scummvm/graphics/iff.cpp
2011-05-12 01:16:22 +02:00

272 lines
6.4 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include "graphics/iff.h"
#include "graphics/surface.h"
#include "common/endian.h"
#include "common/func.h"
#include "common/iff_container.h"
#include "common/textconsole.h"
#include "common/util.h"
namespace Graphics {
void BMHD::load(Common::ReadStream *stream) {
assert(stream);
stream->read(this, sizeof(BMHD));
width = FROM_BE_16(width);
height = FROM_BE_16(height);
x = FROM_BE_16(x);
y = FROM_BE_16(y);
transparentColor = FROM_BE_16(transparentColor);
pageWidth = FROM_BE_16(pageWidth);
pageHeight = FROM_BE_16(pageHeight);
}
void ILBMDecoder::loadHeader(Common::ReadStream *stream) {
_header.load(stream);
}
void ILBMDecoder::loadBitmap(uint32 mode, byte *buffer, Common::ReadStream *stream) {
assert(stream);
uint32 numPlanes = MIN(mode & ILBM_UNPACK_PLANES, (uint32)_header.depth);
assert(numPlanes == 1 || numPlanes == 2 || numPlanes == 3 || numPlanes == 4 || numPlanes == 5 || numPlanes == 8);
bool packPixels = (mode & ILBM_PACK_PLANES) != 0;
if (numPlanes != 1 && numPlanes != 2 && numPlanes != 4) {
packPixels = false;
}
uint32 outPitch = _header.width;
if (packPixels) {
outPitch /= (8 / numPlanes);
}
byte *out = buffer;
switch (_header.pack) {
case 1: { // PackBits compressed bitmap
Graphics::PackBitsReadStream packStream(*stream);
// setup a buffer to hold enough data to build a line in the output
uint32 scanlineWidth = ((_header.width + 15)/16) << 1;
byte *scanline = new byte[scanlineWidth * _header.depth];
for (uint i = 0; i < _header.height; ++i) {
byte *s = scanline;
for (uint32 j = 0; j < _header.depth; ++j) {
packStream.read(s, scanlineWidth);
s += scanlineWidth;
}
planarToChunky(out, outPitch, scanline, scanlineWidth, numPlanes, packPixels);
out += outPitch;
}
delete []scanline;
break;
}
default:
// implement other compression types here!
error("only RLE compressed ILBM files are supported");
break;
}
}
void ILBMDecoder::planarToChunky(byte *out, uint32 outPitch, byte *in, uint32 inWidth, uint32 nPlanes, bool packPlanes) {
byte pix, ofs, bit;
byte *s;
uint32 pixels = outPitch;
if (packPlanes) {
pixels *= (8 / nPlanes);
}
for (uint32 x = 0; x < pixels; ++x) {
pix = 0;
ofs = x >> 3;
bit = 0x80 >> (x & 7);
// first build a pixel by scanning all the usable planes in the input
s = in;
for (uint32 plane = 0; plane < nPlanes; ++plane) {
if (s[ofs] & bit) {
pix |= (1 << plane);
}
s += inWidth;
}
// then output the pixel according to the requested packing
if (!packPlanes) {
out[x] = pix;
} else
if (nPlanes == 1) {
out[x/8] |= (pix << (x & 7));
} else
if (nPlanes == 2) {
out[x/4] |= (pix << ((x & 3) << 1));
} else
if (nPlanes == 4) {
out[x/2] |= (pix << ((x & 1) << 2));
}
}
}
// handles PBM subtype of IFF FORM files
//
struct PBMDecoder {
/**
* PBM header data, necessary for loadBitmap()
*/
Graphics::BMHD _header;
/**
* Fills the _header member from the given stream.
*/
void loadHeader(Common::ReadStream *stream);
/**
* Loads and unpacks the PBM bitmap data from the stream into the buffer.
* The functions assumes the buffer is large enough to contain all data.
*/
void loadBitmap(byte *buffer, Common::ReadStream *stream);
};
void PBMDecoder::loadHeader(Common::ReadStream *stream) {
_header.load(stream);
}
void PBMDecoder::loadBitmap(byte *buffer, Common::ReadStream *stream) {
uint32 outSize = _header.width * _header.height;
switch (_header.pack) {
case 0:
stream->read(buffer, outSize);
break;
case 1: {
PackBitsReadStream packStream(*stream);
packStream.read(buffer, outSize);
break;
}
}
}
struct PBMLoader {
PBMDecoder _decoder;
Surface *_surface;
byte *_colors;
void load(Common::ReadStream &input, Surface &surface, byte *&colors) {
_surface = &surface;
_colors = colors;
Common::IFFParser parser(&input);
Common::Functor1Mem< Common::IFFChunk&, bool, PBMLoader > c(this, &PBMLoader::callback);
parser.parse(c);
}
bool callback(Common::IFFChunk &chunk) {
switch (chunk._type) {
case ID_BMHD:
_decoder.loadHeader(chunk._stream);
break;
case ID_CMAP:
if (_colors) {
chunk._stream->read(_colors, chunk._size);
}
break;
case ID_BODY:
if (_surface) {
_surface->create(_decoder._header.width, _decoder._header.height, PixelFormat::createFormatCLUT8());
_decoder.loadBitmap((byte*)_surface->pixels, chunk._stream);
}
return true; // stop the parser
}
return false;
}
};
void decodePBM(Common::ReadStream &input, Surface &surface, byte *colors) {
PBMLoader loader;
loader.load(input, surface, colors);
}
PackBitsReadStream::PackBitsReadStream(Common::ReadStream &input) : _input(&input) {
}
PackBitsReadStream::~PackBitsReadStream() {
}
bool PackBitsReadStream::eos() const {
return _input->eos();
}
uint32 PackBitsReadStream::read(void *dataPtr, uint32 dataSize) {
byte *out = (byte*)dataPtr;
uint32 left = dataSize;
uint32 lenR = 0, lenW = 0;
while (left > 0 && !_input->eos()) {
lenR = _input->readByte();
if (lenR == 128) {
// no-op
lenW = 0;
} else if (lenR <= 127) {
// literal run
lenR++;
lenW = MIN(lenR, left);
for (uint32 j = 0; j < lenW; j++) {
*out++ = _input->readByte();
}
for ( ; lenR > lenW; lenR--) {
_input->readByte();
}
} else { // len > 128
// expand run
lenW = MIN((256 - lenR) + 1, left);
byte val = _input->readByte();
memset(out, val, lenW);
out += lenW;
}
left -= lenW;
}
return dataSize - left;
}
} // End of namespace Graphics