freetype2/src/type42/t42drivr.c

/****************************************************************************
 *
 * t42drivr.c
 *
 *   High-level Type 42 driver interface (body).
 *
 * Copyright (C) 2002-2021 by
 * Roberto Alameda.
 *
 * 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.
 *
 */


  /**************************************************************************
   *
   * This driver implements Type42 fonts as described in the
   * Technical Note #5012 from Adobe, with these limitations:
   *
   * 1) CID Fonts are not currently supported.
   * 2) Incremental fonts making use of the GlyphDirectory keyword
   *    will be loaded, but the rendering will be using the TrueType
   *    tables.
   * 3) As for Type1 fonts, CDevProc is not supported.
   * 4) The Metrics dictionary is not supported.
   * 5) AFM metrics are not supported.
   *
   * In other words, this driver supports Type42 fonts derived from
   * TrueType fonts in a non-CID manner, as done by usual conversion
   * programs.
   *
   */


#include "t42drivr.h"
#include "t42objs.h"
#include "t42error.h"
#include <freetype/internal/ftdebug.h>

#include <freetype/internal/services/svfntfmt.h>
#include <freetype/internal/services/svgldict.h>
#include <freetype/internal/services/svpostnm.h>
#include <freetype/internal/services/svpsinfo.h>

#undef  FT_COMPONENT
#define FT_COMPONENT  t42


  /*
   *
   * GLYPH DICT SERVICE
   *
   */

  static FT_Error
  t42_get_glyph_name( T42_Face    face,
                      FT_UInt     glyph_index,
                      FT_Pointer  buffer,
                      FT_UInt     buffer_max )
  {
    FT_STRCPYN( buffer, face->type1.glyph_names[glyph_index], buffer_max );

    return FT_Err_Ok;
  }


  static FT_UInt
  t42_get_name_index( T42_Face          face,
                      const FT_String*  glyph_name )
  {
    FT_Int  i;


    for ( i = 0; i < face->type1.num_glyphs; i++ )
    {
      FT_String*  gname = face->type1.glyph_names[i];


      if ( glyph_name[0] == gname[0] && !ft_strcmp( glyph_name, gname ) )
        return (FT_UInt)ft_strtol( (const char *)face->type1.charstrings[i],
                                   NULL, 10 );
    }

    return 0;
  }


  static const FT_Service_GlyphDictRec  t42_service_glyph_dict =
  {
    (FT_GlyphDict_GetNameFunc)  t42_get_glyph_name,    /* get_name   */
    (FT_GlyphDict_NameIndexFunc)t42_get_name_index     /* name_index */
  };


  /*
   *
   * POSTSCRIPT NAME SERVICE
   *
   */

  static const char*
  t42_get_ps_font_name( T42_Face  face )
  {
    return (const char*)face->type1.font_name;
  }


  static const FT_Service_PsFontNameRec  t42_service_ps_font_name =
  {
    (FT_PsName_GetFunc)t42_get_ps_font_name   /* get_ps_font_name */
  };


  /*
   *
   * POSTSCRIPT INFO SERVICE
   *
   */

  static FT_Error
  t42_ps_get_font_info( FT_Face          face,
                        PS_FontInfoRec*  afont_info )
  {
    *afont_info = ((T42_Face)face)->type1.font_info;

    return FT_Err_Ok;
  }


  static FT_Error
  t42_ps_get_font_extra( FT_Face           face,
                         PS_FontExtraRec*  afont_extra )
  {
    *afont_extra = ((T42_Face)face)->type1.font_extra;

    return FT_Err_Ok;
  }


  static FT_Int
  t42_ps_has_glyph_names( FT_Face  face )
  {
    FT_UNUSED( face );

    return 1;
  }


  static FT_Error
  t42_ps_get_font_private( FT_Face         face,
                           PS_PrivateRec*  afont_private )
  {
    *afont_private = ((T42_Face)face)->type1.private_dict;

    return FT_Err_Ok;
  }


  static const FT_Service_PsInfoRec  t42_service_ps_info =
  {
    (PS_GetFontInfoFunc)   t42_ps_get_font_info,    /* ps_get_font_info    */
    (PS_GetFontExtraFunc)  t42_ps_get_font_extra,   /* ps_get_font_extra   */
    (PS_HasGlyphNamesFunc) t42_ps_has_glyph_names,  /* ps_has_glyph_names  */
    (PS_GetFontPrivateFunc)t42_ps_get_font_private, /* ps_get_font_private */
    /* not implemented */
    (PS_GetFontValueFunc)  NULL                     /* ps_get_font_value   */
  };


  /*
   *
   * SERVICE LIST
   *
   */

  static const FT_ServiceDescRec  t42_services[] =
  {
    { FT_SERVICE_ID_GLYPH_DICT,           &t42_service_glyph_dict },
    { FT_SERVICE_ID_POSTSCRIPT_FONT_NAME, &t42_service_ps_font_name },
    { FT_SERVICE_ID_POSTSCRIPT_INFO,      &t42_service_ps_info },
    { FT_SERVICE_ID_FONT_FORMAT,          FT_FONT_FORMAT_TYPE_42 },
    { NULL, NULL }
  };


  FT_CALLBACK_DEF( FT_Module_Interface )
  T42_Get_Interface( FT_Module         module,
                     const FT_String*  t42_interface )
  {
    FT_UNUSED( module );

    return ft_service_list_lookup( t42_services, t42_interface );
  }


  const FT_Driver_ClassRec  t42_driver_class =
  {
    {
      FT_MODULE_FONT_DRIVER       |
      FT_MODULE_DRIVER_SCALABLE   |
#ifdef TT_USE_BYTECODE_INTERPRETER
      FT_MODULE_DRIVER_HAS_HINTER,
#else
      0,
#endif

      sizeof ( T42_DriverRec ),

      "type42",
      0x10000L,
      0x20000L,

      NULL,    /* module-specific interface */

      T42_Driver_Init,          /* FT_Module_Constructor  module_init   */
      T42_Driver_Done,          /* FT_Module_Destructor   module_done   */
      T42_Get_Interface,        /* FT_Module_Requester    get_interface */
    },

    sizeof ( T42_FaceRec ),
    sizeof ( T42_SizeRec ),
    sizeof ( T42_GlyphSlotRec ),

    T42_Face_Init,              /* FT_Face_InitFunc  init_face */
    T42_Face_Done,              /* FT_Face_DoneFunc  done_face */
    T42_Size_Init,              /* FT_Size_InitFunc  init_size */
    T42_Size_Done,              /* FT_Size_DoneFunc  done_size */
    T42_GlyphSlot_Init,         /* FT_Slot_InitFunc  init_slot */
    T42_GlyphSlot_Done,         /* FT_Slot_DoneFunc  done_slot */

    T42_GlyphSlot_Load,         /* FT_Slot_LoadFunc  load_glyph */

    NULL,                       /* FT_Face_GetKerningFunc   get_kerning  */
    NULL,                       /* FT_Face_AttachFunc       attach_file  */
    NULL,                       /* FT_Face_GetAdvancesFunc  get_advances */

    T42_Size_Request,           /* FT_Size_RequestFunc  request_size */
    T42_Size_Select             /* FT_Size_SelectFunc   select_size  */
  };


/* END */