ftobjs.c

a very goog book

  FT_BASE_DEF( FT_Error )
  FT_Render_Glyph_Internal( FT_Library    library,
                            FT_GlyphSlot  slot,
                            FT_UInt       render_mode )
  {
    FT_Error     error = FT_Err_Ok;
    FT_Renderer  renderer;


    /* if it is already a bitmap, no need to do anything */
    switch ( slot->format )
    {
    case ft_glyph_format_bitmap:   /* already a bitmap, don't do anything */
      break;

    default:
      {
        FT_ListNode  node   = 0;
        FT_Bool      update = 0;


        /* small shortcut for the very common case */
        if ( slot->format == ft_glyph_format_outline )
        {
          renderer = library->cur_renderer;
          node     = library->renderers.head;
        }
        else
          renderer = FT_Lookup_Renderer( library, slot->format, &node );

        error = FT_Err_Unimplemented_Feature;
        while ( renderer )
        {
          error = renderer->render( renderer, slot, render_mode, NULL );
          if ( !error ||
               FT_ERROR_BASE( error ) != FT_Err_Cannot_Render_Glyph )
            break;

          /* FT_Err_Cannot_Render_Glyph is returned if the render mode   */
          /* is unsupported by the current renderer for this glyph image */
          /* format.                                                     */

          /* now, look for another renderer that supports the same */
          /* format.                                               */
          renderer = FT_Lookup_Renderer( library, slot->format, &node );
          update   = 1;
        }

        /* if we changed the current renderer for the glyph image format */
        /* we need to select it as the next current one                  */
        if ( !error && update && renderer )
          FT_Set_Renderer( library, renderer, 0, 0 );
      }
    }

    return error;
  }


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Render_Glyph( FT_GlyphSlot  slot,
                   FT_UInt       render_mode )
  {
    FT_Library  library;


    if ( !slot )
      return FT_Err_Invalid_Argument;

    library = FT_FACE_LIBRARY( slot->face );

    return FT_Render_Glyph_Internal( library, slot, render_mode );
  }


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****                                                                 ****/
  /****                         M O D U L E S                           ****/
  /****                                                                 ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Destroy_Module                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Destroys a given module object.  For drivers, this also destroys   */
  /*    all child faces.                                                   */
  /*                                                                       */
  /* <InOut>                                                               */
  /*     module :: A handle to the target driver object.                   */
  /*                                                                       */
  /* <Note>                                                                */
  /*     The driver _must_ be LOCKED!                                      */
  /*                                                                       */
  static void
  Destroy_Module( FT_Module  module )
  {
    FT_Memory         memory  = module->memory;
    FT_Module_Class*  clazz   = module->clazz;
    FT_Library        library = module->library;


    /* finalize client-data - before anything else */
    if ( module->generic.finalizer )
      module->generic.finalizer( module );

    if ( library && library->auto_hinter == module )
      library->auto_hinter = 0;

    /* if the module is a renderer */
    if ( FT_MODULE_IS_RENDERER( module ) )
      ft_remove_renderer( module );

    /* if the module is a font driver, add some steps */
    if ( FT_MODULE_IS_DRIVER( module ) )
      Destroy_Driver( FT_DRIVER( module ) );

    /* finalize the module object */
    if ( clazz->module_done )
      clazz->module_done( module );

    /* discard it */
    FT_FREE( module );
  }


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Add_Module( FT_Library              library,
                 const FT_Module_Class*  clazz )
  {
    FT_Error   error;
    FT_Memory  memory;
    FT_Module  module;
    FT_UInt    nn;


#define FREETYPE_VER_FIXED  ( ( (FT_Long)FREETYPE_MAJOR << 16 ) | \
                                FREETYPE_MINOR                  )

    if ( !library )
      return FT_Err_Invalid_Library_Handle;

    if ( !clazz )
      return FT_Err_Invalid_Argument;

    /* check freetype version */
    if ( clazz->module_requires > FREETYPE_VER_FIXED )
      return FT_Err_Invalid_Version;

    /* look for a module with the same name in the library's table */
    for ( nn = 0; nn < library->num_modules; nn++ )
    {
      module = library->modules[nn];
      if ( ft_strcmp( module->clazz->module_name, clazz->module_name ) == 0 )
      {
        /* this installed module has the same name, compare their versions */
        if ( clazz->module_version <= module->clazz->module_version )
          return FT_Err_Lower_Module_Version;

        /* remove the module from our list, then exit the loop to replace */
        /* it by our new version..                                        */
        FT_Remove_Module( library, module );
        break;
      }
    }

    memory = library->memory;
    error  = FT_Err_Ok;

    if ( library->num_modules >= FT_MAX_MODULES )
    {
      error = FT_Err_Too_Many_Drivers;
      goto Exit;
    }

    /* allocate module object */
    if ( FT_ALLOC( module,clazz->module_size ) )
      goto Exit;

    /* base initialization */
    module->library = library;
    module->memory  = memory;
    module->clazz   = (FT_Module_Class*)clazz;

    /* check whether the module is a renderer - this must be performed */
    /* before the normal module initialization                         */
    if ( FT_MODULE_IS_RENDERER( module ) )
    {
      /* add to the renderers list */
      error = ft_add_renderer( module );
      if ( error )
        goto Fail;
    }

    /* is the module a auto-hinter? */
    if ( FT_MODULE_IS_HINTER( module ) )
      library->auto_hinter = module;

    /* if the module is a font driver */
    if ( FT_MODULE_IS_DRIVER( module ) )
    {
      /* allocate glyph loader if needed */
      FT_Driver  driver = FT_DRIVER( module );


      driver->clazz = (FT_Driver_Class)module->clazz;
      if ( FT_DRIVER_USES_OUTLINES( driver ) )
      {
        error = FT_GlyphLoader_New( memory, &driver->glyph_loader );
        if ( error )
          goto Fail;
      }
    }

    if ( clazz->module_init )
    {
      error = clazz->module_init( module );
      if ( error )
        goto Fail;
    }

    /* add module to the library's table */
    library->modules[library->num_modules++] = module;

  Exit:
    return error;

  Fail:
    if ( FT_MODULE_IS_DRIVER( module ) )
    {
      FT_Driver  driver = FT_DRIVER( module );


      if ( FT_DRIVER_USES_OUTLINES( driver ) )
        FT_GlyphLoader_Done( driver->glyph_loader );
    }

    if ( FT_MODULE_IS_RENDERER( module ) )
    {
      FT_Renderer  renderer = FT_RENDERER( module );


      if ( renderer->raster )
        renderer->clazz->raster_class->raster_done( renderer->raster );
    }

    FT_FREE( module );
    goto Exit;
  }


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( FT_Module )
  FT_Get_Module( FT_Library   library,
                 const char*  module_name )
  {
    FT_Module   result = 0;
    FT_Module*  cur;
    FT_Module*  limit;


    if ( !library || !module_name )
      return result;

    cur   = library->modules;
    limit = cur + library->num_modules;

    for ( ; cur < limit; cur++ )
      if ( ft_strcmp( cur[0]->clazz->module_name, module_name ) == 0 )
      {
        result = cur[0];
        break;
      }

    return result;
  }


  /* documentation is in ftobjs.h */

  FT_BASE_DEF( const void* )
  FT_Get_Module_Interface( FT_Library   library,
                           const char*  mod_name )
  {
    FT_Module  module;


    /* test for valid `library' delayed to FT_Get_Module() */

    module = FT_Get_Module( library, mod_name );

    return module ? module->clazz->module_interface : 0;
  }


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Remove_Module( FT_Library  library,
                    FT_Module   module )
  {
    /* try to find the module from the table, then remove it from there */

    if ( !library )
      return FT_Err_Invalid_Library_Handle;

    if ( module )
    {
      FT_Module*  cur   = library->modules;
      FT_Module*  limit = cur + library->num_modules;


      for ( ; cur < limit; cur++ )
      {
        if ( cur[0] == module )
        {
          /* remove it from the table */
          library->num_modules--;
          limit--;
          while ( cur < limit )
          {
            cur[0] = cur[1];
            cur++;
          }
          limit[0] = 0;

          /* destroy the module */
          Destroy_Module( module );

          return FT_Err_Ok;
        }
      }
    }
    return FT_Err_Invalid_Driver_Handle;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /****                                                                 ****/
  /****                                                                 ****/
  /****                         L I B R A R Y                           ****/
  /****                                                                 ****/
  /****                                                                 ****/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( FT_Error )
  FT_New_Library( FT_Memory    memory,
                  FT_Library  *alibrary )
  {
    FT_Library  library = 0;
    FT_Error    error;


    if ( !memory )
      return FT_Err_Invalid_Argument;

#ifdef FT_DEBUG_LEVEL_ERROR
    /* init debugging support */
    ft_debug_init();
#endif

    /* first of all, allocate the library object */
    if ( FT_NEW( library ) )
      return error;

    library->memory = memory;

    /* allocate the render pool */
    library->raster_pool_size = FT_RENDER_POOL_SIZE;
    if ( FT_ALLOC( library->raster_pool, FT_RENDER_POOL_SIZE ) )
      goto Fail;

    /* That's ok now */
    *alibrary = library;

    return FT_Err_Ok;

  Fail:
    FT_FREE( library );
    return error;
  }


  /* documentation is in freetype.h */

  FT_EXPORT_DEF( void )
  FT_Library_Version( FT_Library   library,
                      FT_Int      *amajor,
                      FT_Int      *aminor,
                      FT_Int      *apatch )
  {
    FT_Int  major = 0;
    FT_Int  minor = 0;
    FT_Int  patch = 0;


    if ( library )
    {
      major = library->version_major;
      minor = library->version_minor;
      patch = library->version_patch;
    }

    if ( *amajor )
      *amajor = major;

    if ( *aminor )
      *aminor = minor;

    if ( *apatch )
      *apatch = patch;
  }


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( FT_Error )
  FT_Done_Library( FT_Library  library )
  {
    FT_Memory  memory;


    if ( !library )
      return FT_Err_Invalid_Library_Handle;

    memory = library->memory;

    /* Discard client-data */
    if ( library->generic.finalizer )
      library->generic.finalizer( library );

    /* Close all modules in the library */
#if 1
    while ( library->num_modules > 0 )
      FT_Remove_Module( library, library->modules[0] );
#else
    {
      FT_UInt  n;


      for ( n = 0; n < library->num_modules; n++ )
      {
        FT_Module  module = library->modules[n];


        if ( module )
        {
          Destroy_Module( module );
          library->modules[n] = 0;
        }
      }
    }
#endif

    /* Destroy raster objects */
    FT_FREE( library->raster_pool );
    library->raster_pool_size = 0;

    FT_FREE( library );
    return FT_Err_Ok;
  }


  /* documentation is in ftmodule.h */

  FT_EXPORT_DEF( void )
  FT_Set_Debug_Hook( FT_Library         library,
                     FT_UInt            hook_index,
                     FT_DebugHook_Func  debug_hook )
  {
    if ( library && debug_hook &&
         hook_index <
           ( sizeof ( library->debug_hooks ) / sizeof ( void* ) ) )
      library->debug_hooks[hook_index] = debug_hook;
  }


/* END */