kicad/potrace/potracelib.h

146 lines
4.7 KiB
C

/* Copyright (C) 2001-2017 Peter Selinger.
* This file is part of Potrace. It is free software and it is covered
* by the GNU General Public License. See the file COPYING for details. */
#ifndef POTRACELIB_H
#define POTRACELIB_H
/* this file defines the API for the core Potrace library. For a more
* detailed description of the API, see potracelib.pdf */
#ifdef __cplusplus
extern "C" {
#endif
/* ---------------------------------------------------------------------- */
/* tracing parameters */
/* turn policies */
#define POTRACE_TURNPOLICY_BLACK 0
#define POTRACE_TURNPOLICY_WHITE 1
#define POTRACE_TURNPOLICY_LEFT 2
#define POTRACE_TURNPOLICY_RIGHT 3
#define POTRACE_TURNPOLICY_MINORITY 4
#define POTRACE_TURNPOLICY_MAJORITY 5
#define POTRACE_TURNPOLICY_RANDOM 6
/* structure to hold progress bar callback data */
struct potrace_progress_s
{
void ( * callback )( double progress, void* privdata ); /* callback fn */
void* data; /* callback function's private data */
double min, max; /* desired range of progress, e.g. 0.0 to 1.0 */
double epsilon; /* granularity: can skip smaller increments */
};
typedef struct potrace_progress_s potrace_progress_t;
/* structure to hold tracing parameters */
struct potrace_param_s
{
int turdsize; /* area of largest path to be ignored */
int turnpolicy; /* resolves ambiguous turns in path decomposition */
double alphamax; /* corner threshold */
int opticurve; /* use curve optimization? */
double opttolerance; /* curve optimization tolerance */
potrace_progress_t progress; /* progress callback function */
};
typedef struct potrace_param_s potrace_param_t;
/* ---------------------------------------------------------------------- */
/* bitmaps */
/* native word size */
typedef unsigned long potrace_word;
/* Internal bitmap format. The n-th scanline starts at scanline(n) =
* (map + n*dy). Raster data is stored as a sequence of potrace_words
* (NOT bytes). The leftmost bit of scanline n is the most significant
* bit of scanline(n)[0]. */
struct potrace_bitmap_s
{
int w, h; /* width and height, in pixels */
int dy; /* words per scanline (not bytes) */
potrace_word* map; /* raw data, dy*h words */
};
typedef struct potrace_bitmap_s potrace_bitmap_t;
/* ---------------------------------------------------------------------- */
/* curves */
/* point */
struct potrace_dpoint_s
{
double x, y;
};
typedef struct potrace_dpoint_s potrace_dpoint_t;
/* segment tags */
#define POTRACE_CURVETO 1
#define POTRACE_CORNER 2
/* closed curve segment */
struct potrace_curve_s
{
int n; /* number of segments */
int* tag; /* tag[n]: POTRACE_CURVETO or POTRACE_CORNER */
potrace_dpoint_t( *c )[3]; /* c[n][3]: control points.
* c[n][0] is unused for tag[n]=POTRACE_CORNER */
};
typedef struct potrace_curve_s potrace_curve_t;
/* Linked list of signed curve segments. Also carries a tree structure. */
struct potrace_path_s
{
int area; /* area of the bitmap path */
int sign; /* '+' or '-', depending on orientation */
potrace_curve_t curve; /* this path's vector data */
struct potrace_path_s* next; /* linked list structure */
struct potrace_path_s* childlist; /* tree structure */
struct potrace_path_s* sibling; /* tree structure */
struct potrace_privpath_s* priv; /* private state */
};
typedef struct potrace_path_s potrace_path_t;
/* ---------------------------------------------------------------------- */
/* Potrace state */
#define POTRACE_STATUS_OK 0
#define POTRACE_STATUS_INCOMPLETE 1
struct potrace_state_s
{
int status;
potrace_path_t* plist; /* vector data */
struct potrace_privstate_s* priv; /* private state */
};
typedef struct potrace_state_s potrace_state_t;
/* ---------------------------------------------------------------------- */
/* API functions */
/* get default parameters */
potrace_param_t* potrace_param_default( void );
/* free parameter set */
void potrace_param_free( potrace_param_t* p );
/* trace a bitmap */
potrace_state_t* potrace_trace( const potrace_param_t* param, const potrace_bitmap_t* bm );
/* free a Potrace state */
void potrace_state_free( potrace_state_t* st );
/* return a static plain text version string identifying this version
* of potracelib */
const char* potrace_version( void );
#ifdef __cplusplus
} /* end of extern "C" */
#endif
#endif /* POTRACELIB_H */