/* Copyright (C) 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: gsptype2.c,v $ $Revision: 1.3.2.2 $ */
/* PatternType 2 implementation */
#include "gx.h"
#include "gscspace.h"
#include "gsshade.h"
#include "gsmatrix.h"		/* for gspcolor.h */
#include "gsstate.h"		/* for set/currentfilladjust */
#include "gxcolor2.h"
#include "gxdcolor.h"
#include "gsptype2.h"
#include "gxpcolor.h"
#include "gxstate.h"		/* for gs_state_memory */
#include "gzpath.h"

/* GC descriptors */
private_st_pattern2_template();
private_st_pattern2_instance();

/* GC procedures */
private ENUM_PTRS_BEGIN(pattern2_instance_enum_ptrs) {
    if (index < st_pattern2_template_max_ptrs) {
	gs_ptr_type_t ptype =
	    ENUM_SUPER_ELT(gs_pattern2_instance_t, st_pattern2_template,
			   template, 0);

	if (ptype)
	    return ptype;
	return ENUM_OBJ(NULL);	/* don't stop early */
    }
    ENUM_PREFIX(st_pattern_instance, st_pattern2_template_max_ptrs);
}
ENUM_PTRS_END
private RELOC_PTRS_BEGIN(pattern2_instance_reloc_ptrs) {
    RELOC_PREFIX(st_pattern_instance);
    RELOC_SUPER(gs_pattern2_instance_t, st_pattern2_template, template);
} RELOC_PTRS_END

/* Define a PatternType 2 pattern. */
private pattern_proc_uses_base_space(gs_pattern2_uses_base_space);
private pattern_proc_make_pattern(gs_pattern2_make_pattern);
private pattern_proc_get_pattern(gs_pattern2_get_pattern);
private pattern_proc_remap_color(gs_pattern2_remap_color);
private const gs_pattern_type_t gs_pattern2_type = {
    2, {
	gs_pattern2_uses_base_space, gs_pattern2_make_pattern,
	gs_pattern2_get_pattern, gs_pattern2_remap_color
    }
};

/* Initialize a PatternType 2 pattern. */
void
gs_pattern2_init(gs_pattern2_template_t * ppat)
{
    gs_pattern_common_init((gs_pattern_template_t *)ppat, &gs_pattern2_type);
}

/* Test whether a PatternType 2 pattern uses a base space. */
private bool
gs_pattern2_uses_base_space(const gs_pattern_template_t *ptemp)
{
    return false;
}

/* Make an instance of a PatternType 2 pattern. */
private int
gs_pattern2_make_pattern(gs_client_color * pcc,
			 const gs_pattern_template_t * pcp,
			 const gs_matrix * pmat, gs_state * pgs,
			 gs_memory_t * mem)
{
    const gs_pattern2_template_t *ptemp =
	(const gs_pattern2_template_t *)pcp;
    int code = gs_make_pattern_common(pcc, pcp, pmat, pgs, mem,
				      &st_pattern2_instance);
    gs_pattern2_instance_t *pinst;

    if (code < 0)
	return code;
    pinst = (gs_pattern2_instance_t *)pcc->pattern;
    pinst->template = *ptemp;
    return 0;
}

/* Get the template of a PatternType 2 pattern instance. */
private const gs_pattern_template_t *
gs_pattern2_get_pattern(const gs_pattern_instance_t *pinst)
{
    return (const gs_pattern_template_t *)
	&((const gs_pattern2_instance_t *)pinst)->template;
}

/* ---------------- Rendering ---------------- */

/* GC descriptor */
gs_private_st_ptrs_add0(st_dc_pattern2, gx_device_color, "dc_pattern2",
			dc_pattern2_enum_ptrs, dc_pattern2_reloc_ptrs,
			st_client_color, ccolor);

private dev_color_proc_load(gx_dc_pattern2_load);
private dev_color_proc_fill_rectangle(gx_dc_pattern2_fill_rectangle);
private dev_color_proc_equal(gx_dc_pattern2_equal);
/*
 * Define the PatternType 2 Pattern device color type.  This is public only
 * for testing when writing PDF or PostScript.
 */
const gx_device_color_type_t gx_dc_pattern2 = {
    &st_dc_pattern2,
    gx_dc_pattern2_load, gx_dc_pattern2_fill_rectangle,
    gx_dc_default_fill_masked, gx_dc_pattern2_equal
};

/* Load a PatternType 2 color into the cache.  (No effect.) */
private int
gx_dc_pattern2_load(gx_device_color *pdevc, const gs_imager_state *ignore_pis,
		    gx_device *ignore_dev, gs_color_select_t ignore_select)
{
    return 0;
}

/* Remap a PatternType 2 color. */
private int
gs_pattern2_remap_color(const gs_client_color * pc, const gs_color_space * pcs,
			gx_device_color * pdc, const gs_imager_state * pis,
			gx_device * dev, gs_color_select_t select)
{
    /* We don't do any actual color mapping now. */
    pdc->type = &gx_dc_pattern2;
    pdc->ccolor = *pc;
    return 0;
}

/* Fill a rectangle with a PatternType 2 color.  Glacially slow! */
private int
gx_dc_pattern2_fill_rectangle(const gx_device_color * pdevc, int x, int y,
			      int w, int h, gx_device * dev,
			      gs_logical_operation_t lop,
			      const gx_rop_source_t * source)
{
    gs_pattern2_instance_t *pinst =
	(gs_pattern2_instance_t *)pdevc->ccolor.pattern;
    gs_state *pgs = pinst->saved;
    gs_fixed_rect rect;
    gs_point save_adjust;
    int code;

    rect.p.x = int2fixed(x);
    rect.p.y = int2fixed(y);
    rect.q.x = int2fixed(x + w);
    rect.q.y = int2fixed(y + h);
    /* We don't want any adjustment of the box. */
    gs_currentfilladjust(pgs, &save_adjust);

    /*
     * We should set the fill adjustment to zero here, so that we don't
     * get multiply-written pixels as a result of filling abutting
     * triangles.  However, numerical inaccuracies in the shading
     * algorithms can cause pixel dropouts, and a non-zero adjustment
     * is by far the easiest way to work around them as a stopgap.
     * NOTE: This makes shadings not interact properly with
     * non-idempotent RasterOps (not a problem in practice, since
     * PostScript doesn't have RasterOps and PCL doesn't have shadings).
     */
    gs_setfilladjust(pgs, 0.5, 0.5);
    /****** DOESN'T HANDLE RASTER OP ******/
    code = gs_shading_fill_path(pinst->template.Shading, NULL, &rect, dev,
				(gs_imager_state *)pgs, true);
    gs_setfilladjust(pgs, save_adjust.x, save_adjust.y);
    return code;
}

/* Compare two PatternType 2 colors for equality. */
private bool
gx_dc_pattern2_equal(const gx_device_color * pdevc1,
		     const gx_device_color * pdevc2)
{
    return pdevc2->type == pdevc1->type &&
	pdevc1->ccolor.pattern == pdevc2->ccolor.pattern;
}
