freetype2/include/freetype/ftbdf.h

214 lines
5.2 KiB
C

/****************************************************************************
*
* ftbdf.h
*
* FreeType API for accessing BDF-specific strings (specification).
*
* Copyright 2002-2019 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 FTBDF_H_
#define FTBDF_H_
#include <ft2build.h>
#include FT_FREETYPE_H
#ifdef FREETYPE_H
#error "freetype.h of FreeType 1 has been loaded!"
#error "Please fix the directory search order for header files"
#error "so that freetype.h of FreeType 2 is found first."
#endif
FT_BEGIN_HEADER
/**************************************************************************
*
* @section:
* bdf_fonts
*
* @title:
* BDF and PCF Files
*
* @abstract:
* BDF and PCF specific API.
*
* @description:
* This section contains the declaration of functions specific to BDF and
* PCF fonts.
*
*/
/**************************************************************************
*
* @enum:
* BDF_PropertyType
*
* @description:
* A list of BDF property types.
*
* @values:
* BDF_PROPERTY_TYPE_NONE ::
* Value~0 is used to indicate a missing property.
*
* BDF_PROPERTY_TYPE_ATOM ::
* Property is a string atom.
*
* BDF_PROPERTY_TYPE_INTEGER ::
* Property is a 32-bit signed integer.
*
* BDF_PROPERTY_TYPE_CARDINAL ::
* Property is a 32-bit unsigned integer.
*/
typedef enum BDF_PropertyType_
{
BDF_PROPERTY_TYPE_NONE = 0,
BDF_PROPERTY_TYPE_ATOM = 1,
BDF_PROPERTY_TYPE_INTEGER = 2,
BDF_PROPERTY_TYPE_CARDINAL = 3
} BDF_PropertyType;
/**************************************************************************
*
* @type:
* BDF_Property
*
* @description:
* A handle to a @BDF_PropertyRec structure to model a given BDF/PCF
* property.
*/
typedef struct BDF_PropertyRec_* BDF_Property;
/**************************************************************************
*
* @struct:
* BDF_PropertyRec
*
* @description:
* This structure models a given BDF/PCF property.
*
* @fields:
* type ::
* The property type.
*
* u.atom ::
* The atom string, if type is @BDF_PROPERTY_TYPE_ATOM. May be NULL,
* indicating an empty string.
*
* u.integer ::
* A signed integer, if type is @BDF_PROPERTY_TYPE_INTEGER.
*
* u.cardinal ::
* An unsigned integer, if type is @BDF_PROPERTY_TYPE_CARDINAL.
*/
typedef struct BDF_PropertyRec_
{
BDF_PropertyType type;
union {
const char* atom;
FT_Int32 integer;
FT_UInt32 cardinal;
} u;
} BDF_PropertyRec;
/**************************************************************************
*
* @function:
* FT_Get_BDF_Charset_ID
*
* @description:
* Retrieve a BDF font character set identity, according to the BDF
* specification.
*
* @input:
* face ::
* A handle to the input face.
*
* @output:
* acharset_encoding ::
* Charset encoding, as a C~string, owned by the face.
*
* acharset_registry ::
* Charset registry, as a C~string, owned by the face.
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* This function only works with BDF faces, returning an error otherwise.
*/
FT_EXPORT( FT_Error )
FT_Get_BDF_Charset_ID( FT_Face face,
const char* *acharset_encoding,
const char* *acharset_registry );
/**************************************************************************
*
* @function:
* FT_Get_BDF_Property
*
* @description:
* Retrieve a BDF property from a BDF or PCF font file.
*
* @input:
* face ::
* A handle to the input face.
*
* name ::
* The property name.
*
* @output:
* aproperty ::
* The property.
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* This function works with BDF _and_ PCF fonts. It returns an error
* otherwise. It also returns an error if the property is not in the
* font.
*
* A 'property' is a either key-value pair within the STARTPROPERTIES
* ... ENDPROPERTIES block of a BDF font or a key-value pair from the
* `info->props` array within a `FontRec` structure of a PCF font.
*
* Integer properties are always stored as 'signed' within PCF fonts;
* consequently, @BDF_PROPERTY_TYPE_CARDINAL is a possible return value
* for BDF fonts only.
*
* In case of error, `aproperty->type` is always set to
* @BDF_PROPERTY_TYPE_NONE.
*/
FT_EXPORT( FT_Error )
FT_Get_BDF_Property( FT_Face face,
const char* prop_name,
BDF_PropertyRec *aproperty );
/* */
FT_END_HEADER
#endif /* FTBDF_H_ */
/* END */