/***************************************************************************/ /* */ /* ftdriver.h */ /* */ /* FreeType font driver interface (specification). */ /* */ /* Copyright 1996-2017 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 #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 ); /*************************************************************************/ /* */ /* */ /* FT_Driver_ClassRec */ /* */ /* */ /* The font driver class. This structure mostly contains pointers to */ /* driver methods. */ /* */ /* */ /* 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. */ /* */ /* 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; /*************************************************************************/ /* */ /* */ /* FT_DECLARE_DRIVER */ /* */ /* */ /* Used to create a forward declaration of an FT_Driver_ClassRec */ /* struct instance. */ /* */ /* */ /* FT_DEFINE_DRIVER */ /* */ /* */ /* 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. */ /* */ /* `ftinit.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 */