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-rw-r--r--src/gui/util/qktxhandler.cpp199
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diff --git a/src/gui/util/qktxhandler.cpp b/src/gui/util/qktxhandler.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qktxhandler_p.h"
+#include "qtexturefiledata_p.h"
+#include <QtEndian>
+#include <QSize>
+
+//#define KTX_DEBUG
+#ifdef KTX_DEBUG
+#include <QDebug>
+#include <QMetaEnum>
+#include <QOpenGLTexture>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+#define KTX_IDENTIFIER_LENGTH 12
+static const char ktxIdentifier[KTX_IDENTIFIER_LENGTH] = { '\xAB', 'K', 'T', 'X', ' ', '1', '1', '\xBB', '\r', '\n', '\x1A', '\n' };
+static const quint32 platformEndianIdentifier = 0x04030201;
+static const quint32 inversePlatformEndianIdentifier = 0x01020304;
+
+struct KTXHeader {
+ quint8 identifier[KTX_IDENTIFIER_LENGTH]; // Must match ktxIdentifier
+ quint32 endianness; // Either platformEndianIdentifier or inversePlatformEndianIdentifier, other values not allowed.
+ quint32 glType;
+ quint32 glTypeSize;
+ quint32 glFormat;
+ quint32 glInternalFormat;
+ quint32 glBaseInternalFormat;
+ quint32 pixelWidth;
+ quint32 pixelHeight;
+ quint32 pixelDepth;
+ quint32 numberOfArrayElements;
+ quint32 numberOfFaces;
+ quint32 numberOfMipmapLevels;
+ quint32 bytesOfKeyValueData;
+};
+
+static const quint32 headerSize = sizeof(KTXHeader);
+
+// Currently unused, declared for future reference
+struct KTXKeyValuePairItem {
+ quint32 keyAndValueByteSize;
+ /*
+ quint8 keyAndValue[keyAndValueByteSize];
+ quint8 valuePadding[3 - ((keyAndValueByteSize + 3) % 4)];
+ */
+};
+
+struct KTXMipmapLevel {
+ quint32 imageSize;
+ /*
+ for each array_element in numberOfArrayElements*
+ for each face in numberOfFaces
+ for each z_slice in pixelDepth*
+ for each row or row_of_blocks in pixelHeight*
+ for each pixel or block_of_pixels in pixelWidth
+ Byte data[format-specific-number-of-bytes]**
+ end
+ end
+ end
+ Byte cubePadding[0-3]
+ end
+ end
+ quint8 mipPadding[3 - ((imageSize + 3) % 4)]
+ */
+};
+
+bool QKtxHandler::canRead(const QByteArray &suffix, const QByteArray &block)
+{
+ Q_UNUSED(suffix)
+
+ return (qstrncmp(block.constData(), ktxIdentifier, KTX_IDENTIFIER_LENGTH) == 0);
+}
+
+QTextureFileData QKtxHandler::read()
+{
+ if (!device())
+ return QTextureFileData();
+
+ QByteArray buf = device()->readAll();
+ const quint32 dataSize = quint32(buf.size());
+ if (dataSize < headerSize || !canRead(QByteArray(), buf)) {
+ qCDebug(lcQtGuiTextureIO, "Invalid KTX file %s", logName().constData());
+ return QTextureFileData();
+ }
+
+ const KTXHeader *header = reinterpret_cast<const KTXHeader *>(buf.constData());
+ if (!checkHeader(*header)) {
+ qCDebug(lcQtGuiTextureIO, "Unsupported KTX file format in %s", logName().constData());
+ return QTextureFileData();
+ }
+
+ QTextureFileData texData;
+ texData.setData(buf);
+
+ texData.setSize(QSize(decode(header->pixelWidth), decode(header->pixelHeight)));
+ texData.setGLFormat(decode(header->glFormat));
+ texData.setGLInternalFormat(decode(header->glInternalFormat));
+ texData.setGLBaseInternalFormat(decode(header->glBaseInternalFormat));
+
+ texData.setNumLevels(decode(header->numberOfMipmapLevels));
+ quint32 offset = headerSize + decode(header->bytesOfKeyValueData);
+ const int maxLevels = qMin(texData.numLevels(), 32); // Cap iterations in case of corrupt file.
+ for (int i = 0; i < maxLevels; i++) {
+ if (offset + sizeof(KTXMipmapLevel) > dataSize) // Corrupt file; avoid oob read
+ break;
+ const KTXMipmapLevel *level = reinterpret_cast<const KTXMipmapLevel *>(buf.constData() + offset);
+ quint32 levelLen = decode(level->imageSize);
+ texData.setDataOffset(offset + sizeof(KTXMipmapLevel::imageSize), i);
+ texData.setDataLength(levelLen, i);
+ offset += sizeof(KTXMipmapLevel::imageSize) + levelLen + (3 - ((levelLen + 3) % 4));
+ }
+
+ if (!texData.isValid()) {
+ qCDebug(lcQtGuiTextureIO, "Invalid values in header of KTX file %s", logName().constData());
+ return QTextureFileData();
+ }
+
+ texData.setLogName(logName());
+
+#ifdef KTX_DEBUG
+ qDebug() << "KTX file handler read" << texData;
+#endif
+
+ return texData;
+}
+
+bool QKtxHandler::checkHeader(const KTXHeader &header)
+{
+ if (header.endianness != platformEndianIdentifier && header.endianness != inversePlatformEndianIdentifier)
+ return false;
+ inverseEndian = (header.endianness == inversePlatformEndianIdentifier);
+#ifdef KTX_DEBUG
+ QMetaEnum tfme = QMetaEnum::fromType<QOpenGLTexture::TextureFormat>();
+ QMetaEnum ptme = QMetaEnum::fromType<QOpenGLTexture::PixelType>();
+ qDebug("Header of %s:", logName().constData());
+ qDebug(" glType: 0x%x (%s)", decode(header.glType), ptme.valueToKey(decode(header.glType)));
+ qDebug(" glTypeSize: %u", decode(header.glTypeSize));
+ qDebug(" glFormat: 0x%x (%s)", decode(header.glFormat), tfme.valueToKey(decode(header.glFormat)));
+ qDebug(" glInternalFormat: 0x%x (%s)", decode(header.glInternalFormat), tfme.valueToKey(decode(header.glInternalFormat)));
+ qDebug(" glBaseInternalFormat: 0x%x (%s)", decode(header.glBaseInternalFormat), tfme.valueToKey(decode(header.glBaseInternalFormat)));
+ qDebug(" pixelWidth: %u", decode(header.pixelWidth));
+ qDebug(" pixelHeight: %u", decode(header.pixelHeight));
+ qDebug(" pixelDepth: %u", decode(header.pixelDepth));
+ qDebug(" numberOfArrayElements: %u", decode(header.numberOfArrayElements));
+ qDebug(" numberOfFaces: %u", decode(header.numberOfFaces));
+ qDebug(" numberOfMipmapLevels: %u", decode(header.numberOfMipmapLevels));
+ qDebug(" bytesOfKeyValueData: %u", decode(header.bytesOfKeyValueData));
+#endif
+ return ((decode(header.glType) == 0) &&
+ (decode(header.glFormat) == 0) &&
+ (decode(header.pixelDepth) == 0) &&
+ (decode(header.numberOfFaces) == 1));
+}
+
+quint32 QKtxHandler::decode(quint32 val)
+{
+ return inverseEndian ? qbswap<quint32>(val) : val;
+}
+
+QT_END_NAMESPACE
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