ttobjs.c

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  /* <Function>                                                            */
  /*    tt_face_done                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalize a given face object.                                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face :: A pointer to the face object to destroy.                   */
  /*                                                                       */
  FT_LOCAL_DEF( void )
  tt_face_done( FT_Face  ttface )           /* TT_Face */
  {
    TT_Face       face   = (TT_Face)ttface;
    FT_Memory     memory = face->root.memory;
    FT_Stream     stream = face->root.stream;

    SFNT_Service  sfnt   = (SFNT_Service)face->sfnt;


    /* for `extended TrueType formats' (i.e. compressed versions) */
    if ( face->extra.finalizer )
      face->extra.finalizer( face->extra.data );

    if ( sfnt )
      sfnt->done_face( face );

    /* freeing the locations table */
    tt_face_done_loca( face );

    tt_face_free_hdmx( face );

    /* freeing the CVT */
    FT_FREE( face->cvt );
    face->cvt_size = 0;

    /* freeing the programs */
    FT_FRAME_RELEASE( face->font_program );
    FT_FRAME_RELEASE( face->cvt_program );
    face->font_program_size = 0;
    face->cvt_program_size  = 0;

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
    tt_done_blend( memory, face->blend );
    face->blend = NULL;
#endif
  }


  /*************************************************************************/
  /*                                                                       */
  /*                           SIZE  FUNCTIONS                             */
  /*                                                                       */
  /*************************************************************************/

#ifdef TT_USE_BYTECODE_INTERPRETER

  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_size_run_fpgm                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Run the font program.                                              */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the size object.                               */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_size_run_fpgm( TT_Size  size )
  {
    TT_Face         face = (TT_Face)size->root.face;
    TT_ExecContext  exec;
    FT_Error        error;


    /* debugging instances have their own context */
    if ( size->debug )
      exec = size->context;
    else
      exec = ( (TT_Driver)FT_FACE_DRIVER( face ) )->context;

    if ( !exec )
      return TT_Err_Could_Not_Find_Context;

    TT_Load_Context( exec, face, size );

    exec->callTop   = 0;
    exec->top       = 0;

    exec->period    = 64;
    exec->phase     = 0;
    exec->threshold = 0;

    exec->instruction_trap = FALSE;
    exec->F_dot_P = 0x10000L;

    {
      FT_Size_Metrics*  metrics    = &exec->metrics;
      TT_Size_Metrics*  tt_metrics = &exec->tt_metrics;


      metrics->x_ppem   = 0;
      metrics->y_ppem   = 0;
      metrics->x_scale  = 0;
      metrics->y_scale  = 0;

      tt_metrics->ppem  = 0;
      tt_metrics->scale = 0;
      tt_metrics->ratio = 0x10000L;
    }

    /* allow font program execution */
    TT_Set_CodeRange( exec,
                      tt_coderange_font,
                      face->font_program,
                      face->font_program_size );

    /* disable CVT and glyph programs coderange */
    TT_Clear_CodeRange( exec, tt_coderange_cvt );
    TT_Clear_CodeRange( exec, tt_coderange_glyph );

    if ( face->font_program_size > 0 )
    {
      error = TT_Goto_CodeRange( exec, tt_coderange_font, 0 );

      if ( !error )
        error = face->interpreter( exec );
    }
    else
      error = TT_Err_Ok;

    if ( !error )
      TT_Save_Context( exec, size );

    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_size_run_prep                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Run the control value program.                                     */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the size object.                               */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_size_run_prep( TT_Size  size )
  {
    TT_Face         face = (TT_Face)size->root.face;
    TT_ExecContext  exec;
    FT_Error        error;


    /* debugging instances have their own context */
    if ( size->debug )
      exec = size->context;
    else
      exec = ( (TT_Driver)FT_FACE_DRIVER( face ) )->context;

    if ( !exec )
      return TT_Err_Could_Not_Find_Context;

    TT_Load_Context( exec, face, size );

    exec->callTop = 0;
    exec->top     = 0;

    exec->instruction_trap = FALSE;

    TT_Set_CodeRange( exec,
                      tt_coderange_cvt,
                      face->cvt_program,
                      face->cvt_program_size );

    TT_Clear_CodeRange( exec, tt_coderange_glyph );

    if ( face->cvt_program_size > 0 )
    {
      error = TT_Goto_CodeRange( exec, tt_coderange_cvt, 0 );

      if ( !error && !size->debug )
        error = face->interpreter( exec );
    }
    else
      error = TT_Err_Ok;

    /* save as default graphics state */
    size->GS = exec->GS;

    TT_Save_Context( exec, size );

    return error;
  }

#endif /* TT_USE_BYTECODE_INTERPRETER */


#ifdef TT_USE_BYTECODE_INTERPRETER

  static void
  tt_size_done_bytecode( FT_Size  ftsize )
  {
    TT_Size    size   = (TT_Size)ftsize;
    TT_Face    face   = (TT_Face)ftsize->face;
    FT_Memory  memory = face->root.memory;


    if ( size->debug )
    {
      /* the debug context must be deleted by the debugger itself */
      size->context = NULL;
      size->debug   = FALSE;
    }

    FT_FREE( size->cvt );
    size->cvt_size = 0;

    /* free storage area */
    FT_FREE( size->storage );
    size->storage_size = 0;

    /* twilight zone */
    tt_glyphzone_done( &size->twilight );

    FT_FREE( size->function_defs );
    FT_FREE( size->instruction_defs );

    size->num_function_defs    = 0;
    size->max_function_defs    = 0;
    size->num_instruction_defs = 0;
    size->max_instruction_defs = 0;

    size->max_func = 0;
    size->max_ins  = 0;

    size->bytecode_ready = 0;
    size->cvt_ready      = 0;
  }


  /* Initialize bytecode-related fields in the size object.       */
  /* We do this only if bytecode interpretation is really needed. */
  static FT_Error
  tt_size_init_bytecode( FT_Size  ftsize )
  {
    FT_Error   error;
    TT_Size    size = (TT_Size)ftsize;
    TT_Face    face = (TT_Face)ftsize->face;
    FT_Memory  memory = face->root.memory;
    FT_Int     i;

    FT_UShort       n_twilight;
    TT_MaxProfile*  maxp = &face->max_profile;


    size->bytecode_ready = 1;
    size->cvt_ready      = 0;

    size->max_function_defs    = maxp->maxFunctionDefs;
    size->max_instruction_defs = maxp->maxInstructionDefs;

    size->num_function_defs    = 0;
    size->num_instruction_defs = 0;

    size->max_func = 0;
    size->max_ins  = 0;

    size->cvt_size     = face->cvt_size;
    size->storage_size = maxp->maxStorage;

    /* Set default metrics */
    {
      FT_Size_Metrics*  metrics  = &size->metrics;
      TT_Size_Metrics*  metrics2 = &size->ttmetrics;

      metrics->x_ppem = 0;
      metrics->y_ppem = 0;

      metrics2->rotated   = FALSE;
      metrics2->stretched = FALSE;

      /* set default compensation (all 0) */
      for ( i = 0; i < 4; i++ )
        metrics2->compensations[i] = 0;
    }

    /* allocate function defs, instruction defs, cvt, and storage area */
    if ( FT_NEW_ARRAY( size->function_defs,    size->max_function_defs    ) ||
         FT_NEW_ARRAY( size->instruction_defs, size->max_instruction_defs ) ||
         FT_NEW_ARRAY( size->cvt,              size->cvt_size             ) ||
         FT_NEW_ARRAY( size->storage,          size->storage_size         ) )
      goto Exit;

    /* reserve twilight zone */
    n_twilight = maxp->maxTwilightPoints;

    /* there are 4 phantom points (do we need this?) */
    n_twilight += 4;

    error = tt_glyphzone_new( memory, n_twilight, 0, &size->twilight );
    if ( error )
      goto Exit;

    size->twilight.n_points = n_twilight;