scummvm/image/iff.h
2021-12-26 18:48:43 +01:00

131 lines
3.8 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef IMAGE_IFF_H
#define IMAGE_IFF_H
#include "common/array.h"
#include "common/endian.h"
#include "graphics/surface.h"
#include "image/image_decoder.h"
namespace Common {
class SeekableReadStream;
}
namespace Graphics {
struct Surface;
}
namespace Image {
/**
* @defgroup image_iff IFF decoder
* @ingroup image
*
* @brief Decoder for images encoded as Interchange File Format (IFF).
*
* Used in engines:
* - Gob
* - Parallaction
* - Queen
* - Saga
* @{
*/
class IFFDecoder : public ImageDecoder {
public:
struct Header {
uint16 width, height;
uint16 x, y;
byte numPlanes;
byte masking;
byte compression;
byte flags;
uint16 transparentColor;
byte xAspect, yAspect;
uint16 pageWidth, pageHeight;
};
struct PaletteRange {
int16 timer, step, flags;
byte first, last;
};
enum Type {
TYPE_UNKNOWN = 0,
TYPE_ILBM,
TYPE_PBM
};
IFFDecoder();
virtual ~IFFDecoder();
// ImageDecoder API
void destroy();
bool loadStream(Common::SeekableReadStream &stream);
const Header *getHeader() const { return &_header; }
const Graphics::Surface *getSurface() const { return _surface; }
const byte *getPalette() const { return _palette; }
const Common::Array<PaletteRange> &getPaletteRanges() const { return _paletteRanges; }
uint16 getPaletteColorCount() const { return _paletteColorCount; }
/**
* The number of planes to decode, also determines the pixel packing if _packPixels is true.
* 8 == decode all planes, map 1 pixel in 1 byte. (default, no packing even if _packPixels is true)
*
* NOTE: this property must be reset manually, and is not reset by a call to destroy().
*/
void setNumRelevantPlanes(const uint8 numRelevantPlanes) { _numRelevantPlanes = numRelevantPlanes; }
/**
* Enables pixel packing, the amount of packing is determined by _numRelevantPlanes
* 1 == decode first plane, pack 8 pixels in 1 byte. This makes _surface->w 1/8th of _header.width
* 2 == decode first 2 planes, pack 4 pixels in 1 byte. This makes _surface->w 1/4th of _header.width
* 4 == decode first 4 planes, pack 2 pixels in 1 byte. This makes _surface->w half of _header.width
* Packed bitmaps won't have a proper surface format since there is no way to tell it to use 1, 2 or 4 bits per pixel
*
* NOTE: this property must be reset manually, and is not reset by a call to destroy().
*/
void setPixelPacking(const bool pixelPacking) { _pixelPacking = pixelPacking; }
private:
Header _header;
Graphics::Surface *_surface;
byte *_palette;
Common::Array<PaletteRange> _paletteRanges;
Type _type;
uint16 _paletteColorCount;
uint8 _numRelevantPlanes;
bool _pixelPacking;
void loadHeader(Common::SeekableReadStream &stream);
void loadPalette(Common::SeekableReadStream &stream, const uint32 size);
void loadPaletteRange(Common::SeekableReadStream &stream, const uint32 size);
void loadBitmap(Common::SeekableReadStream &stream);
void packPixels(byte *scanlines, byte *data, const uint16 scanlinePitch, const uint16 outPitch);
};
/** @} */
} // End of namespace Image
#endif