/* Copyright (C) 2001-2006 Artifex Software, Inc.
   All Rights Reserved.
  
   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied, modified
   or distributed except as expressly authorized under the terms of that
   license.  Refer to licensing information at http://www.artifex.com/
   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
*/

/* $Id: gxband.h 8022 2007-06-05 22:23:38Z giles $ */
/* Band-processing parameters for Ghostscript */

#ifndef gxband_INCLUDED
#  define gxband_INCLUDED

#include "gxclio.h"

/*
 * Define the parameters controlling banding.
 */
typedef struct gx_band_params_s {
    bool page_uses_transparency; /* PDF 1.4 transparency is used on the page */
    int BandWidth;		/* (optional) band width in pixels */
    int BandHeight;		/* (optional) */
    long BandBufferSpace;	/* (optional) */
} gx_band_params_t;

#define BAND_PARAMS_INITIAL_VALUES 0, 0, 0

/*
 * Define information about the colors used on a page.
 */
typedef struct gx_colors_used_s {
    gx_color_index or;		/* the "or" of all the used colors */
    bool slow_rop;		/* true if any RasterOps that can't be */
				/* executed plane-by-plane on CMYK devices */
} gx_colors_used_t;

/*
 * We want to store color usage information for each band in the page_info
 * structure, but we also want this structure to be of a fixed (and
 * reasonable) size.  We do this by allocating a fixed number of colors_used
 * structures in the page_info structure, and if there are more bands than
 * we have allocated, we simply reduce the precision of the information by
 * letting each colors_used structure cover multiple bands.
 *
 * 30 entries would be large enough to cover A4 paper (11.3") at 600 dpi
 * with 256-scan-line bands.  We pick 50 somewhat arbitrarily.
 */
#define PAGE_INFO_NUM_COLORS_USED 50

/*
 * Define the information for a saved page.
 */
typedef struct gx_band_page_info_s {
    char cfname[gp_file_name_sizeof];	/* command file name */
    clist_file_ptr cfile;	/* command file, normally 0 */
    char bfname[gp_file_name_sizeof];	/* block file name */
    clist_file_ptr bfile;	/* block file, normally 0 */
    const clist_io_procs_t *io_procs;
    uint tile_cache_size;	/* size of tile cache */
    int64_t bfile_end_pos;		/* ftell at end of bfile */
    gx_band_params_t band_params;  /* parameters used when writing band list */
				/* (actual values, no 0s) */
    int scan_lines_per_colors_used; /* number of scan lines per colors_used */
				/* entry (a multiple of the band height) */
    gx_colors_used_t band_colors_used[PAGE_INFO_NUM_COLORS_USED];  /* colors used on the page */
} gx_band_page_info_t;
#define PAGE_INFO_NULL_VALUES\
  { 0 }, 0, { 0 }, NULL, 0, 0, 0, { BAND_PARAMS_INITIAL_VALUES },\
  0x3fffffff, { { 0 } }

/*
 * By convention, the structure member containing the above is called
 * page_info.  Define shorthand accessors for its members.
 */
#define page_cfile page_info.cfile
#define page_cfname page_info.cfname
#define page_bfile page_info.bfile
#define page_bfname page_info.bfname
#define page_tile_cache_size page_info.tile_cache_size
#define page_bfile_end_pos page_info.bfile_end_pos
#define page_band_height page_info.band_params.BandHeight

#endif /* ndef gxband_INCLUDED */
