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/****************************************************************************
*
* aflatin.h
*
* Auto-fitter hinting routines for latin writing system
* (specification).
*
* Copyright (C) 2003-2024 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 AFLATIN_H_
#define AFLATIN_H_
#include "afhints.h"
FT_BEGIN_HEADER
/* the `latin' writing system */
AF_DECLARE_WRITING_SYSTEM_CLASS( af_latin_writing_system_class )
/* constants are given with units_per_em == 2048 in mind */
#define AF_LATIN_CONSTANT( metrics, c ) \
( ( (c) * (FT_Long)( (AF_LatinMetrics)(metrics) )->units_per_em ) / 2048 )
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** L A T I N G L O B A L M E T R I C S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* The following declarations could be embedded in the file `aflatin.c';
* they have been made semi-public to allow alternate writing system
* hinters to re-use some of them.
*/
#define AF_LATIN_IS_TOP_BLUE( b ) \
( (b)->properties & AF_BLUE_PROPERTY_LATIN_TOP )
#define AF_LATIN_IS_SUB_TOP_BLUE( b ) \
( (b)->properties & AF_BLUE_PROPERTY_LATIN_SUB_TOP )
#define AF_LATIN_IS_NEUTRAL_BLUE( b ) \
( (b)->properties & AF_BLUE_PROPERTY_LATIN_NEUTRAL )
#define AF_LATIN_IS_X_HEIGHT_BLUE( b ) \
( (b)->properties & AF_BLUE_PROPERTY_LATIN_X_HEIGHT )
#define AF_LATIN_IS_LONG_BLUE( b ) \
( (b)->properties & AF_BLUE_PROPERTY_LATIN_LONG )
#define AF_LATIN_MAX_WIDTHS 16
#define AF_LATIN_BLUE_ACTIVE ( 1U << 0 ) /* zone height is <= 3/4px */
#define AF_LATIN_BLUE_TOP ( 1U << 1 ) /* we have a top blue zone */
#define AF_LATIN_BLUE_SUB_TOP ( 1U << 2 ) /* we have a subscript top */
/* blue zone */
#define AF_LATIN_BLUE_NEUTRAL ( 1U << 3 ) /* we have neutral blue zone */
#define AF_LATIN_BLUE_ADJUSTMENT ( 1U << 4 ) /* used for scale adjustment */
/* optimization */
typedef struct AF_LatinBlueRec_
{
AF_WidthRec ref;
AF_WidthRec shoot;
FT_Pos ascender;
FT_Pos descender;
FT_UInt flags;
} AF_LatinBlueRec, *AF_LatinBlue;
typedef struct AF_LatinAxisRec_
{
FT_Fixed scale;
FT_Pos delta;
FT_UInt width_count; /* number of used widths */
AF_WidthRec widths[AF_LATIN_MAX_WIDTHS]; /* widths array */
FT_Pos edge_distance_threshold; /* used for creating edges */
FT_Pos standard_width; /* the default stem thickness */
FT_Bool extra_light; /* is standard width very light? */
/* ignored for horizontal metrics */
FT_UInt blue_count;
AF_LatinBlueRec blues[AF_BLUE_STRINGSET_MAX_LEN];
FT_Fixed org_scale;
FT_Pos org_delta;
} AF_LatinAxisRec, *AF_LatinAxis;
typedef struct AF_LatinMetricsRec_
{
AF_StyleMetricsRec root;
FT_UInt units_per_em;
AF_LatinAxisRec axis[AF_DIMENSION_MAX];
} AF_LatinMetricsRec, *AF_LatinMetrics;
FT_LOCAL( FT_Error )
af_latin_metrics_init( AF_StyleMetrics metrics,
FT_Face face );
FT_LOCAL( void )
af_latin_metrics_scale( AF_StyleMetrics metrics,
AF_Scaler scaler );
FT_LOCAL( void )
af_latin_metrics_init_widths( AF_LatinMetrics metrics,
FT_Face face );
FT_LOCAL( void )
af_latin_metrics_check_digits( AF_LatinMetrics metrics,
FT_Face face );
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** L A T I N G L Y P H A N A L Y S I S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define AF_LATIN_HINTS_HORZ_SNAP ( 1U << 0 ) /* stem width snapping */
#define AF_LATIN_HINTS_VERT_SNAP ( 1U << 1 ) /* stem height snapping */
#define AF_LATIN_HINTS_STEM_ADJUST ( 1U << 2 ) /* stem width/height */
/* adjustment */
#define AF_LATIN_HINTS_MONO ( 1U << 3 ) /* monochrome rendering */
#define AF_LATIN_HINTS_DO_HORZ_SNAP( h ) \
AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_HORZ_SNAP )
#define AF_LATIN_HINTS_DO_VERT_SNAP( h ) \
AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_VERT_SNAP )
#define AF_LATIN_HINTS_DO_STEM_ADJUST( h ) \
AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_STEM_ADJUST )
#define AF_LATIN_HINTS_DO_MONO( h ) \
AF_HINTS_TEST_OTHER( h, AF_LATIN_HINTS_MONO )
/*
* The next functions shouldn't normally be exported. However, other
* writing systems might like to use these functions as-is.
*/
FT_LOCAL( FT_Error )
af_latin_hints_compute_segments( AF_GlyphHints hints,
AF_Dimension dim );
FT_LOCAL( void )
af_latin_hints_link_segments( AF_GlyphHints hints,
FT_UInt width_count,
AF_WidthRec* widths,
AF_Dimension dim );
FT_LOCAL( FT_Error )
af_latin_hints_compute_edges( AF_GlyphHints hints,
AF_Dimension dim );
FT_LOCAL( FT_Error )
af_latin_hints_detect_features( AF_GlyphHints hints,
FT_UInt width_count,
AF_WidthRec* widths,
AF_Dimension dim );
/* */
FT_END_HEADER
#endif /* AFLATIN_H_ */
/* END */