/*******************************************************************
*
* t1gload.h 1.0
*
* Type1 Glyph Loader.
*
* Copyright 1996-1998 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 Type 1 glyph loader uses three distinct objects to build
* scaled and hinted outlines from a charstrings program. These are :
*
* - a glyph builder, T1_Builder, used to store the built outline
*
* - a glyph hinter, T1_Hinter, used to record and apply the stem
* hints
*
* - a charstrings interpreter, T1_Decoder, used to parse the
* Type 1 charstrings stream, manage a stack and call the builder
* and/or hinter depending on the opcodes.
*
* Ideally, a Type 2 glyph loader would only need to have its own
* T2_Decoder object (assuming the hinter is able to manage all
* kinds of hints).
*
******************************************************************/
#ifndef T1GLOAD_H
#define T1GLOAD_H
#include <t1objs.h>
#ifdef __cplusplus
extern "C" {
#endif
/*************************************************************************/
/* */
/* <Structure> T1_Builder_Funcs */
/* */
/* <Description> */
/* a structure used to store the address of various functions */
/* used by a glyph builder to implement the outline's "path */
/* construction". */
/* */
/* */
typedef struct T1_Builder_ T1_Builder;
typedef T1_Error (*T1_Builder_EndChar)( T1_Builder* loader );
typedef T1_Error (*T1_Builder_Sbw) ( T1_Builder* loader,
T1_Pos sbx,
T1_Pos sby,
T1_Pos wx,
T1_Pos wy );
typedef T1_Error (*T1_Builder_ClosePath)( T1_Builder* loader );
typedef T1_Error (*T1_Builder_RLineTo)( T1_Builder* loader,
T1_Pos dx,
T1_Pos dy );
typedef T1_Error (*T1_Builder_RMoveTo)( T1_Builder* loader,
T1_Pos dx,
T1_Pos dy );
typedef T1_Error (*T1_Builder_RCurveTo)( T1_Builder* loader,
T1_Pos dx1,
T1_Pos dy1,
T1_Pos dx2,
T1_Pos dy2,
T1_Pos dx3,
T1_Pos dy3 );
typedef struct T1_Builder_Funcs_
{
T1_Builder_EndChar end_char;
T1_Builder_Sbw set_bearing_point;
T1_Builder_ClosePath close_path;
T1_Builder_RLineTo rline_to;
T1_Builder_RMoveTo rmove_to;
T1_Builder_RCurveTo rcurve_to;
} T1_Builder_Funcs;
/*************************************************************************/
/* */
/* <Structure> T1_Builder */
/* */
/* <Description> */
/* a structure used during glyph loading to store its outline. */
/* */
/* <Fields> */
/* system :: current system object */
/* face :: current face object */
/* size :: current size object */
/* glyph :: current glyph slot */
/* */
/* current :: current glyph outline */
/* base :: base glyph outline */
/* */
/* max_points :: maximum points in builder outline */
/* max_contours :: maximum contours in builder outline */
/* */
/* last :: last point position */
/* */
/* scale_x :: horizontal scale ( FUnits to sub-pixels ) */
/* scale_y :: vertical scale ( FUnits to sub-pixels ) */
/* pos_x :: horizontal translation (composite glyphs) */
/* pos_y :: vertical translation (composite glyph) */
/* */
/* left_bearing :: left side bearing point */
/* advance :: horizontal advance vector */
/* */
/* path_begun :: flag, indicates that a new path has begun */
/* load_points :: flag, if not set, no points are loaded */
/* */
/* pass :: pass number for multi-pass hinters */
/* */
/* funcs :: table of builder functions used to perform */
/* the outline's path construction */
/* */
/* hint_point :: index of next point to hint.. */
/* */
/* */
/* */
/* */
struct T1_Builder_
{
FT_Memory memory;
T1_Face face;
T1_Size size;
T1_GlyphSlot glyph;
FT_Outline current; /* the current glyph outline */
FT_Outline base; /* the composite glyph outline */
T1_Int max_points; /* capacity of base outline in points */
T1_Int max_contours; /* capacity of base outline in contours */
T1_Vector last;
T1_Fixed scale_x;
T1_Fixed scale_y;
T1_Pos pos_x;
T1_Pos pos_y;
T1_Vector left_bearing;
T1_Vector advance;
T1_BBox bbox; /* bounding box */
T1_Bool path_begun;
T1_Bool load_points;
T1_Int pass;
T1_Int hint_point;
/* path construction function interface */
T1_Builder_Funcs funcs;
};
/*************************************************************************/
/* */
/* <Structure> T1_Hinter_Funcs */
/* */
/* <Description> */
/* a structure used to store the address of various functions */
/* used by a Type 1 hinter to perform outline hinting. */
/* */
typedef T1_Error (*T1_Hinter_ChangeHints)( T1_Builder* builder );
typedef T1_Error (*T1_Hinter_DotSection)( T1_Builder* builder );
typedef T1_Error (*T1_Hinter_Stem)( T1_Builder* builder,
T1_Pos pos,
T1_Pos width,
T1_Bool vertical );
typedef T1_Error (*T1_Hinter_Stem3)( T1_Builder* builder,
T1_Pos pos0,
T1_Pos width0,
T1_Pos pos1,
T1_Pos width1,
T1_Pos pos2,
T1_Pos width2,
T1_Bool vertical );
typedef struct T1_Hinter_Func_
{
T1_Hinter_ChangeHints change_hints;
T1_Hinter_DotSection dot_section;
T1_Hinter_Stem stem;
T1_Hinter_Stem3 stem3;
} T1_Hinter_Funcs;
typedef enum T1_Operator_
{
op_none = 0,
op_endchar,
op_hsbw,
op_seac,
op_sbw,
op_closepath,
op_hlineto,
op_hmoveto,
op_hvcurveto,
op_rlineto,
op_rmoveto,
op_rrcurveto,
op_vhcurveto,
op_vlineto,
op_vmoveto,
op_dotsection,
op_hstem,
op_hstem3,
op_vstem,
op_vstem3,
op_div,
op_callothersubr,
op_callsubr,
op_pop,
op_return,
op_setcurrentpoint,
op_max /* never remove this one */
} T1_Operator;
/* execution context charstring zone */
typedef struct T1_Decoder_Zone_
{
T1_Byte* base;
T1_Byte* limit;
T1_Byte* cursor;
} T1_Decoder_Zone;
typedef struct T1_Decoder_
{
T1_Builder builder;
T1_Hinter_Funcs hinter;
T1_Int stack[ T1_MAX_CHARSTRINGS_OPERANDS ];
T1_Int* top;
T1_Decoder_Zone zones[ T1_MAX_SUBRS_CALLS+1 ];
T1_Decoder_Zone* zone;
T1_Int flex_state;
T1_Int num_flex_vectors;
T1_Vector flex_vectors[7];
} T1_Decoder;
/*********************************************************************
*
* <Function>
* T1_Init_Builder
*
* <Description>
* Initialise a given glyph builder.
*
* <Input>
* builder :: glyph builder to initialise
* face :: current face object
* size :: current size object
* glyph :: current glyph object
* funcs :: glyph builder functions (or "methods").
*
* <Note>
* This function is exported for now because it is used by the
* "t1dump" utility. Later, it will be accessed through a
* format-specific extension
*
*********************************************************************/
EXPORT_DEF
void T1_Init_Builder( T1_Builder* builder,
T1_Face face,
T1_Size size,
T1_GlyphSlot glyph,
const T1_Builder_Funcs* funcs );
/*********************************************************************
*
* <Function>
* T1_Done_Builder
*
* <Description>
* Finalise a given glyph builder. Its content can still be
* used after the call, but the function saves important information
* within the corresponding glyph slot.
*
* <Input>
* builder :: glyph builder to initialise
*
* <Note>
* This function is exported for now because it is used by the
* "t1dump" utility. Later, it will be accessed through a
* format-specific extension
*
*********************************************************************/
EXPORT_DEF
void T1_Done_Builder( T1_Builder* builder );
/*********************************************************************
*
* <Function>
* T1_Init_Decoder
*
* <Description>
* Initialise a given Type 1 decoder for parsing
*
* <Input>
* decoder :: Type 1 decoder to initialise
* funcs :: hinter functions interface
*
* <Note>
* This function is exported for now because it is used by the
* "t1dump" utility. Later, it will be accessed through a
* format-specific extension
*
*********************************************************************/
EXPORT_DEF
void T1_Init_Decoder( T1_Decoder* decoder,
const T1_Hinter_Funcs* funcs );
/* Compute the maximum advance width of a font through quick parsing */
LOCAL_DEF
T1_Error T1_Compute_Max_Advance( T1_Face face,
T1_Int *max_advance );
/* This function is exported, because it is used by the T1Dump utility */
EXPORT_DEF
T1_Error T1_Parse_CharStrings( T1_Decoder* decoder,
T1_Byte* charstring_base,
T1_Int charstring_len,
T1_Int num_subrs,
T1_Byte** subrs_base,
T1_Int* subrs_len );
/*************************************************************************/
/* */
/* <Function> T1_Add_Points */
/* */
/* <Description> */
/* Checks that there is enough room in the current load glyph outline */
/* to accept "num_points" additional outline points. If not, this */
/* function grows the load outline's arrays accordingly.. */
/* */
/* <Input> */
/* builder :: pointer to glyph builder object */
/* num_points :: number of points that will be added later */
/* */
/* <Return> */
/* Type1 error code. 0 means success */
/* */
/* <Note> */
/* This function does NOT update the points count in the glyph loader */
/* This must be done by the caller itself, after this function is */
/* invoked.. */
/* */
LOCAL_DEF
T1_Error T1_Add_Points( T1_Builder* builder,
T1_Int num_points );
/*************************************************************************/
/* */
/* <Function> T1_Add_Contours */
/* */
/* <Description> */
/* Checks that there is enough room in the current load glyph outline */
/* to accept "num_contours" additional contours. If not, this func */
/* the load outline's arrays accordingly.. */
/* */
/* <Input> */
/* builder :: pointer to glyph builder object */
/* num_contours :: number of contours that will be added later */
/* */
/* <Return> */
/* Type1 error code. 0 means success */
/* */
/* <Note> */
/* This function does NOT update the contours count in the load glyph */
/* This must be done by the caller itself, after this function is */
/* invoked.. */
/* */
LOCAL_DEF
T1_Error T1_Add_Contours( T1_Builder* builder,
T1_Int num_contours );
LOCAL_DEF
T1_Error T1_Load_Glyph( T1_GlyphSlot glyph,
T1_Size size,
T1_Int glyph_index,
T1_Int load_flags );
#ifdef __cplusplus
}
#endif
#endif /* T1GLOAD_H */
