freetype2/src/type1z/t1gload.h

189 lines
6.8 KiB
C

/*******************************************************************
*
* 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 */
/* */
/* <Description> */
/* a structure used during glyph loading to store its outline. */
/* */
/* <Fields> */
/* system :: current system object */
/* face :: current face 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 */
/* */
/* error :: an error code that is only used to report */
/* memory allocation problems.. */
/* */
/* metrics_only :: a boolean indicating that we only want to */
/* compute the metrics of a given glyph, not load */
/* all of its points.. */
/* */
typedef struct T1_Builder_
{
FT_Memory memory;
T1_Face face;
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_Bool no_recurse;
T1_Error error; /* only used for memory errors */
T1_Bool metrics_only;
} T1_Builder;
/* 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_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;
LOCAL_DEF
void T1_Init_Builder( T1_Builder* builder,
T1_Face face,
T1_Size size,
T1_GlyphSlot glyph );
LOCAL_DEF
void T1_Done_Builder( T1_Builder* builder );
LOCAL_DEF
void T1_Init_Decoder( T1_Decoder* decoder );
/* 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 */
LOCAL_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 );
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 */