ref: a2da05c2c539c603aa3587a1acb07bff8cdab599
dir: /src/autofit/aftypes.h/
/***************************************************************************/
/* */
/* aftypes.h */
/* */
/* Auto-fitter types (specification only). */
/* */
/* Copyright 2003, 2004, 2005, 2006 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. */
/* */
/***************************************************************************/
/*************************************************************************
*
* The auto-fitter is a complete rewrite of the old auto-hinter.
* Its main feature is the ability to differentiate between different
* scripts in order to apply language-specific rules.
*
* The code has also been compartimentized into several entities that
* should make algorithmic experimentation easier than with the old
* code.
*
* Finally, we get rid of the Catharon license, since this code is
* released under the FreeType one.
*
*************************************************************************/
#ifndef __AFTYPES_H__
#define __AFTYPES_H__
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_OUTLINE_H
#include FT_INTERNAL_OBJECTS_H
#include FT_INTERNAL_DEBUG_H
FT_BEGIN_HEADER
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** D E B U G G I N G *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define xxAF_USE_WARPER /* only define to use warp hinting */
#define xxAF_DEBUG
#ifdef AF_DEBUG
#include <stdio.h>
#define AF_LOG( x ) printf x
#else
#define AF_LOG( x ) do ; while ( 0 ) /* nothing */
#endif /* AF_DEBUG */
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** U T I L I T Y S T U F F *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
typedef struct AF_WidthRec_
{
FT_Pos org; /* original position/width in font units */
FT_Pos cur; /* current/scaled position/width in device sub-pixels */
FT_Pos fit; /* current/fitted position/width in device sub-pixels */
} AF_WidthRec, *AF_Width;
FT_LOCAL( void )
af_sort_pos( FT_UInt count,
FT_Pos* table );
FT_LOCAL( void )
af_sort_widths( FT_UInt count,
AF_Width widths );
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** A N G L E T Y P E S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* The auto-fitter doesn't need a very high angular accuracy;
* this allows us to speed up some computations considerably with a
* light Cordic algorithm (see afangles.c).
*/
typedef FT_Int AF_Angle;
#define AF_ANGLE_PI 256
#define AF_ANGLE_2PI ( AF_ANGLE_PI * 2 )
#define AF_ANGLE_PI2 ( AF_ANGLE_PI / 2 )
#define AF_ANGLE_PI4 ( AF_ANGLE_PI / 4 )
#if 0
/*
* compute the angle of a given 2-D vector
*/
FT_LOCAL( AF_Angle )
af_angle_atan( FT_Pos dx,
FT_Pos dy );
/*
* compute `angle2 - angle1'; the result is always within
* the range [-AF_ANGLE_PI .. AF_ANGLE_PI - 1]
*/
FT_LOCAL( AF_Angle )
af_angle_diff( AF_Angle angle1,
AF_Angle angle2 );
#endif /* 0 */
/*
* Return TRUE if a corner is flat or nearly flat. This is equivalent to
* saying that the angle difference between the `in' and `out' vectors is
* very small.
*/
FT_LOCAL( FT_Int )
af_corner_is_flat( FT_Pos x_in,
FT_Pos y_in,
FT_Pos x_out,
FT_Pos y_out );
/*
* Return -1, 0, or +1, depending on the orientation of a given corner.
* We use the Cartesian coordinate system, with positive vertical values
* going upwards. The function returns +1 when the corner turns to the
* left, -1 to the right, and 0 for undecided.
*/
FT_LOCAL( FT_Int )
af_corner_orientation( FT_Pos x_in,
FT_Pos y_in,
FT_Pos x_out,
FT_Pos y_out );
#define AF_ANGLE_DIFF( result, angle1, angle2 ) \
FT_BEGIN_STMNT \
AF_Angle _delta = (angle2) - (angle1); \
\
\
_delta %= AF_ANGLE_2PI; \
if ( _delta < 0 ) \
_delta += AF_ANGLE_2PI; \
\
if ( _delta > AF_ANGLE_PI ) \
_delta -= AF_ANGLE_2PI; \
\
result = _delta; \
FT_END_STMNT
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** O U T L I N E S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/* opaque handle to glyph-specific hints -- see `afhints.h' for more
* details
*/
typedef struct AF_GlyphHintsRec_* AF_GlyphHints;
/* This structure is used to model an input glyph outline to
* the auto-hinter. The latter will set the `hints' field
* depending on the glyph's script.
*/
typedef struct AF_OutlineRec_
{
FT_Face face;
FT_Outline outline;
FT_UInt outline_resolution;
FT_Int advance;
FT_UInt metrics_resolution;
AF_GlyphHints hints;
} AF_OutlineRec;
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** S C A L E R S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* A scaler models the target pixel device that will receive the
* auto-hinted glyph image.
*/
typedef enum
{
AF_SCALER_FLAG_NO_HORIZONTAL = 1, /* disable horizontal hinting */
AF_SCALER_FLAG_NO_VERTICAL = 2, /* disable vertical hinting */
AF_SCALER_FLAG_NO_ADVANCE = 4 /* disable advance hinting */
} AF_ScalerFlags;
typedef struct AF_ScalerRec_
{
FT_Face face; /* source font face */
FT_Fixed x_scale; /* from font units to 1/64th device pixels */
FT_Fixed y_scale; /* from font units to 1/64th device pixels */
FT_Pos x_delta; /* in 1/64th device pixels */
FT_Pos y_delta; /* in 1/64th device pixels */
FT_Render_Mode render_mode; /* monochrome, anti-aliased, LCD, etc. */
FT_UInt32 flags; /* additional control flags, see above */
} AF_ScalerRec, *AF_Scaler;
#define AF_SCALER_EQUAL_SCALES( a, b ) \
( (a)->x_scale == (b)->x_scale && \
(a)->y_scale == (b)->y_scale && \
(a)->x_delta == (b)->x_delta && \
(a)->y_delta == (b)->y_delta )
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** S C R I P T S *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*
* The list of know scripts. Each different script corresponds to the
* following information:
*
* - A set of Unicode ranges to test whether the face supports the
* script.
*
* - A specific global analyzer that will compute global metrics
* specific to the script.
*
* - A specific glyph analyzer that will compute segments and
* edges for each glyph covered by the script.
*
* - A specific grid-fitting algorithm that will distort the
* scaled glyph outline according to the results of the glyph
* analyzer.
*
* Note that a given analyzer and/or grid-fitting algorithm can be
* used by more than one script.
*/
typedef enum
{
AF_SCRIPT_NONE = 0,
AF_SCRIPT_LATIN = 1,
AF_SCRIPT_CJK = 2,
/* add new scripts here. Don't forget to update the list in */
/* `afglobal.c'. */
AF_SCRIPT_MAX /* do not remove */
} AF_Script;
typedef struct AF_ScriptClassRec_ const* AF_ScriptClass;
typedef struct AF_ScriptMetricsRec_
{
AF_ScriptClass clazz;
AF_ScalerRec scaler;
} AF_ScriptMetricsRec, *AF_ScriptMetrics;
/* This function parses an FT_Face to compute global metrics for
* a specific script.
*/
typedef FT_Error
(*AF_Script_InitMetricsFunc)( AF_ScriptMetrics metrics,
FT_Face face );
typedef void
(*AF_Script_ScaleMetricsFunc)( AF_ScriptMetrics metrics,
AF_Scaler scaler );
typedef void
(*AF_Script_DoneMetricsFunc)( AF_ScriptMetrics metrics );
typedef FT_Error
(*AF_Script_InitHintsFunc)( AF_GlyphHints hints,
AF_ScriptMetrics metrics );
typedef void
(*AF_Script_ApplyHintsFunc)( AF_GlyphHints hints,
FT_Outline* outline,
AF_ScriptMetrics metrics );
typedef struct AF_Script_UniRangeRec_
{
FT_UInt32 first;
FT_UInt32 last;
} AF_Script_UniRangeRec;
typedef const AF_Script_UniRangeRec *AF_Script_UniRange;
typedef struct AF_ScriptClassRec_
{
AF_Script script;
AF_Script_UniRange script_uni_ranges; /* last must be { 0, 0 } */
FT_UInt script_metrics_size;
AF_Script_InitMetricsFunc script_metrics_init;
AF_Script_ScaleMetricsFunc script_metrics_scale;
AF_Script_DoneMetricsFunc script_metrics_done;
AF_Script_InitHintsFunc script_hints_init;
AF_Script_ApplyHintsFunc script_hints_apply;
} AF_ScriptClassRec;
/* */
FT_END_HEADER
#endif /* __AFTYPES_H__ */
/* END */