t1decode.c

qt-embedded-2.3.8.tar.gz源码

/***************************************************************************/
/*                                                                         */
/*  t1decode.c                                                             */
/*                                                                         */
/*    PostScript Type 1 decoding routines (body).                          */
/*                                                                         */
/*  Copyright 2000 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 <freetype/internal/ftdebug.h> /* for FT_ERROR() */
#include <freetype/internal/t1errors.h>
#include <freetype/ftoutln.h>
#include <freetype/internal/ftdebug.h>


#ifdef FT_FLAT_COMPILE

#include "t1decode.h"
#include "psobjs.h"

#else

#include <psaux/t1decode.h>
#include <psaux/psobjs.h>

#endif


  /*************************************************************************/
  /*                                                                       */
  /* 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_t1decode


  typedef enum  T1_Operator_
  {
    op_none = 0,
    op_endchar,
    op_hsbw,
    op_seac,
    op_sbw,
    op_closepath,
    op_hlineto,
    op_hmoveto,
    op_hvcurveto,
    op_rlineto,
    op_rmoveto,
    op_rrcurveto,
    op_vhcurveto,
    op_vlineto,
    op_vmoveto,
    op_dotsection,
    op_hstem,
    op_hstem3,
    op_vstem,
    op_vstem3,
    op_div,
    op_callothersubr,
    op_callsubr,
    op_pop,
    op_return,
    op_setcurrentpoint,

    op_max    /* never remove this one */

  } T1_Operator;

  static
  const FT_Int  t1_args_count[op_max] =
  {
    0, /* none */
    0, /* endchar */
    2, /* hsbw */
    5, /* seac */
    4, /* sbw */
    0, /* closepath */
    1, /* hlineto */
    1, /* hmoveto */
    4, /* hvcurveto */
    2, /* rlineto */
    2, /* rmoveto */
    6, /* rrcurveto */
    4, /* vhcurveto */
    1, /* vlineto */
    1, /* vmoveto */
    0, /* dotsection */
    2, /* hstem */
    6, /* hstem3 */
    2, /* vstem */
    6, /* vstem3 */
    2, /* div */
   -1, /* callothersubr */
    1, /* callsubr */
    0, /* pop */
    0, /* return */
    2  /* setcurrentpoint */
  };


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    t1_lookup_glyph_by_stdcharcode                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Looks up a given glyph by its StandardEncoding charcode.  Used to  */
  /*    implement the SEAC Type 1 operator.                                */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face     :: The current face object.                               */
  /*                                                                       */
  /*    charcode :: The character code to look for.                        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    A glyph index in the font face.  Returns -1 if the corresponding   */
  /*    glyph wasn't found.                                                */
  /*                                                                       */
  static
  FT_Int  t1_lookup_glyph_by_stdcharcode( T1_Decoder*  decoder,
                                          FT_Int       charcode )
  {
    FT_UInt             n;
    const FT_String*    glyph_name;
    PSNames_Interface*  psnames = decoder->psnames;


    /* check range of standard char code */
    if ( charcode < 0 || charcode > 255 )
      return -1;

    glyph_name = psnames->adobe_std_strings(
                   psnames->adobe_std_encoding[charcode]);

    for ( n = 0; n < decoder->num_glyphs; n++ )
    {
      FT_String*  name = (FT_String*)decoder->glyph_names[n];


      if ( name && strcmp( name,glyph_name ) == 0 )
        return n;
    }

    return -1;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    t1operator_seac                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Implements the `seac' Type 1 operator for a Type 1 decoder.        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    decoder :: The current CID decoder.                                */
  /*                                                                       */
  /*    asb     :: The accent's side bearing.                              */
  /*                                                                       */
  /*    adx     :: The horizontal offset of the accent.                    */
  /*                                                                       */
  /*    ady     :: The vertical offset of the accent.                      */
  /*                                                                       */
  /*    bchar   :: The base character's StandardEncoding charcode.         */
  /*                                                                       */
  /*    achar   :: The accent character's StandardEncoding charcode.       */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static
  FT_Error  t1operator_seac( T1_Decoder*  decoder,
                             FT_Pos       asb,
                             FT_Pos       adx,
                             FT_Pos       ady,
                             FT_Int       bchar,
                             FT_Int       achar )
  {
    FT_Error     error;
    FT_Int       bchar_index, achar_index, n_base_points;
    FT_Outline*  base = decoder->builder.base;
    FT_Vector    left_bearing, advance;


    /* seac weirdness */
    adx += decoder->builder.left_bearing.x;

    /* `glyph_names' is set to 0 for CID fonts which do not */
    /* include an encoding.  How can we deal with these?    */
    if ( decoder->glyph_names == 0 )
    {
      FT_ERROR(( "t1operator_seac:" ));
      FT_ERROR(( " glyph names table not available in this font!\n" ));
      return T1_Err_Syntax_Error;
    }

    bchar_index = t1_lookup_glyph_by_stdcharcode( decoder, bchar );
    achar_index = t1_lookup_glyph_by_stdcharcode( decoder, achar );

    if ( bchar_index < 0 || achar_index < 0 )
    {
      FT_ERROR(( "t1operator_seac:" ));
      FT_ERROR(( " invalid seac character code arguments\n" ));
      return T1_Err_Syntax_Error;
    }

    /* if we are trying to load a composite glyph, do not load the */
    /* accent character and return the array of subglyphs.         */
    if ( decoder->builder.no_recurse )
    {
      FT_GlyphSlot     glyph  = (FT_GlyphSlot)decoder->builder.glyph;
      FT_GlyphLoader*  loader = glyph->internal->loader;
      FT_SubGlyph*     subg;


      /* reallocate subglyph array if necessary */
      error = FT_GlyphLoader_Check_Subglyphs( loader, 2 );
      if ( error )
        goto Exit;

      subg = loader->current.subglyphs;

      /* subglyph 0 = base character */
      subg->index = bchar_index;
      subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES |
                    FT_SUBGLYPH_FLAG_USE_MY_METRICS;
      subg->arg1  = 0;
      subg->arg2  = 0;
      subg++;

      /* subglyph 1 = accent character */
      subg->index = achar_index;
      subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES;
      subg->arg1  = adx - asb;
      subg->arg2  = ady;

      /* set up remaining glyph fields */
      glyph->num_subglyphs = 2;
      glyph->subglyphs     = loader->base.subglyphs;
      glyph->format        = ft_glyph_format_composite;

      loader->current.num_subglyphs = 2;
    }

    /* First load `bchar' in builder */
    /* now load the unscaled outline */

    FT_GlyphLoader_Prepare( decoder->builder.loader );  /* prepare loader */

    error = T1_Decoder_Parse_Glyph( decoder, bchar_index );
    if ( error )
      goto Exit;

    n_base_points = base->n_points;

    /* save the left bearing and width of the base character */
    /* as they will be erased by the next load.              */

    left_bearing = decoder->builder.left_bearing;
    advance      = decoder->builder.advance;

    decoder->builder.left_bearing.x = 0;
    decoder->builder.left_bearing.y = 0;

    /* Now load `achar' on top of */
    /* the base outline           */
    error = T1_Decoder_Parse_Glyph( decoder, achar_index );
    if ( error )
      goto Exit;

    /* restore the left side bearing and   */
    /* advance width of the base character */

    decoder->builder.left_bearing = left_bearing;
    decoder->builder.advance      = advance;

    /* Finally, move the accent */
    if ( decoder->builder.load_points )
    {
      FT_Outline  dummy;


      dummy.n_points = base->n_points - n_base_points;
      dummy.points   = base->points   + n_base_points;

      FT_Outline_Translate( &dummy, adx - asb, ady );
    }

  Exit:
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    T1_Decoder_Parse_Charstrings                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Parses a given Type 1 charstrings program.                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    decoder         :: The current Type 1 decoder.                     */
  /*                                                                       */
  /*    charstring_base :: The base address of the charstring stream.      */
  /*                                                                       */
  /*    charstring_len  :: The length in bytes of the charstring stream.   */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF
  FT_Error  T1_Decoder_Parse_Charstrings( T1_Decoder*  decoder,
                                          FT_Byte*     charstring_base,
                                          FT_UInt      charstring_len )
  {
    FT_Error          error;
    T1_Decoder_Zone*  zone;
    FT_Byte*          ip;
    FT_Byte*          limit;
    T1_Builder*       builder = &decoder->builder;
    FT_Outline*       outline;
    FT_Pos            x, y;


    /* we don't want to touch the source code -- use macro trick */
#define start_point    T1_Builder_Start_Point
#define check_points   T1_Builder_Check_Points
#define add_point      T1_Builder_Add_Point
#define add_point1     T1_Builder_Add_Point1
#define add_contour    T1_Builder_Add_Contour
#define close_contour  T1_Builder_Close_Contour

    /* First of all, initialize the decoder */
    decoder->top  = decoder->stack;
    decoder->zone = decoder->zones;
    zone          = decoder->zones;

    builder->path_begun  = 0;

    zone->base           = charstring_base;
    limit = zone->limit  = charstring_base + charstring_len;
    ip    = zone->cursor = zone->base;

    error   = FT_Err_Ok;
    outline = builder->current;