ttobjs.c

Qt/Embedded是一个多平台的C++图形用户界面应用程序框架

    /* allocate function defs, instruction defs, cvt and storage area */
    if ( ALLOC_ARRAY( size->function_defs,
                      size->max_function_defs,
                      TT_DefRecord )                ||

         ALLOC_ARRAY( size->instruction_defs,
                      size->max_instruction_defs,
                      TT_DefRecord )                ||

         ALLOC_ARRAY( size->cvt,
                      size->cvt_size, TT_Long )     ||

         ALLOC_ARRAY( size->storage,
                      size->storage_size, TT_Long ) )

      goto Fail_Memory;

    /* reserve twilight zone */
    n_twilight = maxp->maxTwilightPoints;
    error = FT_New_GlyphZone( 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->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;
    if (!size->debug)
      exec = TT_New_Context( face );
    /* size objects used during debugging have their own context */

    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  = 0x10000;
    }

    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:
#endif

    TT_Done_Size( size );
    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Done_Size                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType size object finalizer.                                */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the target size object.                        */
  /*                                                                       */
  LOCAL_FUNC
  void  TT_Done_Size( TT_Size  size )
  {
#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;
    }

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

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

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

    FREE( size->function_defs );
    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>                                                            */
  /*    TT_Reset_Size                                                      */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Resets a TrueType size when resolutions and character dimensions   */
  /*    have been changed.                                                 */
  /*                                                                       */
  /* <Input>                                                               */
  /*    size :: A handle to the target size object.                        */
  /*                                                                       */
  LOCAL_DEF
  TT_Error  TT_Reset_Size( TT_Size  size )
  {
    TT_Face   face;
    TT_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->root.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 = 0x10000;
      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 = 0x10000;
    }

    /* Compute root ascender, descender, test height, and max_advance */
    metrics->ascender = ( FT_MulFix( face->root.ascender,
                                     metrics->y_scale ) + 32 ) & -64;

    metrics->descender = ( FT_MulFix( face->root.descender,
                                      metrics->y_scale ) + 32 ) & -64;

    metrics->height = ( FT_MulFix( face->root.height,
                                   metrics->y_scale ) + 32 ) & -64;

    metrics->max_advance = ( FT_MulFix( face->root.max_advance_width,
                                        metrics->x_scale ) + 32 ) & -64;

#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
    {
      TT_ExecContext    exec;
      TT_UInt  i, j;
      
      /* Scale the cvt values to the new ppem.          */
      /* We use by default the y ppem to scale the CVT. */
  
      for ( i = 0; i < size->cvt_size; i++ )
        size->cvt[i] = FT_MulFix( face->cvt[i], size->ttmetrics.scale );
  
      /* All twilight points are originally zero */
      for ( j = 0; j < size->twilight.n_points; j++ )
      {
        size->twilight.org[j].x = 0;
        size->twilight.org[j].y = 0;
        size->twilight.cur[j].x = 0;
        size->twilight.cur[j].y = 0;
      }
  
      /* clear storage area */
      for ( i = 0; i < size->storage_size; i++ )
        size->storage[i] = 0;
  
      size->GS = tt_default_graphics_state;
  
      /* get execution context and run prep program */
      if ( size->debug )
        exec = size->context;
      else
        exec = TT_New_Context( face );
      /* debugging instances have their own context */
  
      if ( !exec )
        return TT_Err_Could_Not_Find_Context;
  
      TT_Load_Context( exec, face, size );
  
      TT_Set_CodeRange( exec,
                        tt_coderange_cvt,
                        face->cvt_program,
                        face->cvt_program_size );
  
      TT_Clear_CodeRange( exec, tt_coderange_glyph );
  
      exec->instruction_trap = FALSE;
  
      exec->top     = 0;
      exec->callTop = 0;
  
      if ( face->cvt_program_size > 0 )
      {
        error = TT_Goto_CodeRange( exec, tt_coderange_cvt, 0 );
        if ( error )
          goto Fin;
  
        if ( !size->debug )
          error = face->interpreter( exec );
      }
      else
        error = TT_Err_Ok;
  
      size->GS = exec->GS;
      /* save default graphics state */
  
    Fin:
      TT_Save_Context( exec, size );
  
      if ( !size->debug )
        TT_Done_Context( exec );
      /* debugging instances keep their context */
    }
#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

    if ( !error )
      size->ttmetrics.valid = TRUE;

    return error;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Init_GlyphSlot                                                  */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType glyph slot initializer.                               */
  /*                                                                       */
  /* <Input>                                                               */
  /*    slot :: The glyph record to build.                                 */
  /*                                                                       */
  /* <Output>                                                              */
  /*    TrueType error code.  0 means success.                             */
  /*                                                                       */
  LOCAL_FUNC
  TT_Error  TT_Init_GlyphSlot( TT_GlyphSlot  slot )
  {
    /* allocate the outline space */
    FT_Face     face    = slot->face;
    FT_Library  library = face->driver->library;


    FT_TRACE4(( "TT.Init_GlyphSlot: Creating outline maxp = %d, maxc = %d\n",
                face->max_points, face->max_contours ));

    return FT_Outline_New( library,
                           face->max_points + 2,
                           face->max_contours,
                           &slot->outline );
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Done_GlyphSlot                                                  */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType glyph slot finalizer.                                 */
  /*                                                                       */
  /* <Input>                                                               */
  /*    slot :: A handle to the glyph slot object.                         */
  /*                                                                       */
  LOCAL_FUNC
  void  TT_Done_GlyphSlot( TT_GlyphSlot  slot )
  {
    FT_Library  library = slot->face->driver->library;


    FT_Outline_Done( library, &slot->outline );
    return;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Init_Driver                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a given TrueType driver object.                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    driver :: A handle to the target driver object.                    */
  /*                                                                       */
  /* <Return>                                                              */
  /*    TrueType error code.  0 means success.                             */
  /*                                                                       */
  LOCAL_FUNC
  TT_Error  TT_Init_Driver( TT_Driver  driver )
  {
    FT_Memory  memory = driver->root.memory;
    FT_Error   error;
    
    error = FT_New_GlyphZone( memory, 0, 0, &driver->zone );
    if (error) return error;
    
    /* init extension registry if needed */
#ifdef TT_CONFIG_OPTION_EXTEND_ENGINE
    return TT_Init_Extensions( driver );
#else
    return TT_Err_Ok;
#endif
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Done_Driver                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalizes a given TrueType driver.                                 */
  /*                                                                       */
  /* <Input>                                                               */
  /*    driver :: A handle to the target TrueType driver.                  */
  /*                                                                       */
  LOCAL_FUNC
  void  TT_Done_Driver( TT_Driver  driver )
  {
    /* destroy extensions registry if needed */
#ifdef TT_CONFIG_OPTION_EXTEND_ENGINE
    TT_Done_Extensions( driver );
#endif

    /* remove the loading glyph zone */
    FT_Done_GlyphZone( &driver->zone );

#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
    /* destroy the execution context */
    if ( driver->context )
    {
      TT_Destroy_Context( driver->context, driver->root.memory );
      driver->context = NULL;
    }
#endif
  }


/* END */