/* Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999 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: gdevm24.c,v 1.4 2002/02/21 22:24:51 giles Exp $ */
/* 24-bit-per-pixel "memory" (stored bitmap) device */
#include "memory_.h"
#include "gx.h"
#include "gxdevice.h"
#include "gxdevmem.h"		/* semi-public definitions */
#include "gdevmem.h"		/* private definitions */

#define mem_true24_strip_copy_rop mem_gray8_rgb24_strip_copy_rop

/*
 * Define whether to use the library's memset.
 */
/*#define USE_MEMSET*/
/*
 * Define whether to use memcpy for very wide fills.  We thought this
 * made a big difference, but it turned out to be an artifact of the
 * profiler.
 */
/*#define USE_MEMCPY*/

/* Define debugging statistics. */
#ifdef DEBUG
struct stats_mem24_s {
    long
	fill, fwide, fgray[101], fsetc, fcolor[101], fnarrow[5],
	fprevc[257];
    double ftotal;
} stats_mem24;
static int prev_count;
static uint prev_colors[256];
# define INCR(v) (++(stats_mem24.v))
#else
# define INCR(v) DO_NOTHING
#endif


/* ================ Standard (byte-oriented) device ================ */

#undef chunk
#define chunk byte

/* Procedures */
declare_mem_procs(mem_true24_copy_mono, mem_true24_copy_color, mem_true24_fill_rectangle);
private dev_proc_copy_alpha(mem_true24_copy_alpha);

/* The device descriptor. */
const gx_device_memory mem_true24_device =
mem_full_alpha_device("image24", 24, 0, mem_open,
		 gx_default_rgb_map_rgb_color, gx_default_rgb_map_color_rgb,
     mem_true24_copy_mono, mem_true24_copy_color, mem_true24_fill_rectangle,
		      gx_default_map_cmyk_color, mem_true24_copy_alpha,
		 gx_default_strip_tile_rectangle, mem_true24_strip_copy_rop,
		      mem_get_bits_rectangle);

/* Convert x coordinate to byte offset in scan line. */
#undef x_to_byte
#define x_to_byte(x) ((x) * 3)

/* Unpack a color into its bytes. */
#define declare_unpack_color(r, g, b, color)\
	byte r = (byte)(color >> 16);\
	byte g = (byte)((uint)color >> 8);\
	byte b = (byte)color
/* Put a 24-bit color into the bitmap. */
#define put3(ptr, r, g, b)\
	(ptr)[0] = r, (ptr)[1] = g, (ptr)[2] = b
/* Put 4 bytes of color into the bitmap. */
#define putw(ptr, wxyz)\
	*(bits32 *)(ptr) = (wxyz)
/* Load the 3-word 24-bit-color cache. */
/* Free variables: [m]dev, rgbr, gbrg, brgb. */
#if arch_is_big_endian
#  define set_color24_cache(crgb, r, g, b)\
	mdev->color24.rgbr = rgbr = ((bits32)(crgb) << 8) | (r),\
	mdev->color24.gbrg = gbrg = (rgbr << 8) | (g),\
	mdev->color24.brgb = brgb = (gbrg << 8) | (b),\
	mdev->color24.rgb = (crgb)
#else
#  define set_color24_cache(crgb, r, g, b)\
	mdev->color24.rgbr = rgbr =\
		((bits32)(r) << 24) | ((bits32)(b) << 16) |\
		((bits16)(g) << 8) | (r),\
	mdev->color24.brgb = brgb = (rgbr << 8) | (b),\
	mdev->color24.gbrg = gbrg = (brgb << 8) | (g),\
	mdev->color24.rgb = (crgb)
#endif

/* Fill a rectangle with a color. */
private int
mem_true24_fill_rectangle(gx_device * dev,
			  int x, int y, int w, int h, gx_color_index color)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    declare_unpack_color(r, g, b, color);
    declare_scan_ptr(dest);

    /*
     * In order to avoid testing w > 0 and h > 0 twice, we defer
     * executing setup_rect, and use fit_fill_xywh instead of
     * fit_fill.
     */
    fit_fill_xywh(dev, x, y, w, h);
    INCR(fill);
#ifdef DEBUG
    stats_mem24.ftotal += w;
#endif
    if (w >= 5) {
	if (h <= 0)
	    return 0;
	INCR(fwide);
	setup_rect(dest);
	if (r == g && r == b) {
#ifndef USE_MEMSET
	    /* We think we can do better than the library's memset.... */
	    int bcntm7 = w * 3 - 7;
	    register bits32 cword = color | (color << 24);

	    INCR(fgray[min(w, 100)]);
	    while (h-- > 0) {
		register byte *pptr = dest;
		byte *limit = pptr + bcntm7;

		/* We want to store full words, but we have to */
		/* guarantee that they are word-aligned. */
		switch (x & 3) {
		    case 3:
			*pptr++ = (byte) cword;
		    case 2:
			*pptr++ = (byte) cword;
		    case 1:
			*pptr++ = (byte) cword;
		    case 0:;
		}
		/* Even with w = 5, we always store at least */
		/* 3 full words, regardless of the starting x. */
		*(bits32 *) pptr =
		    ((bits32 *) pptr)[1] =
		    ((bits32 *) pptr)[2] = cword;
		pptr += 12;
		while (pptr < limit) {
		    *(bits32 *) pptr =
			((bits32 *) pptr)[1] = cword;
		    pptr += 8;
		}
		switch ((int)(pptr - limit)) {
		    case 0:
			pptr[6] = (byte) cword;
		    case 1:
			pptr[5] = (byte) cword;
		    case 2:
			pptr[4] = (byte) cword;
		    case 3:
			*(bits32 *) pptr = cword;
			break;
		    case 4:
			pptr[2] = (byte) cword;
		    case 5:
			pptr[1] = (byte) cword;
		    case 6:
			pptr[0] = (byte) cword;
		    case 7:;
		}
		inc_ptr(dest, draster);
	    }
#else
	    int bcnt = w * 3;

	    INCR(fgray[min(w, 100)]);
	    while (h-- > 0) {
		memset(dest, r, bcnt);
		inc_ptr(dest, draster);
	    }
#endif
	} else {
	    int x3 = -x & 3, ww = w - x3;	/* we know ww >= 2 */
	    bits32 rgbr, gbrg, brgb;

	    if (mdev->color24.rgb == color) {
		rgbr = mdev->color24.rgbr;
		gbrg = mdev->color24.gbrg;
		brgb = mdev->color24.brgb;
	    } else {
		INCR(fsetc);
		set_color24_cache(color, r, g, b);
	    }
#ifdef DEBUG
	    {
		int ci;
		for (ci = 0; ci < prev_count; ++ci)
		    if (prev_colors[ci] == color)
			break;
		INCR(fprevc[ci]);
		if (ci == prev_count) {
		    if (ci < countof(prev_colors))
			++prev_count;
		    else
			--ci;
		}
		if (ci) {
		    memmove(&prev_colors[1], &prev_colors[0],
			    ci * sizeof(prev_colors[0]));
		    prev_colors[0] = color;
		}
	    }
#endif
	    INCR(fcolor[min(w, 100)]);
	    while (h-- > 0) {
		register byte *pptr = dest;
		int w1 = ww;

		switch (x3) {
		    case 1:
			put3(pptr, r, g, b);
			pptr += 3;
			break;
		    case 2:
			pptr[0] = r;
			pptr[1] = g;
			putw(pptr + 2, brgb);
			pptr += 6;
			break;
		    case 3:
			pptr[0] = r;
			putw(pptr + 1, gbrg);
			putw(pptr + 5, brgb);
			pptr += 9;
			break;
		    case 0:
			;
		}
#ifdef USE_MEMCPY
		/*
		 * For very wide fills, it's most efficient to fill a few
		 * pixels and then use memcpy to fill the rest.
		 */
		if (w1 > 16) {
#define PUTW4(ptr, w)\
  BEGIN\
    putw(ptr, w); putw((ptr)+12, w); putw((ptr)+24, w); putw((ptr)+36, w);\
  END
		    PUTW4(pptr, rgbr);
		    PUTW4(pptr + 4, gbrg);
		    PUTW4(pptr + 8, brgb);
#undef PUTW4
		    if (w1 > 64) {
			memcpy(pptr + 48, pptr, 48);
			memcpy(pptr + 96, pptr, 96);
			for (pptr += 192; (w1 -= 64) >= 64; pptr += 192)
			    memcpy(pptr, pptr - 192, 192);
		    } else
			pptr += 48;
		    for (; (w1 -= 16) >= 16; pptr += 48)
			memcpy(pptr, pptr - 48, 48);
		}
#endif
		while (w1 >= 4) {
		    putw(pptr, rgbr);
		    putw(pptr + 4, gbrg);
		    putw(pptr + 8, brgb);
		    pptr += 12;
		    w1 -= 4;
		}
		switch (w1) {
		    case 1:
			put3(pptr, r, g, b);
			break;
		    case 2:
			putw(pptr, rgbr);
			pptr[4] = g;
			pptr[5] = b;
			break;
		    case 3:
			putw(pptr, rgbr);
			putw(pptr + 4, gbrg);
			pptr[8] = b;
			break;
		    case 0:
			;
		}
		inc_ptr(dest, draster);
	    }
	}
    } else if (h > 0) {		/* w < 5 */
	INCR(fnarrow[max(w, 0)]);
	setup_rect(dest);
	switch (w) {
	    case 4:
		do {
		    dest[9] = dest[6] = dest[3] = dest[0] = r;
		    dest[10] = dest[7] = dest[4] = dest[1] = g;
		    dest[11] = dest[8] = dest[5] = dest[2] = b;
		    inc_ptr(dest, draster);
		}
		while (--h);
		break;
	    case 3:
		do {
		    dest[6] = dest[3] = dest[0] = r;
		    dest[7] = dest[4] = dest[1] = g;
		    dest[8] = dest[5] = dest[2] = b;
		    inc_ptr(dest, draster);
		}
		while (--h);
		break;
	    case 2:
		do {
		    dest[3] = dest[0] = r;
		    dest[4] = dest[1] = g;
		    dest[5] = dest[2] = b;
		    inc_ptr(dest, draster);
		}
		while (--h);
		break;
	    case 1:
		do {
		    dest[0] = r, dest[1] = g, dest[2] = b;
		    inc_ptr(dest, draster);
		}
		while (--h);
		break;
	    case 0:
	    default:
		;
	}
    }
    return 0;
}

/* Copy a monochrome bitmap. */
private int
mem_true24_copy_mono(gx_device * dev,
	       const byte * base, int sourcex, int sraster, gx_bitmap_id id,
	int x, int y, int w, int h, gx_color_index zero, gx_color_index one)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    const byte *line;
    int sbit;
    int first_bit;

    declare_scan_ptr(dest);

    fit_copy(dev, base, sourcex, sraster, id, x, y, w, h);
    setup_rect(dest);
    line = base + (sourcex >> 3);
    sbit = sourcex & 7;
    first_bit = 0x80 >> sbit;
    if (zero != gx_no_color_index) {	/* Loop for halftones or inverted masks */
	/* (never used). */
	declare_unpack_color(r0, g0, b0, zero);
	declare_unpack_color(r1, g1, b1, one);
	while (h-- > 0) {
	    register byte *pptr = dest;
	    const byte *sptr = line;
	    register int sbyte = *sptr++;
	    register int bit = first_bit;
	    int count = w;

	    do {
		if (sbyte & bit) {
		    if (one != gx_no_color_index)
			put3(pptr, r1, g1, b1);
		} else
		    put3(pptr, r0, g0, b0);
		pptr += 3;
		if ((bit >>= 1) == 0)
		    bit = 0x80, sbyte = *sptr++;
	    }
	    while (--count > 0);
	    line += sraster;
	    inc_ptr(dest, draster);
	}
    } else if (one != gx_no_color_index) {	/* Loop for character and pattern masks. */
	/* This is used heavily. */
	declare_unpack_color(r1, g1, b1, one);
	int first_mask = first_bit << 1;
	int first_count, first_skip;

	if (sbit + w > 8)
	    first_mask -= 1,
		first_count = 8 - sbit;
	else
	    first_mask -= first_mask >> w,
		first_count = w;
	first_skip = first_count * 3;
	while (h-- > 0) {
	    register byte *pptr = dest;
	    const byte *sptr = line;
	    register int sbyte = *sptr++ & first_mask;
	    int count = w - first_count;

	    if (sbyte) {
		register int bit = first_bit;

		do {
		    if (sbyte & bit)
			put3(pptr, r1, g1, b1);
		    pptr += 3;
		}
		while ((bit >>= 1) & first_mask);
	    } else
		pptr += first_skip;
	    while (count >= 8) {
		sbyte = *sptr++;
		if (sbyte & 0xf0) {
		    if (sbyte & 0x80)
			put3(pptr, r1, g1, b1);
		    if (sbyte & 0x40)
			put3(pptr + 3, r1, g1, b1);
		    if (sbyte & 0x20)
			put3(pptr + 6, r1, g1, b1);
		    if (sbyte & 0x10)
			put3(pptr + 9, r1, g1, b1);
		}
		if (sbyte & 0xf) {
		    if (sbyte & 8)
			put3(pptr + 12, r1, g1, b1);
		    if (sbyte & 4)
			put3(pptr + 15, r1, g1, b1);
		    if (sbyte & 2)
			put3(pptr + 18, r1, g1, b1);
		    if (sbyte & 1)
			put3(pptr + 21, r1, g1, b1);
		}
		pptr += 24;
		count -= 8;
	    }
	    if (count > 0) {
		register int bit = 0x80;

		sbyte = *sptr++;
		do {
		    if (sbyte & bit)
			put3(pptr, r1, g1, b1);
		    pptr += 3;
		    bit >>= 1;
		}
		while (--count > 0);
	    }
	    line += sraster;
	    inc_ptr(dest, draster);
	}
    }
    return 0;
}

/* Copy a color bitmap. */
private int
mem_true24_copy_color(gx_device * dev,
	       const byte * base, int sourcex, int sraster, gx_bitmap_id id,
		      int x, int y, int w, int h)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;

    fit_copy(dev, base, sourcex, sraster, id, x, y, w, h);
    mem_copy_byte_rect(mdev, base, sourcex, sraster, x, y, w, h);
    return 0;
}

/* Copy an alpha map. */
private int
mem_true24_copy_alpha(gx_device * dev, const byte * base, int sourcex,
		   int sraster, gx_bitmap_id id, int x, int y, int w, int h,
		      gx_color_index color, int depth)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    const byte *line;

    declare_scan_ptr(dest);
    declare_unpack_color(r, g, b, color);

    fit_copy(dev, base, sourcex, sraster, id, x, y, w, h);
    setup_rect(dest);
    line = base;
    while (h-- > 0) {
	register byte *pptr = dest;
	int sx;

	for (sx = sourcex; sx < sourcex + w; ++sx, pptr += 3) {
	    int alpha2, alpha;

	    if (depth == 2)	/* map 0 - 3 to 0 - 15 */
		alpha =
		    ((line[sx >> 2] >> ((3 - (sx & 3)) << 1)) & 3) * 5;
	    else
		alpha2 = line[sx >> 1],
		    alpha = (sx & 1 ? alpha2 & 0xf : alpha2 >> 4);
	    if (alpha == 15) {	/* Just write the new color. */
		put3(pptr, r, g, b);
	    } else if (alpha != 0) {	/* Blend RGB values. */
#define make_shade(old, clr, alpha, amax) \
  (old) + (((int)(clr) - (int)(old)) * (alpha) / (amax))
		pptr[0] = make_shade(pptr[0], r, alpha, 15);
		pptr[1] = make_shade(pptr[1], g, alpha, 15);
		pptr[2] = make_shade(pptr[2], b, alpha, 15);
#undef make_shade
	    }
	}
	line += sraster;
	inc_ptr(dest, draster);
    }
    return 0;
}

/* ================ "Word"-oriented device ================ */

/* Note that on a big-endian machine, this is the same as the */
/* standard byte-oriented-device. */

#if !arch_is_big_endian

/* Procedures */
declare_mem_procs(mem24_word_copy_mono, mem24_word_copy_color, mem24_word_fill_rectangle);

/* Here is the device descriptor. */
const gx_device_memory mem_true24_word_device =
mem_full_device("image24w", 24, 0, mem_open,
		gx_default_rgb_map_rgb_color, gx_default_rgb_map_color_rgb,
     mem24_word_copy_mono, mem24_word_copy_color, mem24_word_fill_rectangle,
		gx_default_map_cmyk_color, gx_default_strip_tile_rectangle,
		gx_no_strip_copy_rop, mem_word_get_bits_rectangle);

/* Fill a rectangle with a color. */
private int
mem24_word_fill_rectangle(gx_device * dev, int x, int y, int w, int h,
			  gx_color_index color)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    byte *base;
    uint raster;

    fit_fill(dev, x, y, w, h);
    base = scan_line_base(mdev, y);
    raster = mdev->raster;
    mem_swap_byte_rect(base, raster, x * 24, w * 24, h, true);
    mem_true24_fill_rectangle(dev, x, y, w, h, color);
    mem_swap_byte_rect(base, raster, x * 24, w * 24, h, false);
    return 0;
}

/* Copy a bitmap. */
private int
mem24_word_copy_mono(gx_device * dev,
	       const byte * base, int sourcex, int sraster, gx_bitmap_id id,
	int x, int y, int w, int h, gx_color_index zero, gx_color_index one)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    byte *row;
    uint raster;
    bool store;

    fit_copy(dev, base, sourcex, sraster, id, x, y, w, h);
    row = scan_line_base(mdev, y);
    raster = mdev->raster;
    store = (zero != gx_no_color_index && one != gx_no_color_index);
    mem_swap_byte_rect(row, raster, x * 24, w * 24, h, store);
    mem_true24_copy_mono(dev, base, sourcex, sraster, id,
			 x, y, w, h, zero, one);
    mem_swap_byte_rect(row, raster, x * 24, w * 24, h, false);
    return 0;
}

/* Copy a color bitmap. */
private int
mem24_word_copy_color(gx_device * dev,
	       const byte * base, int sourcex, int sraster, gx_bitmap_id id,
		      int x, int y, int w, int h)
{
    gx_device_memory * const mdev = (gx_device_memory *)dev;
    byte *row;
    uint raster;

    fit_copy(dev, base, sourcex, sraster, id, x, y, w, h);
    row = scan_line_base(mdev, y);
    raster = mdev->raster;
    mem_swap_byte_rect(row, raster, x * 24, w * 24, h, true);
    bytes_copy_rectangle(row + x * 3, raster, base + sourcex * 3, sraster,
			 w * 3, h);
    mem_swap_byte_rect(row, raster, x * 24, w * 24, h, false);
    return 0;
}

#endif /* !arch_is_big_endian */