1. List of Properties Intrinsic to the .NWD File Format

The .NWD file format is a proprietary binary format developed by Autodesk for Navisworks, primarily used to store 3D model data, review information, and project snapshots in a self-contained manner. Detailed specifications, including byte-level structure and header details, are not publicly available, as Autodesk does not publish low-level documentation. This limits the ability to list exhaustive, technical properties without reverse engineering or access to proprietary tools such as the Navisworks API or third-party SDKs like the Open Design Alliance's BimNv module.

Based on official Autodesk documentation and high-level descriptions from reliable sources, the following properties are intrinsic to the .NWD file format. These represent the core components embedded within the file, ensuring it functions as a standalone document for 3D model review:

• File Header: Includes a magic signature (undocumented but likely a unique identifier for format validation), version number (indicating compatibility with specific Navisworks releases), and optional flags for compression or password protection.
• Geometry Data: Compressed 3D model geometry from appended CAD sources, including vertices, faces, edges, and hierarchical structures for efficient rendering.
• Object Properties: Metadata associated with model elements, such as material attributes, colors, textures, and custom user-defined properties (e.g., BIM data like IDs, categories, and parameters).
• Viewpoints and Camera Settings: Saved camera positions, orientations, and views, including the current view and multiple named viewpoints with associated redlines or tags.
• Review Data: Markups, redlines, comments, and tags for collaborative review.
• Clash Detection Results: Stored clash tests, including detected interferences, groups, and status information.
• Animation and Simulation Data: Sequences for object animations, camera paths, and simulation timelines.
• Timeliner Information: Construction sequencing data, linking model elements to schedules or phases.
• Selection and Search Sets: Predefined groups of model elements for quick selection or querying.
• Environment Settings: Background, lighting, and rendering options for the scene.
• Hyperlinks and Attachments: Embedded links to external resources or documents.
• Security Features: Optional password encryption and digital signatures for file integrity.

These properties make .NWD files compact, secure, and independent of original CAD files, distinguishing them from related formats like .NWF (which references external files) or .NWC (cache files).

2. Two Direct Download Links for .NWD Files

Direct download links for .NWD files are limited in public sources, as most samples are bundled with Autodesk software trials or require registration. The following links were identified:

1. https://forums.autodesk.com/autodesk/attachments/autodesk/navisworks-forum-en/22219/1/gatehouse.nwd (A basic sample model provided by Autodesk on their community forum.)
2. A second unrestricted direct download link could not be located through comprehensive searches of public websites, forums, and repositories. Samples are often available only through Autodesk's Navisworks trial installation or restricted community attachments. For additional samples, it is recommended to download the Navisworks trial from https://www.autodesk.com/products/navisworks/free-trial, which includes example files in the program directory.

3. Ghost Blog Embedded HTML JavaScript for Drag-and-Drop .NWD File Dumping

Given that the .NWD format is proprietary and lacks public specifications for parsing, a complete implementation to extract and dump all intrinsic properties is not feasible without proprietary tools or reverse engineering. The following HTML with embedded JavaScript provides a basic drag-and-drop interface that reads the file as a binary buffer and dumps a hexadecimal representation to the screen. This serves as a starting point for inspection but does not decode specific properties. For full parsing, use the Navisworks API or third-party libraries.

Drag and Drop .NWD File Dumper

This code can be embedded in a Ghost blog post as an HTML block. It displays a hex dump of the first 256 bytes, as a full property extraction is not possible with public knowledge.

4. Python Class for .NWD File Handling

The .NWD format's detailed structure is proprietary, preventing a complete low-level implementation for decoding, reading, writing, and printing properties without Autodesk's API or reverse engineering. The following Python class provides a basic framework for opening the file and printing a hex dump as a placeholder. For actual functionality, integrate with the Navisworks API via COM or use commercial libraries like ODA's.

import binascii
import os

class NWDFileHandler:
    def __init__(self, filepath):
        self.filepath = filepath
        self.data = None

    def open(self):
        if not os.path.exists(self.filepath) or not self.filepath.endswith('.nwd'):
            raise ValueError("Invalid .NWD file path.")
        with open(self.filepath, 'rb') as f:
            self.data = f.read()

    def decode(self):
        # Hypothetical decoding; actual implementation impossible without spec
        print("Decoding not implemented due to proprietary format.")

    def read_properties(self):
        # Placeholder for reading properties
        print("Reading properties not implemented due to proprietary format.")

    def write_properties(self, properties):
        # Placeholder for writing
        print("Writing not implemented due to proprietary format.")

    def print_properties(self):
        if self.data is None:
            raise ValueError("File not opened.")
        # Print hex dump as placeholder
        hex_dump = binascii.hexlify(self.data[:256]).decode('utf-8')
        print("Hex dump of first 256 bytes (properties not decodable):")
        print(hex_dump)
        print("\nNote: Full property printing requires proprietary specifications.")

# Example usage:
# handler = NWDFileHandler('path/to/file.nwd')
# handler.open()
# handler.print_properties()

5. Java Class for .NWD File Handling

Similarly, due to the proprietary nature of the format, a complete Java class for low-level operations is not possible. The following provides a basic structure with a hex dump placeholder.

import java.io.*;
import java.nio.file.Files;
import java.nio.file.Paths;

public class NWDFileHandler {
    private String filepath;
    private byte[] data;

    public NWDFileHandler(String filepath) {
        this.filepath = filepath;
    }

    public void open() throws IOException {
        if (!filepath.endsWith(".nwd")) {
            throw new IllegalArgumentException("Invalid .NWD file.");
        }
        data = Files.readAllBytes(Paths.get(filepath));
    }

    public void decode() {
        System.out.println("Decoding not implemented due to proprietary format.");
    }

    public void readProperties() {
        System.out.println("Reading properties not implemented due to proprietary format.");
    }

    public void writeProperties(Object properties) {
        System.out.println("Writing not implemented due to proprietary format.");
    }

    public void printProperties() {
        if (data == null) {
            throw new IllegalStateException("File not opened.");
        }
        // Hex dump placeholder
        StringBuilder hexDump = new StringBuilder("Hex dump of first 256 bytes:\n");
        for (int i = 0; i < Math.min(256, data.length); i++) {
            hexDump.append(String.format("%02X ", data[i]));
            if ((i + 1) % 16 == 0) hexDump.append("\n");
        }
        System.out.println(hexDump);
        System.out.println("\nNote: Full property printing requires proprietary specifications.");
    }

    // Example usage:
    // public static void main(String[] args) throws IOException {
    //     NWDFileHandler handler = new NWDFileHandler("path/to/file.nwd");
    //     handler.open();
    //     handler.printProperties();
    // }
}

6. JavaScript Class for .NWD File Handling

For JavaScript (Node.js context), the same limitations apply. The class below uses the 'fs' module for file operations and provides a hex dump.

const fs = require('fs');

class NWDFileHandler {
    constructor(filepath) {
        this.filepath = filepath;
        this.data = null;
    }

    open() {
        if (!this.filepath.endsWith('.nwd')) {
            throw new Error('Invalid .NWD file.');
        }
        this.data = fs.readFileSync(this.filepath);
    }

    decode() {
        console.log('Decoding not implemented due to proprietary format.');
    }

    readProperties() {
        console.log('Reading properties not implemented due to proprietary format.');
    }

    writeProperties(properties) {
        console.log('Writing not implemented due to proprietary format.');
    }

    printProperties() {
        if (!this.data) {
            throw new Error('File not opened.');
        }
        let hexDump = 'Hex dump of first 256 bytes:\n';
        for (let i = 0; i < Math.min(256, this.data.length); i++) {
            hexDump += this.data[i].toString(16).padStart(2, '0').toUpperCase() + ' ';
            if ((i + 1) % 16 === 0) hexDump += '\n';
        }
        console.log(hexDump);
        console.log('\nNote: Full property printing requires proprietary specifications.');
    }
}

// Example usage:
// const handler = new NWDFileHandler('path/to/file.nwd');
// handler.open();
// handler.printProperties();

7. C Class for .NWD File Handling

In C, the limitations remain. The following struct-based implementation opens the file and prints a hex dump as a placeholder. Compile with a standard C compiler.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct {
    char* filepath;
    unsigned char* data;
    size_t size;
} NWDFileHandler;

NWDFileHandler* createNWDHandler(const char* filepath) {
    NWDFileHandler* handler = (NWDFileHandler*)malloc(sizeof(NWDFileHandler));
    handler->filepath = strdup(filepath);
    handler->data = NULL;
    handler->size = 0;
    return handler;
}

void openFile(NWDFileHandler* handler) {
    if (strstr(handler->filepath, ".nwd") == NULL) {
        fprintf(stderr, "Invalid .NWD file.\n");
        return;
    }
    FILE* file = fopen(handler->filepath, "rb");
    if (!file) {
        fprintf(stderr, "Could not open file.\n");
        return;
    }
    fseek(file, 0, SEEK_END);
    handler->size = ftell(file);
    fseek(file, 0, SEEK_SET);
    handler->data = (unsigned char*)malloc(handler->size);
    fread(handler->data, 1, handler->size, file);
    fclose(file);
}

void decode(NWDFileHandler* handler) {
    printf("Decoding not implemented due to proprietary format.\n");
}

void readProperties(NWDFileHandler* handler) {
    printf("Reading properties not implemented due to proprietary format.\n");
}

void writeProperties(NWDFileHandler* handler) {
    printf("Writing not implemented due to proprietary format.\n");
}

void printProperties(NWDFileHandler* handler) {
    if (!handler->data) {
        fprintf(stderr, "File not opened.\n");
        return;
    }
    printf("Hex dump of first 256 bytes:\n");
    for (size_t i = 0; i < 256 && i < handler->size; i++) {
        printf("%02X ", handler->data[i]);
        if ((i + 1) % 16 == 0) printf("\n");
    }
    printf("\nNote: Full property printing requires proprietary specifications.\n");
}

void destroyNWDHandler(NWDFileHandler* handler) {
    free(handler->data);
    free(handler->filepath);
    free(handler);
}

// Example usage:
// int main() {
//     NWDFileHandler* handler = createNWDHandler("path/to/file.nwd");
//     openFile(handler);
//     printProperties(handler);
//     destroyNWDHandler(handler);
//     return 0;
// }