197 lines
5.4 KiB
C
197 lines
5.4 KiB
C
/****************************************************************************
|
|
*
|
|
* ftadvanc.h
|
|
*
|
|
* Quick computation of advance widths (specification only).
|
|
*
|
|
* Copyright 2008-2018 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 FTADVANC_H_
|
|
#define FTADVANC_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:
|
|
* quick_advance
|
|
*
|
|
* @title:
|
|
* Quick retrieval of advance values
|
|
*
|
|
* @abstract:
|
|
* Retrieve horizontal and vertical advance values without processing
|
|
* glyph outlines, if possible.
|
|
*
|
|
* @description:
|
|
* This section contains functions to quickly extract advance values
|
|
* without handling glyph outlines, if possible.
|
|
*
|
|
* @order:
|
|
* FT_Get_Advance
|
|
* FT_Get_Advances
|
|
*
|
|
*/
|
|
|
|
|
|
/**************************************************************************
|
|
*
|
|
* @enum:
|
|
* FT_ADVANCE_FLAG_FAST_ONLY
|
|
*
|
|
* @description:
|
|
* A bit-flag to be OR-ed with the `flags' parameter of the
|
|
* @FT_Get_Advance and @FT_Get_Advances functions.
|
|
*
|
|
* If set, it indicates that you want these functions to fail if the
|
|
* corresponding hinting mode or font driver doesn't allow for very
|
|
* quick advance computation.
|
|
*
|
|
* Typically, glyphs that are either unscaled, unhinted, bitmapped,
|
|
* or light-hinted can have their advance width computed very
|
|
* quickly.
|
|
*
|
|
* Normal and bytecode hinted modes that require loading, scaling,
|
|
* and hinting of the glyph outline, are extremely slow by
|
|
* comparison.
|
|
*/
|
|
#define FT_ADVANCE_FLAG_FAST_ONLY 0x20000000L
|
|
|
|
|
|
/**************************************************************************
|
|
*
|
|
* @function:
|
|
* FT_Get_Advance
|
|
*
|
|
* @description:
|
|
* Retrieve the advance value of a given glyph outline in an
|
|
* @FT_Face.
|
|
*
|
|
* @input:
|
|
* face ::
|
|
* The source @FT_Face handle.
|
|
*
|
|
* gindex ::
|
|
* The glyph index.
|
|
*
|
|
* load_flags ::
|
|
* A set of bit flags similar to those used when
|
|
* calling @FT_Load_Glyph, used to determine what kind
|
|
* of advances you need.
|
|
* @output:
|
|
* padvance ::
|
|
* The advance value. If scaling is performed (based on
|
|
* the value of `load_flags'), the advance value is in
|
|
* 16.16 format. Otherwise, it is in font units.
|
|
*
|
|
* If @FT_LOAD_VERTICAL_LAYOUT is set, this is the
|
|
* vertical advance corresponding to a vertical layout.
|
|
* Otherwise, it is the horizontal advance in a
|
|
* horizontal layout.
|
|
*
|
|
* @return:
|
|
* FreeType error code. 0 means success.
|
|
*
|
|
* @note:
|
|
* This function may fail if you use @FT_ADVANCE_FLAG_FAST_ONLY and
|
|
* if the corresponding font backend doesn't have a quick way to
|
|
* retrieve the advances.
|
|
*
|
|
* A scaled advance is returned in 16.16 format but isn't transformed
|
|
* by the affine transformation specified by @FT_Set_Transform.
|
|
*/
|
|
FT_EXPORT( FT_Error )
|
|
FT_Get_Advance( FT_Face face,
|
|
FT_UInt gindex,
|
|
FT_Int32 load_flags,
|
|
FT_Fixed *padvance );
|
|
|
|
|
|
/**************************************************************************
|
|
*
|
|
* @function:
|
|
* FT_Get_Advances
|
|
*
|
|
* @description:
|
|
* Retrieve the advance values of several glyph outlines in an
|
|
* @FT_Face.
|
|
*
|
|
* @input:
|
|
* face ::
|
|
* The source @FT_Face handle.
|
|
*
|
|
* start ::
|
|
* The first glyph index.
|
|
*
|
|
* count ::
|
|
* The number of advance values you want to retrieve.
|
|
*
|
|
* load_flags ::
|
|
* A set of bit flags similar to those used when
|
|
* calling @FT_Load_Glyph.
|
|
*
|
|
* @output:
|
|
* padvance ::
|
|
* The advance values. This array, to be provided by the
|
|
* caller, must contain at least `count' elements.
|
|
*
|
|
* If scaling is performed (based on the value of
|
|
* `load_flags'), the advance values are in 16.16 format.
|
|
* Otherwise, they are in font units.
|
|
*
|
|
* If @FT_LOAD_VERTICAL_LAYOUT is set, these are the
|
|
* vertical advances corresponding to a vertical layout.
|
|
* Otherwise, they are the horizontal advances in a
|
|
* horizontal layout.
|
|
*
|
|
* @return:
|
|
* FreeType error code. 0 means success.
|
|
*
|
|
* @note:
|
|
* This function may fail if you use @FT_ADVANCE_FLAG_FAST_ONLY and
|
|
* if the corresponding font backend doesn't have a quick way to
|
|
* retrieve the advances.
|
|
*
|
|
* Scaled advances are returned in 16.16 format but aren't
|
|
* transformed by the affine transformation specified by
|
|
* @FT_Set_Transform.
|
|
*/
|
|
FT_EXPORT( FT_Error )
|
|
FT_Get_Advances( FT_Face face,
|
|
FT_UInt start,
|
|
FT_UInt count,
|
|
FT_Int32 load_flags,
|
|
FT_Fixed *padvances );
|
|
|
|
/* */
|
|
|
|
|
|
FT_END_HEADER
|
|
|
|
#endif /* FTADVANC_H_ */
|
|
|
|
|
|
/* END */
|