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  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
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*/

/* gdevht.h */
/* Definitions for halftoning device */
/* Requires gxdevice.h */
#include "gzht.h"

/*
 * A halftoning device converts between a non-halftoned device color space
 * (e.g., 8-bit gray) and a halftoned space (e.g., 1-bit black and white).
 * Currently, the target space must not exceed 8 bits per pixel, so that
 * we can pack two target colors and a halftone level into a gx_color_index.
 */
#define ht_target_max_depth 8
#define ht_level_depth (sizeof(gx_color_index) * 8 - ht_target_max_depth * 2)
typedef struct gx_device_ht_s {
	gx_device_forward_common;
		/* Following are set before opening. */
	const gx_device_halftone *dev_ht;
	gs_int_point ht_phase;		/* halftone phase from gstate */
		/* Following are computed when device is opened. */
	gs_int_point phase;		/* halftone tile offset */
} gx_device_ht;

/* Macro for casting gx_device argument */
#define htdev ((gx_device_ht *)dev)