/***************************************************************************/
/* */
/* pshints.h */
/* */
/* Interface to Postscript-specific (Type 1 and Type 2) hints */
/* recorders (specification only). These are used to support native */
/* T1/T2 hints in the `type1', `cid', and `cff' font drivers. */
/* */
/* Copyright 2001, 2002, 2003, 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. */
/* */
/***************************************************************************/
#ifndef __PSHINTS_H__
#define __PSHINTS_H__
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_TYPE1_TABLES_H
FT_BEGIN_HEADER
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** INTERNAL REPRESENTATION OF GLOBALS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
typedef struct PSH_GlobalsRec_* PSH_Globals;
typedef FT_Error
(*PSH_Globals_NewFunc)( FT_Memory memory,
T1_Private* private_dict,
PSH_Globals* aglobals );
typedef FT_Error
(*PSH_Globals_SetScaleFunc)( PSH_Globals globals,
FT_Fixed x_scale,
FT_Fixed y_scale,
FT_Fixed x_delta,
FT_Fixed y_delta );
typedef void
(*PSH_Globals_DestroyFunc)( PSH_Globals globals );
typedef struct PSH_Globals_FuncsRec_
{
PSH_Globals_NewFunc create;
PSH_Globals_SetScaleFunc set_scale;
PSH_Globals_DestroyFunc destroy;
} PSH_Globals_FuncsRec, *PSH_Globals_Funcs;
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** PUBLIC TYPE 1 HINTS RECORDER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************
*
* @type:
* T1_Hints
*
* @description:
* This is a handle to an opaque structure used to record glyph hints
* from a Type 1 character glyph character string.
*
* The methods used to operate on this object are defined by the
* @T1_Hints_FuncsRec structure. Recording glyph hints is normally
* achieved through the following scheme:
*
* - Open a new hint recording session by calling the `open' method.
* This rewinds the recorder and prepare it for new input.
*
* - For each hint found in the glyph charstring, call the corresponding
* method (`stem', `stem3', or `reset'). Note that these functions do
* not return an error code.
*
* - Close the recording session by calling the `close' method. It
* returns an error code if the hints were invalid or something
* strange happened (e.g., memory shortage).
*
* The hints accumulated in the object can later be used by the
* PostScript hinter.
*
*/
typedef struct T1_HintsRec_* T1_Hints;
/*************************************************************************
*
* @type:
* T1_Hints_Funcs
*
* @description:
* A pointer to the @T1_Hints_FuncsRec structure that defines the API of
* a given @T1_Hints object.
*
*/
typedef const struct T1_Hints_FuncsRec_* T1_Hints_Funcs;
/*************************************************************************
*
* @functype:
* T1_Hints_OpenFunc
*
* @description:
* A method of the @T1_Hints class used to prepare it for a new Type 1
* hints recording session.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* @note:
* You should always call the @T1_Hints_CloseFunc method in order to
* close an opened recording session.
*
*/
typedef void
(*T1_Hints_OpenFunc)( T1_Hints hints );
/*************************************************************************
*
* @functype:
* T1_Hints_SetStemFunc
*
* @description:
* A method of the @T1_Hints class used to record a new horizontal or
* vertical stem. This corresponds to the Type 1 `hstem' and `vstem'
* operators.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* dimension ::
* 0 for horizontal stems (hstem), 1 for vertical ones (vstem).
*
* coords ::
* Array of 2 integers, used as (position,length) stem descriptor.
*
* @note:
* Use vertical coordinates (y) for horizontal stems (dim=0). Use
* horizontal coordinates (x) for vertical stems (dim=1).
*
* `coords[0]' is the absolute stem position (lowest coordinate);
* `coords[1]' is the length.
*
* The length can be negative, in which case it must be either -20 or
* -21. It is interpreted as a `ghost' stem, according to the Type 1
* specification.
*
* If the length is -21 (corresponding to a bottom ghost stem), then
* the real stem position is `coords[0]+coords[1]'.
*
*/
typedef void
(*T1_Hints_SetStemFunc)( T1_Hints hints,
FT_UInt dimension,
FT_Long* coords );
/*************************************************************************
*
* @functype:
* T1_Hints_SetStem3Func
*
* @description:
* A method of the @T1_Hints class used to record three
* counter-controlled horizontal or vertical stems at once.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* dimension ::
* 0 for horizontal stems, 1 for vertical ones.
*
* coords ::
* An array of 6 integers, holding 3 (position,length) pairs for the
* counter-controlled stems.
*
* @note:
* Use vertical coordinates (y) for horizontal stems (dim=0). Use
* horizontal coordinates (x) for vertical stems (dim=1).
*
* The lengths cannot be negative (ghost stems are never
* counter-controlled).
*
*/
typedef void
(*T1_Hints_SetStem3Func)( T1_Hints hints,
FT_UInt dimension,
FT_Long* coords );
/*************************************************************************
*
* @functype:
* T1_Hints_ResetFunc
*
* @description:
* A method of the @T1_Hints class used to reset the stems hints in a
* recording session.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* end_point ::
* The index of the last point in the input glyph in which the
* previously defined hints apply.
*
*/
typedef void
(*T1_Hints_ResetFunc)( T1_Hints hints,
FT_UInt end_point );
/*************************************************************************
*
* @functype:
* T1_Hints_CloseFunc
*
* @description:
* A method of the @T1_Hints class used to close a hint recording
* session.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* end_point ::
* The index of the last point in the input glyph.
*
* @return:
* FreeType error code. 0 means success.
*
* @note:
* The error code is set to indicate that an error occurred during the
* recording session.
*
*/
typedef FT_Error
(*T1_Hints_CloseFunc)( T1_Hints hints,
FT_UInt end_point );
/*************************************************************************
*
* @functype:
* T1_Hints_ApplyFunc
*
* @description:
* A method of the @T1_Hints class used to apply hints to the
* corresponding glyph outline. Must be called once all hints have been
* recorded.
*
* @input:
* hints ::
* A handle to the Type 1 hints recorder.
*
* outline ::
* A pointer to the target outline descriptor.
*
* globals ::
* The hinter globals for this font.
*
* hint_mode ::
* Hinting information.
*
* @return:
* FreeType error code. 0 means success.
*
* @note:
* On input, all points within the outline are in font coordinates. On
* output, they are in 1/64th of pixels.
*
* The scaling transformation is taken from the `globals' object which
* must correspond to the same font as the glyph.
*
*/
typedef FT_Error
(*T1_Hints_ApplyFunc)( T1_Hints hints,
FT_Outline* outline,
PSH_Globals globals,
FT_Render_Mode hint_mode );
/*************************************************************************
*
* @struct:
* T1_Hints_FuncsRec
*
* @description:
* The structure used to provide the API to @T1_Hints objects.
*
* @fields:
* hints ::
* A handle to the T1 Hints recorder.
*
* open ::
* The function to open a recording session.
*
* close ::
* The function to close a recording session.
*
* stem ::
* The function to set a simple stem.
*
* stem3 ::
* The function to set counter-controlled stems.
*
* reset ::
* The function to reset stem hints.
*
* apply ::
* The function to apply the hints to the corresponding glyph outline.
*
*/
typedef struct T1_Hints_FuncsRec_
{
T1_Hints hints;
T1_Hints_OpenFunc open;
T1_Hints_CloseFunc close;
T1_Hints_SetStemFunc stem;
T1_Hints_SetStem3Func stem3;
T1_Hints_ResetFunc reset;
T1_Hints_ApplyFunc apply;
} T1_Hints_FuncsRec;
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** PUBLIC TYPE 2 HINTS RECORDER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************
*
* @type:
* T2_Hints
*
* @description:
* This is a handle to an opaque structure used to record glyph hints
* from a Type 2 character glyph character string.
*
* The methods used to operate on this object are defined by the
* @T2_Hints_FuncsRec structure. Recording glyph hints is normally
* achieved through the following scheme:
*
* - Open a new hint recording session by calling the `open' method.
* This rewinds the recorder and prepare it for new input.
*
* - For each hint found in the glyph charstring, call the corresponding
* method (`stems', `hintmask', `counters'). Note that these
* functions do not return an error code.
*
* - Close the recording session by calling the `close' method. It
* returns an error code if the hints were invalid or something
* strange happened (e.g., memory shortage).
*
* The hints accumulated in the object can later be used by the
* Postscript hinter.
*
*/
typedef struct T2_HintsRec_* T2_Hints;
/*************************************************************************
*
* @type:
* T2_Hints_Funcs
*
* @description:
* A pointer to the @T2_Hints_FuncsRec structure that defines the API of
* a given @T2_Hints object.
*
*/
typedef const struct T2_Hints_FuncsRec_* T2_Hints_Funcs;
/*************************************************************************
*
* @functype:
* T2_Hints_OpenFunc
*
* @description:
* A method of the @T2_Hints class used to prepare it for a new Type 2
* hints recording session.
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* @note:
* You should always call the @T2_Hints_CloseFunc method in order to
* close an opened recording session.
*
*/
typedef void
(*T2_Hints_OpenFunc)( T2_Hints hints );
/*************************************************************************
*
* @functype:
* T2_Hints_StemsFunc
*
* @description:
* A method of the @T2_Hints class used to set the table of stems in
* either the vertical or horizontal dimension. Equivalent to the
* `hstem', `vstem', `hstemhm', and `vstemhm' Type 2 operators.
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* dimension ::
* 0 for horizontal stems (hstem), 1 for vertical ones (vstem).
*
* count ::
* The number of stems.
*
* coords ::
* An array of `count' (position,length) pairs.
*
* @note:
* Use vertical coordinates (y) for horizontal stems (dim=0). Use
* horizontal coordinates (x) for vertical stems (dim=1).
*
* There are `2*count' elements in the `coords' aray. Each even element
* is an absolute position in font units, each odd element is a length
* in font units.
*
* A length can be negative, in which case it must be either -20 or
* -21. It is interpreted as a `ghost' stem, according to the Type 1
* specification.
*
*/
typedef void
(*T2_Hints_StemsFunc)( T2_Hints hints,
FT_UInt dimension,
FT_UInt count,
FT_Fixed* coordinates );
/*************************************************************************
*
* @functype:
* T2_Hints_MaskFunc
*
* @description:
* A method of the @T2_Hints class used to set a given hintmask (this
* corresponds to the `hintmask' Type 2 operator).
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* end_point ::
* The glyph index of the last point to which the previously defined
* or activated hints apply.
*
* bit_count ::
* The number of bits in the hint mask.
*
* bytes ::
* An array of bytes modelling the hint mask.
*
* @note:
* If the hintmask starts the charstring (before any glyph point
* definition), the value of `end_point' should be 0.
*
* `bit_count' is the number of meaningful bits in the `bytes' array; it
* must be equal to the total number of hints defined so far (i.e.,
* horizontal+verticals).
*
* The `bytes' array can come directly from the Type 2 charstring and
* respects the same format.
*
*/
typedef void
(*T2_Hints_MaskFunc)( T2_Hints hints,
FT_UInt end_point,
FT_UInt bit_count,
const FT_Byte* bytes );
/*************************************************************************
*
* @functype:
* T2_Hints_CounterFunc
*
* @description:
* A method of the @T2_Hints class used to set a given counter mask
* (this corresponds to the `hintmask' Type 2 operator).
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* end_point ::
* A glyph index of the last point to which the previously defined or
* active hints apply.
*
* bit_count ::
* The number of bits in the hint mask.
*
* bytes ::
* An array of bytes modelling the hint mask.
*
* @note:
* If the hintmask starts the charstring (before any glyph point
* definition), the value of `end_point' should be 0.
*
* `bit_count' is the number of meaningful bits in the `bytes' array; it
* must be equal to the total number of hints defined so far (i.e.,
* horizontal+verticals).
*
* The `bytes' array can come directly from the Type 2 charstring and
* respects the same format.
*
*/
typedef void
(*T2_Hints_CounterFunc)( T2_Hints hints,
FT_UInt bit_count,
const FT_Byte* bytes );
/*************************************************************************
*
* @functype:
* T2_Hints_CloseFunc
*
* @description:
* A method of the @T2_Hints class used to close a hint recording
* session.
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* end_point ::
* The index of the last point in the input glyph.
*
* @return:
* FreeType error code. 0 means success.
*
* @note:
* The error code is set to indicate that an error occurred during the
* recording session.
*
*/
typedef FT_Error
(*T2_Hints_CloseFunc)( T2_Hints hints,
FT_UInt end_point );
/*************************************************************************
*
* @functype:
* T2_Hints_ApplyFunc
*
* @description:
* A method of the @T2_Hints class used to apply hints to the
* corresponding glyph outline. Must be called after the `close'
* method.
*
* @input:
* hints ::
* A handle to the Type 2 hints recorder.
*
* outline ::
* A pointer to the target outline descriptor.
*
* globals ::
* The hinter globals for this font.
*
* hint_mode ::
* Hinting information.
*
* @return:
* FreeType error code. 0 means success.
*
* @note:
* On input, all points within the outline are in font coordinates. On
* output, they are in 1/64th of pixels.
*
* The scaling transformation is taken from the `globals' object which
* must correspond to the same font than the glyph.
*
*/
typedef FT_Error
(*T2_Hints_ApplyFunc)( T2_Hints hints,
FT_Outline* outline,
PSH_Globals globals,
FT_Render_Mode hint_mode );
/*************************************************************************
*
* @struct:
* T2_Hints_FuncsRec
*
* @description:
* The structure used to provide the API to @T2_Hints objects.
*
* @fields:
* hints ::
* A handle to the T2 hints recorder object.
*
* open ::
* The function to open a recording session.
*
* close ::
* The function to close a recording session.
*
* stems ::
* The function to set the dimension's stems table.
*
* hintmask ::
* The function to set hint masks.
*
* counter ::
* The function to set counter masks.
*
* apply ::
* The function to apply the hints on the corresponding glyph outline.
*
*/
typedef struct T2_Hints_FuncsRec_
{
T2_Hints hints;
T2_Hints_OpenFunc open;
T2_Hints_CloseFunc close;
T2_Hints_StemsFunc stems;
T2_Hints_MaskFunc hintmask;
T2_Hints_CounterFunc counter;
T2_Hints_ApplyFunc apply;
} T2_Hints_FuncsRec;
/* */
typedef struct PSHinter_Interface_
{
PSH_Globals_Funcs (*get_globals_funcs)( FT_Module module );
T1_Hints_Funcs (*get_t1_funcs) ( FT_Module module );
T2_Hints_Funcs (*get_t2_funcs) ( FT_Module module );
} PSHinter_Interface;
typedef PSHinter_Interface* PSHinter_Service;
FT_END_HEADER
#endif /* __PSHINTS_H__ */
/* END */
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