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);
}