Basic FBX parser.

interface/src/avatar/BlendFace.cpp

@@ -11,6 +11,7 @@
 #include "Application.h"
 #include "BlendFace.h"
 #include "Head.h"
+#include "renderer/FBXReader.h"
 
 using namespace fs;
 using namespace std;
@@ -180,7 +181,12 @@ void BlendFace::handleModelDownloadProgress(qint64 bytesReceived, qint64 bytesTo
     _modelReply->deleteLater();
     _modelReply = 0;
     
-    qDebug("Got %d bytes.\n", entirety.size());
+    try {
+        printNode(parseFBX(entirety));
+    
+    } catch (const QString& error) {
+        qDebug() << error << "\n";
+    }
 }
 
 void BlendFace::handleModelReplyError() {

interface/src/renderer/FBXReader.cpp

@@ -0,0 +1,192 @@
+//
+//  FBXReader.cpp
+//  interface
+//
+//  Created by Andrzej Kapolka on 9/18/13.
+//  Copyright (c) 2013 High Fidelity, Inc. All rights reserved.
+//
+
+#include <QBuffer>
+#include <QDataStream>
+#include <QIODevice>
+#include <QtDebug>
+#include <QtEndian>
+
+#include "FBXReader.h"
+
+FBXNode parseFBX(const QByteArray& data) {
+    QBuffer buffer(const_cast<QByteArray*>(&data));
+    buffer.open(QIODevice::ReadOnly);
+    return parseFBX(&buffer);
+}
+
+template<class T> QVariant readArray(QDataStream& in) {
+    quint32 arrayLength;
+    quint32 encoding;
+    quint32 compressedLength;
+    
+    in >> arrayLength;
+    in >> encoding;
+    in >> compressedLength;
+    
+    QVector<T> values;
+    const int DEFLATE_ENCODING = 1;
+    if (encoding == DEFLATE_ENCODING) {
+        // preface encoded data with uncompressed length
+        QByteArray compressed(sizeof(quint32) + compressedLength, 0);
+        *((quint32*)compressed.data()) = qToBigEndian<quint32>(arrayLength * sizeof(T));
+        in.readRawData(compressed.data() + sizeof(quint32), compressedLength);
+        QByteArray uncompressed = qUncompress(compressed);
+        QDataStream uncompressedIn(uncompressed);
+        uncompressedIn.setByteOrder(QDataStream::LittleEndian);
+        for (int i = 0; i < arrayLength; i++) {
+            T value;
+            uncompressedIn >> value;
+            values.append(value);
+        }
+    } else {
+        for (int i = 0; i < arrayLength; i++) {
+            T value;
+            in >> value;
+            values.append(value);
+        }
+    }
+    return QVariant::fromValue(values);
+}
+
+QVariant parseFBXProperty(QDataStream& in) {
+    char ch;
+    in.device()->getChar(&ch);
+    switch (ch) {
+        case 'Y': {
+            qint16 value;
+            in >> value;
+            return QVariant::fromValue(value);   
+        }
+        case 'C': {
+            bool value;
+            in >> value;
+            return QVariant::fromValue(value);
+        }
+        case 'I': {
+            qint32 value;
+            in >> value;
+            return QVariant::fromValue(value);
+        }
+        case 'F': {
+            float value;
+            in >> value;
+            return QVariant::fromValue(value);
+        }
+        case 'D': {
+            double value;
+            in >> value;
+            return QVariant::fromValue(value);
+        }
+        case 'L': {
+            qint64 value;
+            in >> value;
+            return QVariant::fromValue(value);
+        }
+        case 'f': {
+            return readArray<float>(in);
+        }
+        case 'd': {
+            return readArray<double>(in);
+        }
+        case 'l': {
+            return readArray<qint64>(in);
+        }
+        case 'i': {
+            return readArray<qint32>(in);
+        }
+        case 'b': {
+            return readArray<bool>(in);
+        }
+        case 'S':
+        case 'R': {
+            quint32 length;
+            in >> length;
+            return QVariant::fromValue(in.device()->read(length));
+        }
+        default:
+            throw QString("Unknown property type: ") + ch;
+    }
+}
+
+FBXNode parseFBXNode(QDataStream& in) {
+    quint32 endOffset;
+    quint32 propertyCount;
+    quint32 propertyListLength;
+    quint8 nameLength;
+    
+    in >> endOffset;
+    in >> propertyCount;
+    in >> propertyListLength;
+    in >> nameLength;
+    
+    FBXNode node;
+    const int MIN_VALID_OFFSET = 40;
+    if (endOffset < MIN_VALID_OFFSET || nameLength == 0) {
+        // use a null name to indicate a null node
+        return node;
+    } 
+    node.name = in.device()->read(nameLength);
+    
+    for (int i = 0; i < propertyCount; i++) {
+        node.properties.append(parseFBXProperty(in));    
+    }
+    
+    while (endOffset > in.device()->pos()) {
+        FBXNode child = parseFBXNode(in);
+        if (child.name.isNull()) {
+            return node;
+            
+        } else {
+            node.children.append(child);
+        }
+    }
+    
+    return node;
+}
+
+FBXNode parseFBX(QIODevice* device) {
+    QDataStream in(device);
+    in.setByteOrder(QDataStream::LittleEndian);
+    
+    // verify the prolog
+    const QByteArray EXPECTED_PROLOG = "Kaydara FBX Binary  ";
+    if (device->read(EXPECTED_PROLOG.size()) != EXPECTED_PROLOG) {
+        throw QString("Invalid header.");
+    }
+    
+    // skip the rest of the header
+    const int HEADER_SIZE = 27;
+    in.skipRawData(HEADER_SIZE - EXPECTED_PROLOG.size());
+    
+    // parse the top-level node
+    FBXNode top;
+    while (device->bytesAvailable() >= 13) {
+        FBXNode next = parseFBXNode(in);
+        if (next.name.isNull()) {
+            return top;
+            
+        } else {
+            top.children.append(next);
+        }
+    }
+    
+    return top;
+}
+
+void printNode(const FBXNode& node, int indent) {
+    QByteArray spaces(indent, ' ');
+    qDebug("%s%s: ", spaces.data(), node.name.data());
+    foreach (const QVariant& property, node.properties) {
+        qDebug() << property;
+    }
+    qDebug() << "\n";
+    foreach (const FBXNode& child, node.children) {
+        printNode(child, indent + 1);
+    }
+}

interface/src/renderer/FBXReader.h

@@ -0,0 +1,40 @@
+//
+//  FBXReader.h
+//  interface
+//
+//  Created by Andrzej Kapolka on 9/18/13.
+//  Copyright (c) 2013 High Fidelity, Inc. All rights reserved.
+//
+
+#ifndef __interface__FBXReader__
+#define __interface__FBXReader__
+
+#include <QVariant>
+#include <QVector>
+
+class QIODevice;
+
+class FBXNode;
+
+typedef QList<FBXNode> FBXNodeList;
+
+/// A node within an FBX document.
+class FBXNode {
+public:
+    
+    QByteArray name;
+    QVariantList properties;
+    FBXNodeList children;
+};
+
+/// Parses the input from the supplied data as an FBX file.
+/// \exception QString if an error occurs in parsing
+FBXNode parseFBX(const QByteArray& data);
+
+/// Parses the input from the supplied device as an FBX file.
+/// \exception QString if an error occurs in parsing
+FBXNode parseFBX(QIODevice* device);
+
+void printNode(const FBXNode& node, int indent = 0);
+
+#endif /* defined(__interface__FBXReader__) */