/**************************************************************************** ** ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the TGA plugin in the Qt ImageFormats module. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and Digia. For licensing terms and ** conditions see http://qt.digia.com/licensing. For further information ** use the contact form at http://qt.digia.com/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 2.1 requirements ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** In addition, as a special exception, Digia gives you certain additional ** rights. These rights are described in the Digia Qt LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qtgafile.h" #include #include #include struct TgaReader { virtual ~TgaReader() {} virtual QRgb operator()(QIODevice *s) const = 0; }; struct Tga16Reader : public TgaReader { ~Tga16Reader() {} QRgb operator()(QIODevice *s) const { char ch1, ch2; if (s->getChar(&ch1) && s->getChar(&ch2)) { quint16 d = (int(ch1) & 0xFF) | ((int(ch2) & 0xFF) << 8); QRgb result = (d & 0x8000) ? 0xFF000000 : 0x00000000; result |= (d & 0x7C00 << 6) | (d & 0x03E0 << 3) | (d & 0x001F); return result; } else { return 0; } } }; struct Tga24Reader : public TgaReader { QRgb operator()(QIODevice *s) const { char r, g, b; if (s->getChar(&b) && s->getChar(&g) && s->getChar(&r)) return qRgb(uchar(r), uchar(g), uchar(b)); else return 0; } }; struct Tga32Reader : public TgaReader { QRgb operator()(QIODevice *s) const { char r, g, b, a; if (s->getChar(&b) && s->getChar(&g) && s->getChar(&r) && s->getChar(&a)) return qRgba(uchar(r), uchar(g), uchar(b), uchar(a)); else return 0; } }; /*! \class QTgaFile \since 4.8 \internal File data container for a TrueVision Graphics format file. Format is as described here: http://local.wasp.uwa.edu.au/~pbourke/dataformats/tga/ http://netghost.narod.ru/gff2/graphics/summary/tga.htm Usage is: \code QTgaFile tga(myFile); QImage tgaImage; if (tga.isValid()) tgaImage = tga.readImage(); \endcode The class is designed to handle sequential and non-sequential sources, so during construction the mHeader is read. Then during the readImage() call the rest of the data is read. After passing myFile to the constructor, if the QIODevice *myFile is read, or has seek() called, the results are undefined - so don't do that. */ /*! Construct a new QTgaFile object getting data from \a device. The object does not take ownership of the \a device, but until the object is destroyed do not do any non-const operations, eg seek or read on the device. */ QTgaFile::QTgaFile(QIODevice *device) : mDevice(device) { ::memset(mHeader, 0, HeaderSize); if (!mDevice->isReadable()) { mErrorMessage = tr("Could not read image data"); return; } if (mDevice->isSequential()) { mErrorMessage = tr("Sequential device (eg socket) for image read not supported"); return; } if (!mDevice->seek(0)) { mErrorMessage = tr("Seek file/device for image read failed"); return; } int bytes = device->read((char*)mHeader, HeaderSize); if (bytes != HeaderSize) { mErrorMessage = tr("Image header read failed"); return; } if (mHeader[ImageType] != 2) { // TODO: should support other image types mErrorMessage = tr("Image type not supported"); return; } int bitsPerPixel = mHeader[PixelDepth]; bool validDepth = (bitsPerPixel == 16 || bitsPerPixel == 24 || bitsPerPixel == 32); if (!validDepth) { mErrorMessage = tr("Image depth not valid"); } int curPos = mDevice->pos(); int fileBytes = mDevice->size(); if (!mDevice->seek(fileBytes - FooterSize)) { mErrorMessage = tr("Could not seek to image read footer"); return; } char footer[FooterSize]; bytes = mDevice->read((char*)footer, FooterSize); if (bytes != FooterSize) { mErrorMessage = tr("Could not read footer"); } if (qstrncmp(&footer[SignatureOffset], "TRUEVISION-XFILE", 16) != 0) { mErrorMessage = tr("Image type (non-TrueVision 2.0) not supported"); } if (!mDevice->seek(curPos)) { mErrorMessage = tr("Could not reset to read data"); } } /*! \internal Destroy the device, recovering any resources. */ QTgaFile::~QTgaFile() { } /*! \internal Reads an image file from the QTgaFile's device, and returns it. This method seeks to the absolute position of the image data in the file, so no assumptions are made about where the devices read pointer is when this method is called. For this reason only random access devices are supported. If the constructor completed successfully, such that isValid() returns true, then this method is likely to succeed, unless the file is somehow corrupted. In the case that the read fails, the QImage returned will be null, such that QImage::isNull() will be true. */ QImage QTgaFile::readImage() { if (!isValid()) return QImage(); int offset = mHeader[IdLength]; // Mostly always zero // Even in TrueColor files a color pallette may be present if (mHeader[ColorMapType] == 1) offset += littleEndianInt(&mHeader[CMapLength]) * littleEndianInt(&mHeader[CMapDepth]); mDevice->seek(HeaderSize + offset); char dummy; for (int i = 0; i < offset; ++i) mDevice->getChar(&dummy); int bitsPerPixel = mHeader[PixelDepth]; int imageWidth = width(); int imageHeight = height(); unsigned char desc = mHeader[ImageDescriptor]; //unsigned char xCorner = desc & 0x10; // 0 = left, 1 = right unsigned char yCorner = desc & 0x20; // 0 = lower, 1 = upper QImage im(imageWidth, imageHeight, QImage::Format_ARGB32); TgaReader *reader = 0; if (bitsPerPixel == 16) reader = new Tga16Reader(); else if (bitsPerPixel == 24) reader = new Tga24Reader(); else if (bitsPerPixel == 32) reader = new Tga32Reader(); TgaReader &read = *reader; // For now only deal with yCorner, since no one uses xCorner == 1 // Also this is upside down, since Qt has the origin flipped if (yCorner) { for (int y = 0; y < imageHeight; ++y) for (int x = 0; x < imageWidth; ++x) im.setPixel(x, y, read(mDevice)); } else { for (int y = imageHeight - 1; y >= 0; --y) for (int x = 0; x < imageWidth; ++x) im.setPixel(x, y, read(mDevice)); } delete reader; // TODO: add processing of TGA extension information - ie TGA 2.0 files return im; }