scummvm/scumm/bomp.cpp
2003-08-18 15:13:15 +00:00

389 lines
9.2 KiB
C++

/* ScummVM - Scumm Interpreter
* Copyright (C) 2001 Ludvig Strigeus
* Copyright (C) 2001-2003 The ScummVM project
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* $Header$
*
*/
#include "stdafx.h"
#include "scumm.h"
#include "akos.h"
#include "bomp.h"
static void bompScaleFuncX(byte *line_buffer, byte *scaling_x_ptr, byte skip, int32 size);
static void bompApplyShadow0(const byte *line_buffer, byte *dst, int32 size, byte transparency);
static void bompApplyShadow1(const byte *shadowPalette, const byte *line_buffer, byte *dst, int32 size, byte transparency);
static void bompApplyShadow3(const byte *shadowPalette, const byte *line_buffer, byte *dst, int32 size, byte transparency);
static void bompApplyActorPalette(byte *actorPalette, byte *line_buffer, int32 size);
void decompressBomp(byte *dst, const byte *src, int w, int h) {
assert(w > 0);
assert(h > 0);
do {
bompDecodeLine(dst, src + 2, w);
src += READ_LE_UINT16(src) + 2;
dst += w;
} while (--h);
}
void bompDecodeLine(byte *dst, const byte *src, int size) {
assert(size > 0);
int len, num;
byte code, color;
len = size;
while (len) {
code = *src++;
num = (code >> 1) + 1;
if (num > len)
num = len;
len -= num;
if (code & 1) {
color = *src++;
memset(dst, color, num);
} else {
memcpy(dst, src, num);
src += num;
}
dst += num;
}
}
void bompDecodeLineReverse(byte *dst, const byte *src, int size) {
assert(size > 0);
dst += size;
int len, num;
byte code, color;
len = size;
while (len) {
code = *src++;
num = (code >> 1) + 1;
if (num > len)
num = len;
len -= num;
dst -= num;
if (code & 1) {
color = *src++;
memset(dst, color, num);
} else {
memcpy(dst, src, num);
src += num;
}
}
}
void bompApplyMask(byte *line_buffer, byte *mask, byte maskbit, int32 size, byte transparency) {
while (1) {
do {
if (size-- == 0)
return;
if (*mask & maskbit) {
*line_buffer = transparency;
}
line_buffer++;
maskbit >>= 1;
} while (maskbit);
mask++;
maskbit = 128;
}
}
void bompApplyShadow(int shadowMode, const byte *shadowPalette, const byte *line_buffer, byte *dst, int32 size, byte transparency) {
assert(size > 0);
switch(shadowMode) {
case 0:
bompApplyShadow0(line_buffer, dst, size, transparency);
break;
case 1:
bompApplyShadow1(shadowPalette, line_buffer, dst, size, transparency);
break;
case 3:
bompApplyShadow3(shadowPalette, line_buffer, dst, size, transparency);
break;
default:
error("Unknown shadow mode %d", shadowMode);
}
}
void bompApplyShadow0(const byte *line_buffer, byte *dst, int32 size, byte transparency) {
while (size-- > 0) {
byte tmp = *line_buffer++;
if (tmp != transparency) {
*dst = tmp;
}
dst++;
}
}
void bompApplyShadow1(const byte *shadowPalette, const byte *line_buffer, byte *dst, int32 size, byte transparency) {
while (size-- > 0) {
byte tmp = *line_buffer++;
if (tmp != transparency) {
if (tmp == 13) {
tmp = shadowPalette[*dst];
}
*dst = tmp;
}
dst++;
}
}
void bompApplyShadow3(const byte *shadowPalette, const byte *line_buffer, byte *dst, int32 size, byte transparency) {
while (size-- > 0) {
byte tmp = *line_buffer++;
if (tmp != transparency) {
if (tmp < 8) {
tmp = shadowPalette[*dst + (tmp << 8)];
}
*dst = tmp;
}
dst++;
}
}
void bompApplyActorPalette(byte *actorPalette, byte *line_buffer, int32 size) {
if (actorPalette != 0) {
actorPalette[255] = 255;
while (size-- > 0) {
*line_buffer = actorPalette[*line_buffer];
line_buffer++;
}
}
}
void bompScaleFuncX(byte *line_buffer, byte *scaling_x_ptr, byte skip, int32 size) {
byte *line_ptr1 = line_buffer;
byte *line_ptr2 = line_buffer;
byte tmp = *scaling_x_ptr++;
while (size--) {
if ((skip & tmp) == 0) {
*line_ptr1++ = *line_ptr2;
}
line_ptr2++;
skip >>= 1;
if (skip == 0) {
skip = 128;
tmp = *scaling_x_ptr++;
}
}
}
void Scumm::drawBomp(const BompDrawData &bd, bool mirror) {
const byte *src;
byte *dst;
byte maskbit;
byte *mask = 0;
byte *charset_mask;
int clip_left, clip_right, clip_top, clip_bottom;
byte *scalingYPtr = bd.scalingYPtr;
byte skip_y_bits = 0x80;
byte skip_y_new = 0;
byte tmp;
if (bd.x < 0) {
clip_left = -bd.x;
} else {
clip_left = 0;
}
if (bd.y < 0) {
clip_top = -bd.y;
} else {
clip_top = 0;
}
clip_right = bd.srcwidth;
if (clip_right > bd.outwidth - bd.x) {
clip_right = bd.outwidth - bd.x;
}
clip_bottom = bd.srcheight;
if (clip_bottom > bd.outheight - bd.y) {
clip_bottom = bd.outheight - bd.y;
}
src = bd.dataptr;
dst = bd.out + bd.y * bd.outwidth + bd.x + clip_left;
maskbit = revBitMask[(bd.x + clip_left) & 7];
// Always mask against the charset mask
charset_mask = getMaskBuffer(bd.x + clip_left, bd.y, 0);
// Also mask against any additionally imposed mask
if (bd.maskPtr) {
mask = bd.maskPtr + (bd.y * gdi._numStrips) + ((bd.x + clip_left) >> 3);
}
// Setup vertical scaling
if (bd.scale_y != 255) {
assert(scalingYPtr);
skip_y_new = *scalingYPtr++;
skip_y_bits = 0x80;
if (clip_bottom > bd.scaleBottom) {
clip_bottom = bd.scaleBottom;
}
}
// Setup horizontal scaling
if (bd.scale_x != 255) {
assert(bd.scalingXPtr);
if (clip_right > bd.scaleRight) {
clip_right = bd.scaleRight;
}
}
const int width = clip_right - clip_left;
if (width <= 0)
return;
int pos_y = 0;
byte line_buffer[1024];
byte *line_ptr = line_buffer + clip_left;
// Loop over all lines
while (pos_y < clip_bottom) {
// Decode a single (bomp encoded) line, reversed if we are in mirror mode
if (mirror)
bompDecodeLineReverse(line_buffer, src + 2, bd.srcwidth);
else
bompDecodeLine(line_buffer, src + 2, bd.srcwidth);
src += READ_LE_UINT16(src) + 2;
// If vertical scaling is enabled, do it
if (bd.scale_y != 255) {
// A bit set means we should skip this line...
tmp = skip_y_new & skip_y_bits;
// Advance the scale-skip bit mask, if it's 0, get the next scale-skip byte
skip_y_bits >>= 1;
if (skip_y_bits == 0) {
skip_y_bits = 0x80;
skip_y_new = *scalingYPtr++;
}
// Skip the current line if the above check tells us to
if (tmp != 0)
continue;
}
// Perform horizontal scaling
if (bd.scale_x != 255) {
bompScaleFuncX(line_buffer, bd.scalingXPtr, 0x80, bd.srcwidth);
}
// The first clip_top lines are to be clipped, i.e. not drawn
if (clip_top > 0) {
clip_top--;
} else {
// Replace the parts of the line which are masked with the transparency color
if (bd.maskPtr)
bompApplyMask(line_ptr, mask, maskbit, width, 255);
bompApplyMask(line_ptr, charset_mask, maskbit, width, 255);
// Apply custom color map, if available
if (_bompActorPalettePtr)
bompApplyActorPalette(_bompActorPalettePtr, line_ptr, width);
// Finally, draw the decoded, scaled, masked and recolored line onto
// the target surface, using the specified shadow mode
bompApplyShadow(bd.shadowMode, _shadowPalette, line_ptr, dst, width, 255);
}
// Advance to the next line
pos_y++;
mask += gdi._numStrips;
charset_mask += gdi._numStrips;
dst += bd.outwidth;
}
}
static const byte bitCount[] = {
8, 7, 7, 6, 7, 6, 6, 5, 7, 6, 6, 5, 6, 5, 5, 4,
7, 6, 6, 5, 6, 5, 5, 4, 6, 5, 5, 4, 5, 4, 4, 3,
7, 6, 6, 5, 6, 5, 5, 4, 6, 5, 5, 4, 5, 4, 4, 3,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
7, 6, 6, 5, 6, 5, 5, 4, 6, 5, 5, 4, 5, 4, 4, 3,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1,
7, 6, 6, 5, 6, 5, 5, 4, 6, 5, 5, 4, 5, 4, 4, 3,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1,
6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2,
5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1,
5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1,
4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0,
};
int32 setupBompScale(byte *scaling, int32 size, byte scale) {
byte tmp;
int32 count;
const byte *tmp_ptr;
byte *tmp_scaling = scaling;
byte a = 0;
byte ret_value = 0;
const int offsets[8] = { 3, 2, 1, 0, 7, 6, 5, 4 };
count = (256 - (size >> 1));
assert(0 <= count && count < 768);
tmp_ptr = defaultScaleTable + count;
count = (size + 7) >> 3;
while (count--) {
a = 0;
for (int i = 0; i < 8; i++) {
tmp = *(tmp_ptr + offsets[i]);
a <<= 1;
if (scale < tmp) {
a |= 1;
}
}
tmp_ptr += 8;
*tmp_scaling++ = a;
}
if ((size & 7) != 0) {
*(tmp_scaling - 1) |= revBitMask[size & 7];
}
count = (size + 7) >> 3;
while (count--) {
tmp = *scaling++;
ret_value += bitCount[tmp];
}
return ret_value;
}