP ) == 0 &&
+         IS_DEFAULT_INSTANCE                     )
+    {
+      FT_Fixed  x_scale = size->root.metrics.x_scale;
+      FT_Fixed  y_scale = size->root.metrics.y_scale;
+
+
+      error = load_sbit_image( size, glyph, glyph_index, load_flags );
+      if ( FT_ERR_EQ( error, Missing_Bitmap ) )
+      {
+        /* the bitmap strike is incomplete and misses the requested glyph; */
+        /* if we have a bitmap-only font, return an empty glyph            */
+        if ( !FT_IS_SCALABLE( glyph->face ) )
+        {
+          TT_Face  face = (TT_Face)glyph->face;
+
+          FT_Short  left_bearing = 0;
+          FT_Short  top_bearing  = 0;
+
+          FT_UShort  advance_width  = 0;
+          FT_UShort  advance_height = 0;
+
+
+          /* to return an empty glyph, however, we need metrics data   */
+          /* from the `hmtx' (or `vmtx') table; the assumption is that */
+          /* empty glyphs are missing intentionally, representing      */
+          /* whitespace - not having at least horizontal metrics is    */
+          /* thus considered an error                                  */
+          if ( !face->horz_metrics_size )
+            return error;
+
+          /* we now construct an empty bitmap glyph */
+          TT_Get_HMetrics( face, glyph_index,
+                           &left_bearing,
+                           &advance_width );
+          TT_Get_VMetrics( face, glyph_index,
+                           0,
+                           &top_bearing,
+                           &advance_height );
+
+          glyph->outline.n_points   = 0;
+          glyph->outline.n_contours = 0;
+
+          glyph->metrics.width  = 0;
+          glyph->metrics.height = 0;
+
+          glyph->metrics.horiBearingX = FT_MulFix( left_bearing, x_scale );
+          glyph->metrics.horiBearingY = 0;
+          glyph->metrics.horiAdvance  = FT_MulFix( advance_width, x_scale );
+
+          glyph->metrics.vertBearingX = 0;
+          glyph->metrics.vertBearingY = FT_MulFix( top_bearing, y_scale );
+          glyph->metrics.vertAdvance  = FT_MulFix( advance_height, y_scale );
+
+          glyph->format            = FT_GLYPH_FORMAT_BITMAP;
+          glyph->bitmap.pixel_mode = FT_PIXEL_MODE_MONO;
+
+          glyph->bitmap_left = 0;
+          glyph->bitmap_top  = 0;
+
+          return FT_Err_Ok;
+        }
+      }
+      else if ( error )
+      {
+        /* return error if font is not scalable */
+        if ( !FT_IS_SCALABLE( glyph->face ) )
+          return error;
+      }
+      else
+      {
+        if ( FT_IS_SCALABLE( glyph->face ) )
+        {
+          /* for the bbox we need the header only */
+          (void)tt_loader_init( &loader, size, glyph, load_flags, TRUE );
+          (void)load_truetype_glyph( &loader, glyph_index, 0, TRUE );
+          tt_loader_done( &loader );
+          glyph->linearHoriAdvance = loader.linear;
+          glyph->linearVertAdvance = loader.vadvance;
+
+          /* sanity checks: if `xxxAdvance' in the sbit metric */
+          /* structure isn't set, use `linearXXXAdvance'      */
+          if ( !glyph->metrics.horiAdvance && glyph->linearHoriAdvance )
+            glyph->metrics.horiAdvance = FT_MulFix( glyph->linearHoriAdvance,
+                                                    x_scale );
+          if ( !glyph->metrics.vertAdvance && glyph->linearVertAdvance )
+            glyph->metrics.vertAdvance = FT_MulFix( glyph->linearVertAdvance,
+                                                    y_scale );
+        }
+
+        return FT_Err_Ok;
+      }
+    }
+
+#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
+
+    /* if FT_LOAD_NO_SCALE is not set, `ttmetrics' must be valid */
+    if ( !( load_flags & FT_LOAD_NO_SCALE ) && !size->ttmetrics.valid )
+    {
+      error = FT_THROW( Invalid_Size_Handle );
+      goto Exit;
+    }
+
+    if ( load_flags & FT_LOAD_SBITS_ONLY )
+    {
+      error = FT_THROW( Invalid_Argument );
+      goto Exit;
+    }
+
+    error = tt_loader_init( &loader, size, glyph, load_flags, FALSE );
+    if ( error )
+      goto Exit;
+
+    glyph->format        = FT_GLYPH_FORMAT_OUTLINE;
+    glyph->num_subglyphs = 0;
+    glyph->outline.flags = 0;
+
+    /* main loading loop */
+    error = load_truetype_glyph( &loader, glyph_index, 0, FALSE );
+    if ( !error )
+    {
+      if ( glyph->format == FT_GLYPH_FORMAT_COMPOSITE )
+      {
+        glyph->num_subglyphs = loader.gloader->base.num_subglyphs;
+        glyph->subglyphs     = loader.gloader->base.subglyphs;
+      }
+      else
+      {
+        glyph->outline        = loader.gloader->base.outline;
+        glyph->outline.flags &= ~FT_OUTLINE_SINGLE_PASS;
+
+        /* Translate array so that (0,0) is the glyph's origin.  Note  */
+        /* that this behaviour is independent on the value of bit 1 of */
+        /* the `flags' field in the `head' table -- at least major     */
+        /* applications like Acroread indicate that.                   */
+        if ( loader.pp1.x )
+          FT_Outline_Translate( &glyph->outline, -loader.pp1.x, 0 );
+      }
+
+#ifdef TT_USE_BYTECODE_INTERPRETER
+
+      if ( IS_HINTED( load_flags ) )
+      {
+        if ( loader.exec->GS.scan_control )
+        {
+          /* convert scan conversion mode to FT_OUTLINE_XXX flags */
+          switch ( loader.exec->GS.scan_type )
+          {
+          case 0: /* simple drop-outs including stubs */
+            glyph->outline.flags |= FT_OUTLINE_INCLUDE_STUBS;
+            break;
+          case 1: /* simple drop-outs excluding stubs */
+            /* nothing; it's the default rendering mode */
+            break;
+          case 4: /* smart drop-outs including stubs */
+            glyph->outline.flags |= FT_OUTLINE_SMART_DROPOUTS |
+                                    FT_OUTLINE_INCLUDE_STUBS;
+            break;
+          case 5: /* smart drop-outs excluding stubs  */
+            glyph->outline.flags |= FT_OUTLINE_SMART_DROPOUTS;
+            break;
+
+          default: /* no drop-out control */
+            glyph->outline.flags |= FT_OUTLINE_IGNORE_DROPOUTS;
+            break;
+          }
+        }
+        else
+          glyph->outline.flags |= FT_OUTLINE_IGNORE_DROPOUTS;
+      }
+
+#endif /* TT_USE_BYTECODE_INTERPRETER */
+
+      error = compute_glyph_metrics( &loader, glyph_index );
+    }
+
+    tt_loader_done( &loader );
+
+    /* Set the `high precision' bit flag.                           */
+    /* This is _critical_ to get correct output for monochrome      */
+    /* TrueType glyphs at all sizes using the bytecode interpreter. */
+    /*                                                              */
+    if ( !( load_flags & FT_LOAD_NO_SCALE ) &&
+         size->metrics->y_ppem < 24         )
+      glyph->outline.flags |= FT_OUTLINE_HIGH_PRECISION;
+
+  Exit:
+#ifdef FT_DEBUG_LEVEL_TRACE
+    if ( error )
+      FT_TRACE1(( "  failed (error code 0x%x)\n",
+                  error ));
+#endif
+
+    return error;
+  }
+
+
+/* END */