vmap/plugins/image/tga.cpp

/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant 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.

   GtkRadiant 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 GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "tga.h"

#include "ifilesystem.h"
#include "iarchive.h"
#include "idatastream.h"

typedef unsigned char byte;

#include <stdlib.h>

#include "generic/bitfield.h"
#include "imagelib.h"
#include "bytestreamutils.h"

// represents x,y origin of tga image being decoded
class Flip00 {}; // no flip
class Flip01 {}; // vertical flip only
class Flip10 {}; // horizontal flip only
class Flip11 {}; // both

template<typename PixelDecoder>
void image_decode(PointerInputStream &istream, PixelDecoder &decode, RGBAImage &image, const Flip00 &)
{
	RGBAPixel *end = image.pixels + (image.height * image.width);
	for (RGBAPixel *row = end; row != image.pixels; row -= image.width) {
		for (RGBAPixel *pixel = row - image.width; pixel != row; ++pixel) {
			decode(istream, *pixel);
		}
	}
}

template<typename PixelDecoder>
void image_decode(PointerInputStream &istream, PixelDecoder &decode, RGBAImage &image, const Flip01 &)
{
	RGBAPixel *end = image.pixels + (image.height * image.width);
	for (RGBAPixel *row = image.pixels; row != end; row += image.width) {
		for (RGBAPixel *pixel = row; pixel != row + image.width; ++pixel) {
			decode(istream, *pixel);
		}
	}
}

template<typename PixelDecoder>
void image_decode(PointerInputStream &istream, PixelDecoder &decode, RGBAImage &image, const Flip10 &)
{
	RGBAPixel *end = image.pixels + (image.height * image.width);
	for (RGBAPixel *row = end; row != image.pixels; row -= image.width) {
		for (RGBAPixel *pixel = row; pixel != row - image.width;) {
			decode(istream, *--pixel);
		}
	}
}

template<typename PixelDecoder>
void image_decode(PointerInputStream &istream, PixelDecoder &decode, RGBAImage &image, const Flip11 &)
{
	RGBAPixel *end = image.pixels + (image.height * image.width);
	for (RGBAPixel *row = image.pixels; row != end; row += image.width) {
		for (RGBAPixel *pixel = row + image.width; pixel != row;) {
			decode(istream, *--pixel);
		}
	}
}

inline void istream_read_gray(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream.read(&pixel.blue, 1);
	pixel.red = pixel.green = pixel.blue;
	pixel.alpha = 0xff;
}

inline void istream_read_rgb(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream.read(&pixel.blue, 1);
	istream.read(&pixel.green, 1);
	istream.read(&pixel.red, 1);
	pixel.alpha = 0xff;
}

inline void istream_read_rgba(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream.read(&pixel.blue, 1);
	istream.read(&pixel.green, 1);
	istream.read(&pixel.red, 1);
	istream.read(&pixel.alpha, 1);
}

class TargaDecodeGrayPixel {
public:
void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream_read_gray(istream, pixel);
}
};

template<typename Flip>
void targa_decode_grayscale(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeGrayPixel decode;
	image_decode(istream, decode, image, flip);
}

class TargaDecodeRGBPixel {
public:
void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream_read_rgb(istream, pixel);
}
};

template<typename Flip>
void targa_decode_rgb(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeRGBPixel decode;
	image_decode(istream, decode, image, flip);
}

class TargaDecodeRGBAPixel {
public:
void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	istream_read_rgba(istream, pixel);
}
};

template<typename Flip>
void targa_decode_rgba(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeRGBAPixel decode;
	image_decode(istream, decode, image, flip);
}

typedef byte TargaPacket;
typedef byte TargaPacketSize;

inline void targa_packet_read_istream(TargaPacket &packet, PointerInputStream &istream)
{
	istream.read(&packet, 1);
}

inline bool targa_packet_is_rle(const TargaPacket &packet)
{
	return (packet & 0x80) != 0;
}

inline TargaPacketSize targa_packet_size(const TargaPacket &packet)
{
	return 1 + (packet & 0x7f);
}


class TargaDecodeGrayPixelRLE {
TargaPacketSize m_packetSize;
RGBAPixel m_pixel;
TargaPacket m_packet;
public:
TargaDecodeGrayPixelRLE() : m_packetSize(0)
{
}

void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	if (m_packetSize == 0) {
		targa_packet_read_istream(m_packet, istream);
		m_packetSize = targa_packet_size(m_packet);

		if (targa_packet_is_rle(m_packet)) {
			istream_read_gray(istream, m_pixel);
		}
	}

	if (targa_packet_is_rle(m_packet)) {
		pixel = m_pixel;
	} else {
		istream_read_gray(istream, pixel);
	}

	--m_packetSize;
}
};

template<typename Flip>
void targa_decode_rle_grayscale(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeGrayPixelRLE decode;
	image_decode(istream, decode, image, flip);
}

class TargaDecodeRGBPixelRLE {
TargaPacketSize m_packetSize;
RGBAPixel m_pixel;
TargaPacket m_packet;
public:
TargaDecodeRGBPixelRLE() : m_packetSize(0)
{
}

void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	if (m_packetSize == 0) {
		targa_packet_read_istream(m_packet, istream);
		m_packetSize = targa_packet_size(m_packet);

		if (targa_packet_is_rle(m_packet)) {
			istream_read_rgb(istream, m_pixel);
		}
	}

	if (targa_packet_is_rle(m_packet)) {
		pixel = m_pixel;
	} else {
		istream_read_rgb(istream, pixel);
	}

	--m_packetSize;
}
};

template<typename Flip>
void targa_decode_rle_rgb(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeRGBPixelRLE decode;
	image_decode(istream, decode, image, flip);
}

class TargaDecodeRGBAPixelRLE {
TargaPacketSize m_packetSize;
RGBAPixel m_pixel;
TargaPacket m_packet;
public:
TargaDecodeRGBAPixelRLE() : m_packetSize(0)
{
}

void operator()(PointerInputStream &istream, RGBAPixel &pixel)
{
	if (m_packetSize == 0) {
		targa_packet_read_istream(m_packet, istream);
		m_packetSize = targa_packet_size(m_packet);

		if (targa_packet_is_rle(m_packet)) {
			istream_read_rgba(istream, m_pixel);
		}
	}

	if (targa_packet_is_rle(m_packet)) {
		pixel = m_pixel;
	} else {
		istream_read_rgba(istream, pixel);
	}

	--m_packetSize;
}
};

template<typename Flip>
void targa_decode_rle_rgba(PointerInputStream &istream, RGBAImage &image, const Flip &flip)
{
	TargaDecodeRGBAPixelRLE decode;
	image_decode(istream, decode, image, flip);
}

struct TargaHeader {
	unsigned char id_length, colormap_type, image_type;
	unsigned short colormap_index, colormap_length;
	unsigned char colormap_size;
	unsigned short x_origin, y_origin, width, height;
	unsigned char pixel_size, attributes;
};

inline void targa_header_read_istream(TargaHeader &targa_header, PointerInputStream &istream)
{
	targa_header.id_length = istream_read_byte(istream);
	targa_header.colormap_type = istream_read_byte(istream);
	targa_header.image_type = istream_read_byte(istream);

	targa_header.colormap_index = istream_read_int16_le(istream);
	targa_header.colormap_length = istream_read_int16_le(istream);
	targa_header.colormap_size = istream_read_byte(istream);
	targa_header.x_origin = istream_read_int16_le(istream);
	targa_header.y_origin = istream_read_int16_le(istream);
	targa_header.width = istream_read_int16_le(istream);
	targa_header.height = istream_read_int16_le(istream);
	targa_header.pixel_size = istream_read_byte(istream);
	targa_header.attributes = istream_read_byte(istream);

	if (targa_header.id_length != 0) {
		istream.seek(targa_header.id_length); // skip TARGA image comment
	}
}

template<typename Type>
class ScopeDelete {
Type *m_value;

ScopeDelete(const ScopeDelete &);

ScopeDelete &operator=(const ScopeDelete &);

public:
ScopeDelete(Type *value) : m_value(value)
{
}

~ScopeDelete()
{
	delete m_value;
}

Type *get_pointer() const
{
	return m_value;
}
};

template<typename Flip>
Image *Targa_decodeImageData(const TargaHeader &targa_header, PointerInputStream &istream, const Flip &flip)
{
	RGBAImage *image = new RGBAImage(targa_header.width, targa_header.height);

	if (targa_header.image_type == 2 || targa_header.image_type == 3) {
		switch (targa_header.pixel_size) {
		case 8:
			targa_decode_grayscale(istream, *image, flip);
			break;
		case 24:
			targa_decode_rgb(istream, *image, flip);
			break;
		case 32:
			targa_decode_rgba(istream, *image, flip);
			break;
		default:
			globalErrorStream() << "LoadTGA: illegal pixel_size '" << targa_header.pixel_size << "'\n";
			image->release();
			return 0;
		}
	} else if (targa_header.image_type == 10 || targa_header.image_type == 11) {
		switch (targa_header.pixel_size) {
		case 8:
			targa_decode_rle_grayscale(istream, *image, flip);
			break;
		case 24:
			targa_decode_rle_rgb(istream, *image, flip);
			break;
		case 32:
			targa_decode_rle_rgba(istream, *image, flip);
			break;
		default:
			globalErrorStream() << "LoadTGA: illegal pixel_size '" << targa_header.pixel_size << "'\n";
			image->release();
			return 0;
		}
	}

	return image;
}

const unsigned int TGA_FLIP_HORIZONTAL = 0x10;
const unsigned int TGA_FLIP_VERTICAL = 0x20;

Image *LoadTGABuff(const byte *buffer)
{
	PointerInputStream istream(buffer);
	TargaHeader targa_header;

	targa_header_read_istream(targa_header, istream);

	if (targa_header.image_type != 2 && targa_header.image_type != 10 && targa_header.image_type != 3 &&
	    targa_header.image_type != 11) {
		globalErrorStream() << "LoadTGA: TGA type " << targa_header.image_type << " not supported\n";
		globalErrorStream() << "LoadTGA: Only type 2 (RGB), 3 (gray), 10 (RGB), and 11 (gray) TGA images supported\n";
		return 0;
	}

	if (targa_header.colormap_type != 0) {
		globalErrorStream() << "LoadTGA: colormaps not supported\n";
		return 0;
	}

	if (((targa_header.image_type == 2 || targa_header.image_type == 10) && targa_header.pixel_size != 32 &&
	     targa_header.pixel_size != 24) ||
	    ((targa_header.image_type == 3 || targa_header.image_type == 11) && targa_header.pixel_size != 8)) {
		globalErrorStream() << "LoadTGA: Only 32, 24 or 8 bit images supported\n";
		return 0;
	}

	if (!bitfield_enabled(targa_header.attributes, TGA_FLIP_HORIZONTAL)
	    && !bitfield_enabled(targa_header.attributes, TGA_FLIP_VERTICAL)) {
		return Targa_decodeImageData(targa_header, istream, Flip00());
	}
	if (!bitfield_enabled(targa_header.attributes, TGA_FLIP_HORIZONTAL)
	    && bitfield_enabled(targa_header.attributes, TGA_FLIP_VERTICAL)) {
		return Targa_decodeImageData(targa_header, istream, Flip01());
	}
	if (bitfield_enabled(targa_header.attributes, TGA_FLIP_HORIZONTAL)
	    && !bitfield_enabled(targa_header.attributes, TGA_FLIP_VERTICAL)) {
		return Targa_decodeImageData(targa_header, istream, Flip10());
	}
	if (bitfield_enabled(targa_header.attributes, TGA_FLIP_HORIZONTAL)
	    && bitfield_enabled(targa_header.attributes, TGA_FLIP_VERTICAL)) {
		return Targa_decodeImageData(targa_header, istream, Flip11());
	}

	// unreachable
	return 0;
}

Image *LoadTGA(ArchiveFile &file)
{
	ScopedArchiveBuffer buffer(file);
	return LoadTGABuff(buffer.buffer);
}