/* pxl-outline.h: find a list of outlines which make up one character.

Copyright (C) 1992 Free Software Foundation, Inc.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#ifndef PXL_OUTLINE_H
#define PXL_OUTLINE_H

#include "types.h"


/* This is a list of contiguous points on the bitmap.  */
typedef struct
{
  coordinate_type *data;
  unsigned length;
  boolean clockwise;
} pixel_outline_type;

/* The Nth coordinate in the list.  */
#define O_COORDINATE(p_o, n) ((p_o).data[n])

/* The length of the list.  */
#define O_LENGTH(p_o) ((p_o).length)

/* Whether the outline moves clockwise or counterclockwise.  */
#define O_CLOCKWISE(p_o) ((p_o).clockwise)

/* Since a pixel outline is cyclic, the index of thenext coordinate
   after the last is the first, and the previous coordinate before the
   first is the last.  */
#define O_NEXT(p_o, n) (((n) + 1) % O_LENGTH (p_o))
#define O_PREV(p_o, n) ((n) == 0				\
                         ? O_LENGTH (p_o) - 1			\
                         : (n) - 1)
   
/* And the character turns into a list of such lists.  */
typedef struct
{
  pixel_outline_type *data;
  unsigned length;
} pixel_outline_list_type;

/* The Nth list in the list of lists.  */
#define O_LIST_OUTLINE(p_o_l, n) ((p_o_l).data[n])

/* The length of the list of lists.  */
#define O_LIST_LENGTH(p_o_l) ((p_o_l).length)


/* Find all pixels on the outline in the character C.  */
extern pixel_outline_list_type find_outline_pixels ();

/* Free the memory in the list.  */
extern void free_pixel_outline_list (pixel_outline_list_type *);

#endif /* not PXL_OUTLINE_H */