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image/tga.h

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+/* 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 {
+
+/**
+ * @defgroup image_tga TGA (TARGA) decoder
+ * @ingroup image
+ *
+ * @brief Decoder for TGA images.
+ * @{
+ */
+
+/** TarGa image-decoder
+ * The following variations of TGA are supported:
+ * - Type 1 - Color-mapped images in 16/24/32 bpp with 8 bit indexes
+ * - Type 2 - 16/24/32 bpp Top AND Bottom origined.
+ * - Type 3 - Black/White images, 8bpp.
+ * - Type 9 - RLE-encoded color-mapped images. (8 bit indexes only)
+ * - Type 10 - RLE-encoded TrueColor, 24/32bpp.
+ * - Type 11 - RLE-encoded Black/White, 8bpp.
+ *
+ * No images are returned with a palette, instead they are converted
+ * to 16 bpp for Type 1, or 32 bpp for Black/White-images.
+ */
+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:
+	// https://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