289 lines
9.0 KiB
C
289 lines
9.0 KiB
C
/****************************************************************************
|
|
*
|
|
* ftdrv.h
|
|
*
|
|
* FreeType internal font driver interface (specification).
|
|
*
|
|
* Copyright (C) 1996-2020 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 <ft2build.h>
|
|
#include FT_MODULE_H
|
|
|
|
|
|
FT_BEGIN_HEADER
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Face_InitFunc)( FT_Stream stream,
|
|
FT_Face face,
|
|
FT_Int typeface_index,
|
|
FT_Int num_params,
|
|
FT_Parameter* parameters );
|
|
|
|
typedef void
|
|
(*FT_Face_DoneFunc)( FT_Face face );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Size_InitFunc)( FT_Size size );
|
|
|
|
typedef void
|
|
(*FT_Size_DoneFunc)( FT_Size size );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Slot_InitFunc)( FT_GlyphSlot slot );
|
|
|
|
typedef void
|
|
(*FT_Slot_DoneFunc)( FT_GlyphSlot slot );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Size_RequestFunc)( FT_Size size,
|
|
FT_Size_Request req );
|
|
|
|
typedef FT_Error
|
|
(*FT_Size_SelectFunc)( FT_Size size,
|
|
FT_ULong size_index );
|
|
|
|
typedef FT_Error
|
|
(*FT_Slot_LoadFunc)( FT_GlyphSlot slot,
|
|
FT_Size size,
|
|
FT_UInt glyph_index,
|
|
FT_Int32 load_flags );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Face_GetKerningFunc)( FT_Face face,
|
|
FT_UInt left_glyph,
|
|
FT_UInt right_glyph,
|
|
FT_Vector* kerning );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Face_AttachFunc)( FT_Face face,
|
|
FT_Stream stream );
|
|
|
|
|
|
typedef FT_Error
|
|
(*FT_Face_GetAdvancesFunc)( FT_Face face,
|
|
FT_UInt first,
|
|
FT_UInt count,
|
|
FT_Int32 flags,
|
|
FT_Fixed* advances );
|
|
|
|
|
|
/**************************************************************************
|
|
*
|
|
* @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.
|
|
*/
|
|
typedef struct FT_Driver_ClassRec_
|
|
{
|
|
FT_Module_Class root;
|
|
|
|
FT_Long face_object_size;
|
|
FT_Long size_object_size;
|
|
FT_Long slot_object_size;
|
|
|
|
FT_Face_InitFunc init_face;
|
|
FT_Face_DoneFunc done_face;
|
|
|
|
FT_Size_InitFunc init_size;
|
|
FT_Size_DoneFunc done_size;
|
|
|
|
FT_Slot_InitFunc init_slot;
|
|
FT_Slot_DoneFunc done_slot;
|
|
|
|
FT_Slot_LoadFunc load_glyph;
|
|
|
|
FT_Face_GetKerningFunc get_kerning;
|
|
FT_Face_AttachFunc attach_file;
|
|
FT_Face_GetAdvancesFunc get_advances;
|
|
|
|
/* since version 2.2 */
|
|
FT_Size_RequestFunc request_size;
|
|
FT_Size_SelectFunc select_size;
|
|
|
|
} FT_Driver_ClassRec, *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_ ) \
|
|
FT_CALLBACK_TABLE \
|
|
const FT_Driver_ClassRec 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_CALLBACK_TABLE_DEF \
|
|
const FT_Driver_ClassRec class_ = \
|
|
{ \
|
|
FT_DEFINE_ROOT_MODULE( 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 */
|