/* Copyright (C) 1994, 1995, 1996, 1997, 1998 Aladdin Enterprises.  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 the license contained in the file LICENSE in this distribution.
  
  For more information about licensing, please refer to
  http://www.ghostscript.com/licensing/. For information on
  commercial licensing, go to http://www.artifex.com/licensing/ or
  contact Artifex Software, Inc., 101 Lucas Valley Road #110,
  San Rafael, CA  94903, U.S.A., +1(415)492-9861.
*/

/*$Id: gxdither.h,v 1.2.6.1 2002/02/22 19:45:58 ray Exp $ */
/* Interface to gxdither.c */

#ifndef gxdither_INCLUDED
#  define gxdither_INCLUDED

#include "gxfrac.h"

#ifndef gx_device_halftone_DEFINED
#  define gx_device_halftone_DEFINED
typedef struct gx_device_halftone_s gx_device_halftone;
#endif

/*
 * Note that in the procedures below, the colors are specified by fracs,
 * but the alpha value is a gx_color_value.  This is a design flaw that
 * we might be able to fix eventually.
 */

/* Render a gray, possibly by halftoning. */
/* Return 0 if complete, 1 if caller must do gx_color_load, <0 on error. */
int gx_render_device_gray(P6(frac gray, gx_color_value alpha,
			     gx_device_color * pdevc, gx_device * dev,
			     gx_device_halftone * dev_ht,
			     const gs_int_point * ht_phase));

#define gx_render_gray_alpha(gray, alpha, pdevc, pis, dev, select)\
  gx_render_device_gray(gray, alpha, pdevc, dev, pis->dev_ht,\
			&pis->screen_phase[select])
#define gx_render_gray(gray, pdevc, pis, dev, select)\
  gx_render_gray_alpha(gray, pis->alpha, pdevc, pis, dev, select)

/* Render a color, possibly by halftoning. */
/* Return as for gx_render_[device_]gray. */
int gx_render_device_color(P10(frac red, frac green, frac blue, frac white,
			       bool cmyk, gx_color_value alpha,
			       gx_device_color * pdevc, gx_device * dev,
			       gx_device_halftone * pdht,
			       const gs_int_point * ht_phase));

#define gx_render_color_alpha(r, g, b, w, a, cmyk, pdevc, pis, dev, select)\
  gx_render_device_color(r, g, b, w, cmyk, a, pdevc, dev,\
			 pis->dev_ht, &pis->screen_phase[select])
#define gx_render_color(r, g, b, w, cmyk, pdevc, pis, dev, select)\
  gx_render_color_alpha(r, g, b, w, pis->alpha, cmyk, pdevc, pis, dev, select)
#define gx_render_rgb(r, g, b, pdevc, pis, dev, select)\
  gx_render_color(r, g, b, frac_0, false, pdevc, pis, dev, select)
#define gx_render_cmyk(c, m, y, k, pdevc, pis, dev, select)\
  gx_render_color(c, m, y, k, true, pdevc, pis, dev, select)
#define gx_render_rgb_alpha(r, g, b, a, pdevc, pis, dev, select)\
  gx_render_color_alpha(r, g, b, frac_0, a, false, pdevc, pis, dev, select)

/*
 * Reduce a colored halftone with 0 or 1 varying plane(s) to a pure color
 * or a binary halftone.
 */
int gx_reduce_colored_halftone(P3(gx_device_color *pdevc, gx_device *dev,
				  bool cmyk));

#endif /* gxdither_INCLUDED */
