godot/thirdparty/freetype/include/freetype/internal/ftdrv.h

/****************************************************************************
 *
 * ftdrv.h
 *
 *   FreeType internal font driver interface (specification).
 *
 * Copyright (C) 1996-2023 by
 * David Turner, Robert Wilhelm, and Werner Lemberg.
 *
 * 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.
 *
 */


#ifndef FTDRV_H_
#define FTDRV_H_


#include <freetype/ftmodapi.h>

#include "compiler-macros.h"

FT_BEGIN_HEADER


  FT_Face_InitFunc;

  FT_Face_DoneFunc;


  FT_Size_InitFunc;

  FT_Size_DoneFunc;


  FT_Slot_InitFunc;

  FT_Slot_DoneFunc;


  FT_Size_RequestFunc;

  FT_Size_SelectFunc;

  FT_Slot_LoadFunc;


  FT_Face_GetKerningFunc;


  FT_Face_AttachFunc;


  FT_Face_GetAdvancesFunc;


  /**************************************************************************
   *
   * @struct:
   *   FT_Driver_ClassRec
   *
   * @description:
   *   The font driver class.  This structure mostly contains pointers to
   *   driver methods.
   *
   * @fields:
   *   root ::
   *     The parent module.
   *
   *   face_object_size ::
   *     The size of a face object in bytes.
   *
   *   size_object_size ::
   *     The size of a size object in bytes.
   *
   *   slot_object_size ::
   *     The size of a glyph object in bytes.
   *
   *   init_face ::
   *     The format-specific face constructor.
   *
   *   done_face ::
   *     The format-specific face destructor.
   *
   *   init_size ::
   *     The format-specific size constructor.
   *
   *   done_size ::
   *     The format-specific size destructor.
   *
   *   init_slot ::
   *     The format-specific slot constructor.
   *
   *   done_slot ::
   *     The format-specific slot destructor.
   *
   *
   *   load_glyph ::
   *     A function handle to load a glyph to a slot.  This field is
   *     mandatory!
   *
   *   get_kerning ::
   *     A function handle to return the unscaled kerning for a given pair of
   *     glyphs.  Can be set to 0 if the format doesn't support kerning.
   *
   *   attach_file ::
   *     This function handle is used to read additional data for a face from
   *     another file/stream.  For example, this can be used to add data from
   *     AFM or PFM files on a Type 1 face, or a CIDMap on a CID-keyed face.
   *
   *   get_advances ::
   *     A function handle used to return advance widths of 'count' glyphs
   *     (in font units), starting at 'first'.  The 'vertical' flag must be
   *     set to get vertical advance heights.  The 'advances' buffer is
   *     caller-allocated.  The idea of this function is to be able to
   *     perform device-independent text layout without loading a single
   *     glyph image.
   *
   *   request_size ::
   *     A handle to a function used to request the new character size.  Can
   *     be set to 0 if the scaling done in the base layer suffices.
   *
   *   select_size ::
   *     A handle to a function used to select a new fixed size.  It is used
   *     only if @FT_FACE_FLAG_FIXED_SIZES is set.  Can be set to 0 if the
   *     scaling done in the base layer suffices.
   *
   * @note:
   *   Most function pointers, with the exception of `load_glyph`, can be set
   *   to 0 to indicate a default behaviour.
   */
  FT_Driver_Class;


  /**************************************************************************
   *
   * @macro:
   *   FT_DECLARE_DRIVER
   *
   * @description:
   *   Used to create a forward declaration of an FT_Driver_ClassRec struct
   *   instance.
   *
   * @macro:
   *   FT_DEFINE_DRIVER
   *
   * @description:
   *   Used to initialize an instance of FT_Driver_ClassRec struct.
   *
   *   `ftinit.c` (ft_create_default_module_classes) already contains a
   *   mechanism to call these functions for the default modules described in
   *   `ftmodule.h`.
   *
   *   The struct will be allocated in the global scope (or the scope where
   *   the macro is used).
   */
#define FT_DECLARE_DRIVER( class_ ) …

#define FT_DEFINE_DRIVER(                    \
          class_,                            \
          flags_,                            \
          size_,                             \
          name_,                             \
          version_,                          \
          requires_,                         \
          interface_,                        \
          init_,                             \
          done_,                             \
          get_interface_,                    \
          face_object_size_,                 \
          size_object_size_,                 \
          slot_object_size_,                 \
          init_face_,                        \
          done_face_,                        \
          init_size_,                        \
          done_size_,                        \
          init_slot_,                        \
          done_slot_,                        \
          load_glyph_,                       \
          get_kerning_,                      \
          attach_file_,                      \
          get_advances_,                     \
          request_size_,                     \
          select_size_ ) …


FT_END_HEADER

#endif /* FTDRV_H_ */


/* END */