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/***************************************************************************/
/* */
/* cf2hints.h */
/* */
/* Adobe's code for handling CFF hints (body). */
/* */
/* Copyright 2007-2013 Adobe Systems Incorporated. */
/* */
/* This software, and all works of authorship, whether in source or */
/* object code form as indicated by the copyright notice(s) included */
/* herein (collectively, the "Work") is made available, and may only be */
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/* FreeType Project License, each contributor to the Work hereby grants */
/* to any individual or legal entity exercising permissions granted by */
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/* (including a cross-claim or counterclaim in a lawsuit) alleging that */
/* the Work or a contribution incorporated within the Work constitutes */
/* direct or contributory patent infringement, then any patent licenses */
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/* the date such litigation is filed. */
/* */
/* By using, modifying, or distributing the Work you indicate that you */
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/***************************************************************************/
#ifndef __CF2HINTS_H__
#define __CF2HINTS_H__
FT_BEGIN_HEADER
enum
{
CF2_MAX_HINTS = 96 /* maximum # of hints */
};
/*
* A HintMask object stores a bit mask that specifies which hints in the
* charstring are active at a given time. Hints in CFF must be declared
* at the start, before any drawing operators, with horizontal hints
* preceding vertical hints. The HintMask is ordered the same way, with
* horizontal hints immediately followed by vertical hints. Clients are
* responsible for knowing how many of each type are present.
*
* The maximum total number of hints is 96, as specified by the CFF
* specification.
*
* A HintMask is built 0 or more times while interpreting a charstring, by
* the HintMask operator. There is only one HintMask, but it is built or
* rebuilt each time there is a hint substitution (HintMask operator) in
* the charstring. A default HintMask with all bits set is built if there
* has been no HintMask operator prior to the first drawing operator.
*
*/
typedef struct CF2_HintMaskRec_
{
FT_Error* error;
FT_Bool isValid;
FT_Bool isNew;
size_t bitCount;
size_t byteCount;
FT_Byte mask[( CF2_MAX_HINTS + 7 ) / 8];
} CF2_HintMaskRec, *CF2_HintMask;
typedef struct CF2_StemHintRec_
{
FT_Bool used; /* DS positions are valid */
CF2_Fixed min; /* original character space value */
CF2_Fixed max;
CF2_Fixed minDS; /* DS position after first use */
CF2_Fixed maxDS;
} CF2_StemHintRec, *CF2_StemHint;
/*
* A HintMap object stores a piecewise linear function for mapping
* y-coordinates from character space to device space, providing
* appropriate pixel alignment to stem edges.
*
* The map is implemented as an array of `CF2_Hint' elements, each
* representing an edge. When edges are paired, as from stem hints, the
* bottom edge must immediately precede the top edge in the array.
* Element character space AND device space positions must both increase
* monotonically in the array. `CF2_Hint' elements are also used as
* parameters to `cf2_blues_capture'.
*
* The `cf2_hintmap_build' method must be called before any drawing
* operation (beginning with a Move operator) and at each hint
* substitution (HintMask operator).
*
* The `cf2_hintmap_map' method is called to transform y-coordinates at
* each drawing operation (move, line, curve).
*
*/
/* TODO: make this a CF2_ArrStack and add a deep copy method */
enum
{
CF2_MAX_HINT_EDGES = CF2_MAX_HINTS * 2
};
typedef struct CF2_HintMapRec_
{
CF2_Font font;
/* initial map based on blue zones */
struct CF2_HintMapRec_* initialHintMap;
/* working storage for 2nd pass adjustHints */
CF2_ArrStack hintMoves;
FT_Bool isValid;
FT_Bool hinted;
CF2_Fixed scale;
CF2_UInt count;
/* start search from this index */
CF2_UInt lastIndex;
CF2_HintRec edge[CF2_MAX_HINT_EDGES]; /* 192 */
} CF2_HintMapRec, *CF2_HintMap;
FT_LOCAL( FT_Bool )
cf2_hint_isValid( const CF2_Hint hint );
FT_LOCAL( FT_Bool )
cf2_hint_isTop( const CF2_Hint hint );
FT_LOCAL( FT_Bool )
cf2_hint_isBottom( const CF2_Hint hint );
FT_LOCAL( void )
cf2_hint_lock( CF2_Hint hint );
FT_LOCAL( void )
cf2_hintmap_init( CF2_HintMap hintmap,
CF2_Font font,
CF2_HintMap initialMap,
CF2_ArrStack hintMoves,
CF2_Fixed scale );
FT_LOCAL( void )
cf2_hintmap_build( CF2_HintMap hintmap,
CF2_ArrStack hStemHintArray,
CF2_ArrStack vStemHintArray,
CF2_HintMask hintMask,
CF2_Fixed hintOrigin,
FT_Bool initialMap );
/*
* GlyphPath is a wrapper for drawing operations that scales the
* coordinates according to the render matrix and HintMap. It also tracks
* open paths to control ClosePath and to insert MoveTo for broken fonts.
*
*/
typedef struct CF2_GlyphPathRec_
{
/* TODO: gather some of these into a hinting context */
CF2_Font font; /* font instance */
CF2_OutlineCallbacks callbacks; /* outline consumer */
CF2_HintMapRec hintMap; /* current hint map */
CF2_HintMapRec firstHintMap; /* saved copy */
CF2_HintMapRec initialHintMap; /* based on all captured hints */
CF2_ArrStackRec hintMoves; /* list of hint moves for 2nd pass */
CF2_Fixed scaleX; /* matrix a */
CF2_Fixed scaleC; /* matrix c */
CF2_Fixed scaleY; /* matrix d */
FT_Vector fractionalTranslation; /* including deviceXScale */
#if 0
CF2_Fixed hShift; /* character space horizontal shift */
/* (for fauxing) */
#endif
FT_Bool pathIsOpen; /* true after MoveTo */
FT_Bool darken; /* true if stem darkening */
FT_Bool moveIsPending; /* true between MoveTo and offset MoveTo */
/* references used to call `cf2_hintmap_build', if necessary */
CF2_ArrStack hStemHintArray;
CF2_ArrStack vStemHintArray;
CF2_HintMask hintMask; /* ptr to the current mask */
CF2_Fixed hintOriginY; /* copy of current origin */
const CF2_BluesRec* blues;
CF2_Fixed xOffset; /* character space offsets */
CF2_Fixed yOffset;
/* character space miter limit threshold */
CF2_Fixed miterLimit;
/* vertical/horzizontal snap distance in character space */
CF2_Fixed snapThreshold;
FT_Vector offsetStart0; /* first and second points of first */
FT_Vector offsetStart1; /* element with offset applied */
/* current point, character space, before offset */
FT_Vector currentCS;
/* current point, device space */
FT_Vector currentDS;
FT_Vector start; /* start point of subpath */
/* the following members constitute the `queue' of one element */
FT_Bool elemIsQueued;
CF2_Int prevElemOp;
FT_Vector prevElemP0;
FT_Vector prevElemP1;
FT_Vector prevElemP2;
FT_Vector prevElemP3;
} CF2_GlyphPathRec, *CF2_GlyphPath;
FT_LOCAL( void )
cf2_glyphpath_init( CF2_GlyphPath glyphpath,
CF2_Font font,
CF2_OutlineCallbacks callbacks,
CF2_Fixed scaleY,
/* CF2_Fixed hShift, */
CF2_ArrStack hStemHintArray,
CF2_ArrStack vStemHintArray,
CF2_HintMask hintMask,
CF2_Fixed hintOrigin,
const CF2_Blues blues,
const FT_Vector* fractionalTranslation );
FT_LOCAL( void )
cf2_glyphpath_finalize( CF2_GlyphPath glyphpath );
FT_LOCAL( void )
cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath,
CF2_Fixed x,
CF2_Fixed y );
FT_LOCAL( void )
cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath,
CF2_Fixed x,
CF2_Fixed y );
FT_LOCAL( void )
cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath,
CF2_Fixed x1,
CF2_Fixed y1,
CF2_Fixed x2,
CF2_Fixed y2,
CF2_Fixed x3,
CF2_Fixed y3 );
FT_LOCAL( void )
cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath );
FT_END_HEADER
#endif /* __CF2HINTS_H__ */
/* END */