/* Copyright (C) 1994, 1996, 1997, 1998, 1999 Aladdin Enterprises.  All rights reserved.
  
  This file is part of GNU Ghostscript.
  
  GNU Ghostscript is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility
  to anyone for the consequences of using it or for whether it serves any
  particular purpose or works at all, unless he says so in writing.  Refer
  to the GNU General Public License for full details.
  
  Everyone is granted permission to copy, modify and redistribute GNU
  Ghostscript, but only under the conditions described in the GNU General
  Public License.  A copy of this license is supposed to have been given
  to you along with GNU Ghostscript so you can know your rights and
  responsibilities.  It should be in a file named COPYING.  Among other
  things, the copyright notice and this notice must be preserved on all
  copies.
*/

/*$RCSfile: gzcpath.h,v $ $Revision: 1.2.2.1 $ */
/* Structure definitions for clipping paths */
/* Requires gzpath.h. */

#ifndef gzcpath_INCLUDED
#  define gzcpath_INCLUDED

#include "gxcpath.h"

/*
 * The reference counting considerations for clip paths are the same as
 * for paths.  We need a separate reference count for the clip list,
 * since its existence and lifetime are not necessarily the same as
 * those of the path.
 */

typedef struct gx_clip_rect_list_s {
    rc_header rc;
    gx_clip_list list;
} gx_clip_rect_list;

#define private_st_clip_rect_list()	/* in gxcpath.c */\
  gs_private_st_ptrs_add0(st_clip_rect_list, gx_clip_rect_list,\
    "gx_clip_rect_list", clip_rect_list_enum_ptrs, clip_rect_list_reloc_ptrs,\
    st_clip_list, list)

/* gx_clip_path is a 'subclass' of gx_path. */
struct gx_clip_path_s {
    gx_path path;
    gx_clip_rect_list local_list;
    int rule;			/* rule for insideness of path */
    /* Anything within the inner_box is guaranteed to fall */
    /* entirely within the clipping path. */
    gs_fixed_rect inner_box;
    /* Anything outside the outer_box is guaranteed to fall */
    /* entirely outside the clipping path.  This is the same */
    /* as the path bounding box, widened to pixel boundaries. */
    gs_fixed_rect outer_box;
    gx_clip_rect_list *rect_list;
    bool path_valid;		/* path representation is valid */
    /* The id changes whenever the clipping region changes. */
    gs_id id;
};

extern_st(st_clip_path);
#define public_st_clip_path()	/* in gxcpath.c */\
  gs_public_st_composite(st_clip_path, gx_clip_path, "clip_path",\
    clip_path_enum_ptrs, clip_path_reloc_ptrs)
#define st_clip_path_max_ptrs (st_path_max_ptrs + 1)

/* Inline accessors. */
#define gx_cpath_is_shared(pcpath)\
  ((pcpath)->rect_list->rc.ref_count > 1)

/* Define the structure for enumerating a clipping list. */
typedef enum {
    visit_left = 1,
    visit_right = 2
} cpe_visit_t;
typedef enum {
    cpe_scan, cpe_left, cpe_right, cpe_close, cpe_done
} cpe_state_t;
struct gs_cpath_enum_s {
    gs_path_enum path_enum;	/* used iff clipping path exists as a path, */
    /* must be first for subclassing */
    bool using_path;
    gx_clip_rect *visit;	/* scan pointer for finding next start */
    gx_clip_rect *rp;		/* scan pointer for current rectangle */
    cpe_visit_t first_visit;
    cpe_state_t state;
    bool have_line;
    gs_int_point line_end;
    bool any_rectangles;
};

#define private_st_cpath_enum()		/* in gxcpath.c */\
  gs_private_st_suffix_add2(st_cpath_enum, gs_cpath_enum, "gs_cpath_enum",\
    cpath_enum_enum_ptrs, cpath_enum_reloc_ptrs, st_path_enum,\
    visit, rp)

#endif /* gzcpath_INCLUDED */
