tga.h

/* 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/>.
 *
 */

/* Based on code from eos https://github.com/DrMcCoy/xoreos/
 * relicensed under GPLv2+ with permission from DrMcCoy and clone2727
 */

/*
 * TGA decoder used in engines:
 *  - gob
 *  - titanic
 *  - wintermute
 *  - zvision
 */

#ifndef IMAGE_TGA_H
#define IMAGE_TGA_H

#include "graphics/palette.h"
#include "graphics/surface.h"
#include "image/image_decoder.h"

namespace Common {
class SeekableReadStream;
}

namespace Image {

class TGADecoder : public ImageDecoder {
public:
    TGADecoder();
    virtual ~TGADecoder();
    virtual void destroy() override;
    const Graphics::Surface *getSurface() const override { return &_surface; }
    const Graphics::Palette &getPalette() const override { return _colorMap; }
    virtual bool loadStream(Common::SeekableReadStream &stream) override;
private:
    // Format-spec from:
    //http://www.ludorg.net/amnesia/TGA_File_Format_Spec.html
    enum {
        TYPE_CMAP = 1,
        TYPE_TRUECOLOR = 2,
        TYPE_BW = 3,
        TYPE_RLE_CMAP = 9,
        TYPE_RLE_TRUECOLOR = 10,
        TYPE_RLE_BW = 11
    };

    // Color-map:
    bool _colorMapSize;
    Graphics::Palette _colorMap;
    int16 _colorMapOrigin;
    int16 _colorMapLength;
    byte _colorMapEntryLength;

    // Origin may be at the top, or bottom
    bool _originTop;

    Graphics::PixelFormat _format;
    Graphics::Surface _surface;
    // Loading helpers
    bool readHeader(Common::SeekableReadStream &tga, byte &imageType, byte &pixelDepth);
    bool readData(Common::SeekableReadStream &tga, byte imageType, byte pixelDepth);
    bool readDataColorMapped(Common::SeekableReadStream &tga, byte imageType, byte indexDepth);
    bool readDataRLE(Common::SeekableReadStream &tga, byte imageType, byte pixelDepth);
    bool readColorMap(Common::SeekableReadStream &tga, byte imageType, byte pixelDepth);
};
} // End of namespace Image

#endif