ttobjs.c

来自「一个类似windows」· C语言 代码 · 共 916 行 · 第 1/3 页

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


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


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_size_init                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a new TrueType size object.                            */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    size :: A handle to the size object.                               */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  tt_size_init( FT_Size  ttsize )           /* TT_Size */
  {
    TT_Size   size  = (TT_Size)ttsize;
    FT_Error  error = TT_Err_Ok;


#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER

    TT_Face    face   = (TT_Face)size->root.face;
    FT_Memory  memory = face->root.memory;
    FT_Int     i;

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


    size->ttmetrics.valid = FALSE;

    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->root.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 Fail_Memory;

    /* reserve twilight zone */
    n_twilight = maxp->maxTwilightPoints;
    error = tt_glyphzone_new( memory, n_twilight, 0, &size->twilight );
    if ( error )
      goto Fail_Memory;

    size->twilight.n_points = n_twilight;

    /* set `face->interpreter' according to the debug hook present */
    {
      FT_Library  library = face->root.driver->root.library;


      face->interpreter = (TT_Interpreter)
                            library->debug_hooks[FT_DEBUG_HOOK_TRUETYPE];
      if ( !face->interpreter )
        face->interpreter = (TT_Interpreter)TT_RunIns;
    }

    /* Fine, now execute the font program! */
    exec = size->context;
    /* size objects used during debugging have their own context */
    if ( !size->debug )
      exec = TT_New_Context( face );

    if ( !exec )
    {
      error = TT_Err_Could_Not_Find_Context;
      goto Fail_Memory;
    }

    size->GS = tt_default_graphics_state;
    TT_Load_Context( exec, face, size );

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

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

    {
      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;
    }

    exec->instruction_trap = FALSE;

    exec->cvtSize = size->cvt_size;
    exec->cvt     = size->cvt;

    exec->F_dot_P = 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 );

      if ( error )
        goto Fail_Exec;
    }
    else
      error = TT_Err_Ok;

    TT_Save_Context( exec, size );

    if ( !size->debug )
      TT_Done_Context( exec );

#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

    size->ttmetrics.valid = FALSE;
    return error;

#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER

  Fail_Exec:
    if ( !size->debug )
      TT_Done_Context( exec );

  Fail_Memory:

    tt_size_done( ttsize );
    return error;

#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    tt_size_done                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType size object finalizer.                                */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the target size object.                        */
  /*                                                                       */
  FT_LOCAL_DEF( void )
  tt_size_done( FT_Size  ttsize )           /* TT_Size */
  {
    TT_Size    size = (TT_Size)ttsize;

#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER

    FT_Memory  memory = size->root.face->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;

#endif

    size->ttmetrics.valid = FALSE;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Reset_Outline_Size                                                 */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Resets a TrueType outline size when resolutions and character      */
  /*    dimensions have been changed.                                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the target size object.                        */
  /*                                                                       */
  static FT_Error
  Reset_Outline_Size( TT_Size  size )
  {
    TT_Face           face;
    FT_Error          error = TT_Err_Ok;

    FT_Size_Metrics*  metrics;


    if ( size->ttmetrics.valid )
      return TT_Err_Ok;

    face = (TT_Face)size->root.face;

    metrics = &size->metrics;

    if ( metrics->x_ppem < 1 || metrics->y_ppem < 1 )
      return TT_Err_Invalid_PPem;

    /* compute new transformation */
    if ( metrics->x_ppem >= metrics->y_ppem )
    {
      size->ttmetrics.scale   = metrics->x_scale;
      size->ttmetrics.ppem    = metrics->x_ppem;
      size->ttmetrics.x_ratio = 0x10000L;
      size->ttmetrics.y_ratio = FT_MulDiv( metrics->y_ppem,
                                           0x10000L,
                                           metrics->x_ppem );
    }
    else
    {
      size->ttmetrics.scale   = metrics->y_scale;
      size->ttmetrics.ppem    = metrics->y_ppem;
      size->ttmetrics.x_ratio = FT_MulDiv( metrics->x_ppem,
                                           0x10000L,
                                           metrics->y_ppem );
      size->ttmetrics.y_ratio = 0x10000L;
    }

    /* Compute root ascender, descender, text height, and max_advance */
    metrics->ascender =
      FT_PIX_ROUND( FT_MulFix( face->root.ascender, metrics->y_scale ) );