freetype2/include/internal/ftdriver.h

410 lines
21 KiB
C

/***************************************************************************/
/* */
/* ftdriver.h */
/* */
/* FreeType font driver interface (specification). */
/* */
/* Copyright 1996-2015 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 __FTDRIVER_H__
#define __FTDRIVER_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_UInt
(*FT_CharMap_CharIndexFunc)( FT_CharMap charmap,
FT_Long charcode );
typedef FT_Long
(*FT_CharMap_CharNextFunc)( FT_CharMap charmap,
FT_Long charcode );
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. */
/* */
/* When FT_CONFIG_OPTION_PIC is defined a `create' function has to be */
/* called with a pointer where the allocated structure is returned. */
/* And when it is no longer needed a `destroy' function needs to be */
/* called to release that allocation. */
/* */
/* `fcinit.c' (ft_create_default_module_classes) already contains a */
/* mechanism to call these functions for the default modules */
/* described in `ftmodule.h'. */
/* */
/* Notice that the created `create' and `destroy' functions call */
/* `pic_init' and `pic_free' to allow you to manually allocate and */
/* initialize any additional global data, like a module specific */
/* interface, and put them in the global pic container defined in */
/* `ftpic.h'. If you don't need them just implement the functions as */
/* empty to resolve the link error. Also the `pic_init' and */
/* `pic_free' functions should be declared in `pic.h', to be referred */
/* by driver definition calling `FT_DEFINE_DRIVER' in following. */
/* */
/* When FT_CONFIG_OPTION_PIC is not defined the struct will be */
/* allocated in the global scope (or the scope where the macro is */
/* used). */
/* */
#ifndef FT_CONFIG_OPTION_PIC
#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_ \
};
#else /* FT_CONFIG_OPTION_PIC */
#define FT_DECLARE_DRIVER( class_ ) FT_DECLARE_MODULE( 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_ ) \
void \
FT_Destroy_Class_ ## class_( FT_Library library, \
FT_Module_Class* clazz ) \
{ \
FT_Memory memory = library->memory; \
FT_Driver_Class dclazz = (FT_Driver_Class)clazz; \
\
\
class_ ## _pic_free( library ); \
if ( dclazz ) \
FT_FREE( dclazz ); \
} \
\
\
FT_Error \
FT_Create_Class_ ## class_( FT_Library library, \
FT_Module_Class** output_class ) \
{ \
FT_Driver_Class clazz = NULL; \
FT_Error error; \
FT_Memory memory = library->memory; \
\
\
if ( FT_ALLOC( clazz, sizeof ( *clazz ) ) ) \
return error; \
\
error = class_ ## _pic_init( library ); \
if ( error ) \
{ \
FT_FREE( clazz ); \
return error; \
} \
\
FT_DEFINE_ROOT_MODULE( flags_, \
size_, \
name_, \
version_, \
requires_, \
interface_, \
init_, \
done_, \
get_interface_ ) \
\
clazz->face_object_size = face_object_size_; \
clazz->size_object_size = size_object_size_; \
clazz->slot_object_size = slot_object_size_; \
\
clazz->init_face = init_face_; \
clazz->done_face = done_face_; \
\
clazz->init_size = init_size_; \
clazz->done_size = done_size_; \
\
clazz->init_slot = init_slot_; \
clazz->done_slot = done_slot_; \
\
clazz->load_glyph = load_glyph_; \
\
clazz->get_kerning = get_kerning_; \
clazz->attach_file = attach_file_; \
clazz->get_advances = get_advances_; \
\
clazz->request_size = request_size_; \
clazz->select_size = select_size_; \
\
*output_class = (FT_Module_Class*)clazz; \
\
return FT_Err_Ok; \
}
#endif /* FT_CONFIG_OPTION_PIC */
FT_END_HEADER
#endif /* __FTDRIVER_H__ */
/* END */