harvey/sys/src/cmd/gs/src/zht2.c

/* Copyright (C) 1992, 1995, 1996, 1997, 1998, 1999 Aladdin Enterprises.  All rights reserved.
  
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  Every copy of AFPL Ghostscript must include a copy of the License, normally
  in a plain ASCII text file named PUBLIC.  The License grants you the right
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*/

/*$Id: zht2.c,v 1.2 2000/09/19 19:00:54 lpd Exp $ */
/* Level 2 sethalftone operator */
#include "ghost.h"
#include "oper.h"
#include "gsstruct.h"
#include "gxdevice.h"		/* for gzht.h */
#include "gzht.h"
#include "estack.h"
#include "ialloc.h"
#include "iddict.h"
#include "idparam.h"
#include "igstate.h"
#include "icolor.h"
#include "iht.h"
#include "store.h"

/* Forward references */
private int dict_spot_params(P4(const ref *, gs_spot_halftone *,
				ref *, ref *));
private int dict_spot_results(P3(i_ctx_t *, ref *, const gs_spot_halftone *));
private int dict_threshold_params(P3(const ref *, gs_threshold_halftone *,
				     ref *));
private int dict_threshold2_params(P4(const ref *, gs_threshold2_halftone *,
				      ref *, gs_memory_t *));

/* Dummy spot function */
private float
spot1_dummy(floatp x, floatp y)
{
    return (x + y) / 2;
}

/* <dict> <dict5> .sethalftone5 - */
private int sethalftone_finish(P1(i_ctx_t *));
private int sethalftone_cleanup(P1(i_ctx_t *));
private int
zsethalftone5(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    uint count;
    gs_halftone_component *phtc;
    gs_halftone_component *pc;
    int code = 0;
    int i, j;
    gs_halftone *pht;
    gx_device_halftone *pdht;
    static const char *const color_names[] = {
	gs_ht_separation_name_strings
    };
    ref sprocs[countof(color_names)];
    ref tprocs[countof(color_names)];
    gs_memory_t *mem;
    uint edepth = ref_stack_count(&e_stack);
    int npop = 2;

    check_type(*op, t_dictionary);
    check_dict_read(*op);
    check_type(op[-1], t_dictionary);
    check_dict_read(op[-1]);
    count = 0;
    for (i = 0; i < countof(color_names); i++) {
	ref *pvalue;

	if (dict_find_string(op, color_names[i], &pvalue) > 0)
	    count++;
	else if (i == gs_ht_separation_Default)
	    return_error(e_typecheck);
    }
    mem = (gs_memory_t *) idmemory->spaces_indexed[r_space_index(op - 1)];
    check_estack(5);		/* for sampling Type 1 screens */
    refset_null(sprocs, countof(sprocs));
    refset_null(tprocs, countof(tprocs));
    rc_alloc_struct_0(pht, gs_halftone, &st_halftone,
		      imemory, pht = 0, ".sethalftone5");
    phtc = gs_alloc_struct_array(mem, count, gs_halftone_component,
				 &st_ht_component_element,
				 ".sethalftone5");
    rc_alloc_struct_0(pdht, gx_device_halftone, &st_device_halftone,
		      imemory, pdht = 0, ".sethalftone5");
    if (pht == 0 || phtc == 0 || pdht == 0)
	code = gs_note_error(e_VMerror);
    else
	for (i = 0, j = 0, pc = phtc; i < countof(color_names); i++) {
	    int type;
	    ref *pvalue;

	    if (dict_find_string(op, color_names[i], &pvalue) > 0) {
		check_type_only(*pvalue, t_dictionary);
		check_dict_read(*pvalue);
		if (dict_int_param(pvalue, "HalftoneType", 1, 7, 0,
				   &type) < 0
		    ) {
		    code = gs_note_error(e_typecheck);
		    break;
		}
		switch (type) {
		    default:
			code = gs_note_error(e_rangecheck);
			break;
		    case 1:
			code = dict_spot_params(pvalue,
						&pc->params.spot, sprocs + j,
						tprocs + j);
			pc->params.spot.screen.spot_function = spot1_dummy;
			pc->type = ht_type_spot;
			break;
		    case 3:
			code = dict_threshold_params(pvalue,
					 &pc->params.threshold, tprocs + j);
			pc->type = ht_type_threshold;
			break;
		    case 7:
			code = dict_threshold2_params(pvalue,
					&pc->params.threshold2, tprocs + j,
					imemory);
			pc->type = ht_type_threshold2;
			break;
		}
		if (code < 0)
		    break;
		pc->cname = (gs_ht_separation_name) i;
		pc++, j++;
	    }
	}
    if (code >= 0) {
	/*
	 * We think that Type 2 and Type 4 halftones, like
	 * screens set by setcolorscreen, adapt automatically to
	 * the device color space, so we need to mark them
	 * with a different internal halftone type.
	 */
	int type = 0;

	dict_int_param(op - 1, "HalftoneType", 1, 5, 0, &type);
	pht->type =
	    (type == 2 || type == 4 ? ht_type_multiple_colorscreen :
	     ht_type_multiple);
	pht->params.multiple.components = phtc;
	pht->params.multiple.num_comp = count;
	code = gs_sethalftone_prepare(igs, pht, pdht);
    }
    if (code >= 0)
	for (j = 0, pc = phtc; j < count; j++, pc++) {
	    if (pc->type == ht_type_spot) {
		ref *pvalue;

		dict_find_string(op, color_names[pc->cname], &pvalue);
		code = dict_spot_results(i_ctx_p, pvalue, &pc->params.spot);
		if (code < 0)
		    break;
	    }
	}
    if (code >= 0) {
	/*
	 * Schedule the sampling of any Type 1 screens,
	 * and any (Type 1 or Type 3) TransferFunctions.
	 * Save the stack depths in case we have to back out.
	 */
	uint odepth = ref_stack_count(&o_stack);
	ref odict, odict5;

	odict = op[-1];
	odict5 = *op;
	pop(2);
	op = osp;
	esp += 5;
	make_mark_estack(esp - 4, es_other, sethalftone_cleanup);
	esp[-3] = odict;
	make_istruct(esp - 2, 0, pht);
	make_istruct(esp - 1, 0, pdht);
	make_op_estack(esp, sethalftone_finish);
	for (j = 0; j < count; j++) {
	    gx_ht_order *porder =
	    (pdht->components == 0 ? &pdht->order :
	     &pdht->components[j].corder);

	    switch (phtc[j].type) {
		case ht_type_spot:
		    code = zscreen_enum_init(i_ctx_p, porder,
					     &phtc[j].params.spot.screen,
					     &sprocs[j], 0, 0, mem);
		    if (code < 0)
			break;
		    /* falls through */
		case ht_type_threshold:
		    if (!r_has_type(tprocs + j, t__invalid)) {
			/* Schedule TransferFunction sampling. */
			/****** check_xstack IS WRONG ******/
			check_ostack(zcolor_remap_one_ostack);
			check_estack(zcolor_remap_one_estack);
			code = zcolor_remap_one(i_ctx_p, tprocs + j,
						porder->transfer, igs,
						zcolor_remap_one_finish);
			op = osp;
		    }
		    break;
		default:	/* not possible here, but to keep */
		    /* the compilers happy.... */
		    ;
	    }
	    if (code < 0) {	/* Restore the stack. */
		ref_stack_pop_to(&o_stack, odepth);
		ref_stack_pop_to(&e_stack, edepth);
		op = osp;
		op[-1] = odict;
		*op = odict5;
		break;
	    }
	    npop = 0;
	}
    }
    if (code < 0) {
	gs_free_object(mem, pdht, ".sethalftone5");
	gs_free_object(mem, phtc, ".sethalftone5");
	gs_free_object(mem, pht, ".sethalftone5");
	return code;
    }
    pop(npop);
    return (ref_stack_count(&e_stack) > edepth ? o_push_estack : 0);
}
/* Install the halftone after sampling. */
private int
sethalftone_finish(i_ctx_t *i_ctx_p)
{
    gx_device_halftone *pdht = r_ptr(esp, gx_device_halftone);
    int code;

    if (pdht->components)
	pdht->order = pdht->components[0].corder;
    code = gx_ht_install(igs, r_ptr(esp - 1, gs_halftone), pdht);
    if (code < 0)
	return code;
    istate->halftone = esp[-2];
    esp -= 4;
    sethalftone_cleanup(i_ctx_p);
    return o_pop_estack;
}
/* Clean up after installing the halftone. */
private int
sethalftone_cleanup(i_ctx_t *i_ctx_p)
{
    gx_device_halftone *pdht = r_ptr(&esp[4], gx_device_halftone);
    gs_halftone *pht = r_ptr(&esp[3], gs_halftone);

    gs_free_object(pdht->rc.memory, pdht,
		   "sethalftone_cleanup(device halftone)");
    gs_free_object(pht->rc.memory, pht,
		   "sethalftone_cleanup(halftone)");
    return 0;
}

/* ------ Initialization procedure ------ */

const op_def zht2_l2_op_defs[] =
{
    op_def_begin_level2(),
    {"2.sethalftone5", zsethalftone5},
		/* Internal operators */
    {"0%sethalftone_finish", sethalftone_finish},
    op_def_end(0)
};

/* ------ Internal routines ------ */

/* Extract frequency, angle, spot function, and accurate screens flag */
/* from a dictionary. */
private int
dict_spot_params(const ref * pdict, gs_spot_halftone * psp,
		 ref * psproc, ref * ptproc)
{
    int code;

    check_dict_read(*pdict);
    if ((code = dict_float_param(pdict, "Frequency", 0.0,
				 &psp->screen.frequency)) != 0 ||
	(code = dict_float_param(pdict, "Angle", 0.0,
				 &psp->screen.angle)) != 0 ||
      (code = dict_proc_param(pdict, "SpotFunction", psproc, false)) != 0 ||
	(code = dict_bool_param(pdict, "AccurateScreens",
				gs_currentaccuratescreens(),
				&psp->accurate_screens)) < 0 ||
      (code = dict_proc_param(pdict, "TransferFunction", ptproc, false)) < 0
	)
	return (code < 0 ? code : e_undefined);
    psp->transfer = (code > 0 ? (gs_mapping_proc) 0 : gs_mapped_transfer);
    psp->transfer_closure.proc = 0;
    psp->transfer_closure.data = 0;
    return 0;
}

/* Set actual frequency and angle in a dictionary. */
private int
dict_real_result(i_ctx_t *i_ctx_p, ref * pdict, const char *kstr, floatp val)
{
    int code = 0;
    ref *ignore;

    if (dict_find_string(pdict, kstr, &ignore) > 0) {
	ref rval;

	check_dict_write(*pdict);
	make_real(&rval, val);
	code = idict_put_string(pdict, kstr, &rval);
    }
    return code;
}
private int
dict_spot_results(i_ctx_t *i_ctx_p, ref * pdict, const gs_spot_halftone * psp)
{
    int code;

    code = dict_real_result(i_ctx_p, pdict, "ActualFrequency",
			    psp->screen.actual_frequency);
    if (code < 0)
	return code;
    return dict_real_result(i_ctx_p, pdict, "ActualAngle",
			    psp->screen.actual_angle);
}

/* Extract Width, Height, and TransferFunction from a dictionary. */
private int
dict_threshold_common_params(const ref * pdict,
			     gs_threshold_halftone_common * ptp,
			     ref **pptstring, ref *ptproc)
{
    int code;

    check_dict_read(*pdict);
    if ((code = dict_int_param(pdict, "Width", 1, 0x7fff, -1,
			       &ptp->width)) < 0 ||
	(code = dict_int_param(pdict, "Height", 1, 0x7fff, -1,
			       &ptp->height)) < 0 ||
	(code = dict_find_string(pdict, "Thresholds", pptstring)) <= 0 ||
      (code = dict_proc_param(pdict, "TransferFunction", ptproc, false)) < 0
	)
	return (code < 0 ? code : e_undefined);
    ptp->transfer_closure.proc = 0;
    ptp->transfer_closure.data = 0;
    return code;
}

/* Extract threshold common parameters + Thresholds. */
private int
dict_threshold_params(const ref * pdict, gs_threshold_halftone * ptp,
		      ref * ptproc)
{
    ref *tstring;
    int code =
	dict_threshold_common_params(pdict,
				     (gs_threshold_halftone_common *)ptp,
				     &tstring, ptproc);

    if (code < 0)
	return code;
    check_read_type_only(*tstring, t_string);
    if (r_size(tstring) != (long)ptp->width * ptp->height)
	return_error(e_rangecheck);
    ptp->thresholds.data = tstring->value.const_bytes;
    ptp->thresholds.size = r_size(tstring);
    ptp->transfer = (code > 0 ? (gs_mapping_proc) 0 : gs_mapped_transfer);
    return 0;
}

/* Extract threshold common parameters + Thresholds, Width2, Height2, */
/* BitsPerSample. */
private int
dict_threshold2_params(const ref * pdict, gs_threshold2_halftone * ptp,
		       ref * ptproc, gs_memory_t *mem)
{
    ref *tstring;
    int code =
	dict_threshold_common_params(pdict,
				     (gs_threshold_halftone_common *)ptp,
				     &tstring, ptproc);
    int bps;
    uint size;
    int cw2, ch2;

    if (code < 0 ||
	(code = cw2 = dict_int_param(pdict, "Width2", 0, 0x7fff, 0,
				     &ptp->width2)) < 0 ||
	(code = ch2 = dict_int_param(pdict, "Height2", 0, 0x7fff, 0,
				     &ptp->height2)) < 0 ||
	(code = dict_int_param(pdict, "BitsPerSample", 8, 16, -1, &bps)) < 0
	)
	return code;
    if ((bps != 8 && bps != 16) || cw2 != ch2 ||
	(!cw2 && (ptp->width2 == 0 || ptp->height2 == 0))
	)
	return_error(e_rangecheck);
    ptp->bytes_per_sample = bps / 8;
    switch (r_type(tstring)) {
    case t_string:
	size = r_size(tstring);
	gs_bytestring_from_string(&ptp->thresholds, tstring->value.const_bytes,
				  size);
	break;
    case t_astruct:
	if (gs_object_type(mem, tstring->value.pstruct) != &st_bytes)
	    return_error(e_typecheck);
	size = gs_object_size(mem, tstring->value.pstruct);
	gs_bytestring_from_bytes(&ptp->thresholds, r_ptr(tstring, byte),
				 0, size);
	break;
    default:
	return_error(e_typecheck);
    }
    check_read(*tstring);
    if (size != (ptp->width * ptp->height + ptp->width2 * ptp->height2) *
	ptp->bytes_per_sample)
	return_error(e_rangecheck);
    return 0;
}