Task 158: .DWF File Format

File Format Specifications for the .DWF File Format

The .DWF (Design Web Format) file format, developed by Autodesk, is a binary and ASCII-based format intended for the efficient distribution and viewing of 2D and 3D design data. It is structured into three primary sections: a file identification header, a file data block containing opcode-operand pairs, and a file termination trailer. The format supports little-endian binary operands, logical coordinates with 31-bit precision, and mechanisms for skipping unrecognized opcodes. It allows for both human-readable ASCII elements and binary efficiency, with optional compression through relative coordinates. The specification detailed here is based on the WHIP! format, which underpins classic .DWF files (distinct from the XML-based DWFx variant).

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

The properties intrinsic to the .DWF file format include the file header version and various metadata and configuration elements encoded primarily as extended ASCII opcodes within the file data block. These opcodes represent key attributes such as authorship, timestamps, drawing settings, and other file-specific information. Below is a comprehensive list derived from the format specification:

Additionally, the file header includes:

• Version: A 5-byte string (e.g., "00.30") indicating major and minor revisions.

Note: Drawing commands such as Bezier, ContourSet, Gouraud, Image, and EmbedFile/EmbedRef are part of the format but are considered operational rather than intrinsic properties.

2. Two Direct Download Links for .DWF Files

• https://www.4crawler.com/Developer/DWF/a-rcp1.dwf
• https://www.4crawler.com/Developer/DWF/home1.dwf

3. Ghost Blog Embedded HTML/JavaScript for Drag-and-Drop .DWF File Processing

The following is an embeddable HTML snippet with JavaScript suitable for integration into a Ghost blog post. It provides a drag-and-drop interface for uploading a .DWF file, parses the file to extract the listed properties, and displays them on the screen. The parser focuses on extended ASCII opcodes, assuming primarily ASCII content for simplicity; binary sections are skipped.

4. Python Class for .DWF File Handling

The following Python class can open a .DWF file, decode and read the properties, print them to the console, and write a new .DWF file with specified properties.

import re

class DwfHandler:
    def __init__(self):
        self.properties = {}
        self.version = "00.30"  # Default version

    def read(self, filename):
        with open(filename, 'r', encoding='utf-8', errors='ignore') as f:
            content = f.read()
        # Extract version
        version_match = re.match(r'^\(DWF V(\d{2}\.\d{2})\)', content)
        if version_match:
            self.version = version_match.group(1)
        # Extract properties
        opcode_regex = re.compile(r'\((Author|Background|Bounds|Clip|Color|ColorMap|Comment|Created|Creator|Description|DrawingInfo|Layer|LineCap|LineJoin|LinePattern|LineWeight|Modified|Projection|Scale|SourceCreated|SourceFilename|SourceModified|URL|View)(.*?)\)', re.DOTALL)
        for match in opcode_regex.finditer(content):
            token = match.group(1)
            operands = match.group(2).strip()
            self.properties[token] = operands
        self.print_properties()

    def print_properties(self):
        print(f"Version: {self.version}")
        for key, value in self.properties.items():
            print(f"{key}: {value}")

    def write(self, filename, properties=None):
        if properties:
            self.properties.update(properties)
        with open(filename, 'w', encoding='utf-8') as f:
            f.write(f"(DWF V{self.version})\n")
            for key, value in self.properties.items():
                f.write(f"({key} {value})\n")
            f.write("(EndOfDWF)\n")

# Example usage:
# handler = DwfHandler()
# handler.read('sample.dwf')
# handler.write('output.dwf', {'Author': 'John Doe'})

5. Java Class for .DWF File Handling

The following Java class can open a .DWF file, decode and read the properties, print them to the console, and write a new .DWF file with specified properties.

import java.io.*;
import java.util.*;
import java.util.regex.*;

public class DwfHandler {
    private String version = "00.30";
    private Map<String, String> properties = new HashMap<>();

    public void read(String filename) throws IOException {
        StringBuilder content = new StringBuilder();
        try (BufferedReader reader = new BufferedReader(new FileReader(filename))) {
            String line;
            while ((line = reader.readLine()) != null) {
                content.append(line).append("\n");
            }
        }
        // Extract version
        Pattern versionPattern = Pattern.compile("^\\(DWF V(\\d{2}\\.\\d{2})\\)");
        Matcher versionMatcher = versionPattern.matcher(content);
        if (versionMatcher.find()) {
            version = versionMatcher.group(1);
        }
        // Extract properties
        Pattern opcodePattern = Pattern.compile("\\((Author|Background|Bounds|Clip|Color|ColorMap|Comment|Created|Creator|Description|DrawingInfo|Layer|LineCap|LineJoin|LinePattern|LineWeight|Modified|Projection|Scale|SourceCreated|SourceFilename|SourceModified|URL|View)(.*?)\\)", Pattern.DOTALL);
        Matcher matcher = opcodePattern.matcher(content);
        while (matcher.find()) {
            String token = matcher.group(1);
            String operands = matcher.group(2).trim();
            properties.put(token, operands);
        }
        printProperties();
    }

    public void printProperties() {
        System.out.println("Version: " + version);
        for (Map.Entry<String, String> entry : properties.entrySet()) {
            System.out.println(entry.getKey() + ": " + entry.getValue());
        }
    }

    public void write(String filename, Map<String, String> newProperties) throws IOException {
        if (newProperties != null) {
            properties.putAll(newProperties);
        }
        try (BufferedWriter writer = new BufferedWriter(new FileWriter(filename))) {
            writer.write("(DWF V" + version + ")\n");
            for (Map.Entry<String, String> entry : properties.entrySet()) {
                writer.write("(" + entry.getKey() + " " + entry.getValue() + ")\n");
            }
            writer.write("(EndOfDWF)\n");
        }
    }

    // Example usage:
    // public static void main(String[] args) throws IOException {
    //     DwfHandler handler = new DwfHandler();
    //     handler.read("sample.dwf");
    //     Map<String, String> props = new HashMap<>();
    //     props.put("Author", "John Doe");
    //     handler.write("output.dwf", props);
    // }
}

6. JavaScript Class for .DWF File Handling

The following JavaScript class can open a .DWF file (using Node.js for file I/O), decode and read the properties, print them to the console, and write a new .DWF file with specified properties.

const fs = require('fs');

class DwfHandler {
    constructor() {
        this.version = '00.30';
        this.properties = {};
    }

    read(filename) {
        const content = fs.readFileSync(filename, 'utf8');
        // Extract version
        const versionMatch = content.match(/^\(DWF V(\d{2}\.\d{2})\)/);
        if (versionMatch) {
            this.version = versionMatch[1];
        }
        // Extract properties
        const opcodeRegex = /\((Author|Background|Bounds|Clip|Color|ColorMap|Comment|Created|Creator|Description|DrawingInfo|Layer|LineCap|LineJoin|LinePattern|LineWeight|Modified|Projection|Scale|SourceCreated|SourceFilename|SourceModified|URL|View)(.*?)\)/gs;
        let match;
        while ((match = opcodeRegex.exec(content)) !== null) {
            const token = match[1];
            const operands = match[2].trim();
            this.properties[token] = operands;
        }
        this.printProperties();
    }

    printProperties() {
        console.log(`Version: ${this.version}`);
        for (const [key, value] of Object.entries(this.properties)) {
            console.log(`${key}: ${value}`);
        }
    }

    write(filename, newProperties = {}) {
        Object.assign(this.properties, newProperties);
        let output = `(DWF V${this.version})\n`;
        for (const [key, value] of Object.entries(this.properties)) {
            output += `(${key} ${value})\n`;
        }
        output += '(EndOfDWF)\n';
        fs.writeFileSync(filename, output, 'utf8');
    }
}

// Example usage:
// const handler = new DwfHandler();
// handler.read('sample.dwf');
// handler.write('output.dwf', { Author: 'John Doe' });

7. C Class (Using C++ for Object-Oriented Structure) for .DWF File Handling

The following C++ class can open a .DWF file, decode and read the properties, print them to the console, and write a new .DWF file with specified properties. It uses standard libraries for file handling and regular expressions.

#include <iostream>
#include <fstream>
#include <string>
#include <map>
#include <regex>

class DwfHandler {
private:
    std::string version = "00.30";
    std::map<std::string, std::string> properties;

public:
    void read(const std::string& filename) {
        std::ifstream file(filename);
        std::string content((std::istreambuf_iterator<char>(file)), std::istreambuf_iterator<char>());
        file.close();
        // Extract version
        std::regex versionRegex(R"(^\(DWF V(\d{2}\.\d{2})\))");
        std::smatch versionMatch;
        if (std::regex_search(content, versionMatch, versionRegex)) {
            version = versionMatch[1];
        }
        // Extract properties
        std::regex opcodeRegex(R"(\((Author|Background|Bounds|Clip|Color|ColorMap|Comment|Created|Creator|Description|DrawingInfo|Layer|LineCap|LineJoin|LinePattern|LineWeight|Modified|Projection|Scale|SourceCreated|SourceFilename|SourceModified|URL|View)(.*?)\))");
        std::sregex_iterator iter(content.begin(), content.end(), opcodeRegex);
        std::sregex_iterator end;
        for (; iter != end; ++iter) {
            std::string token = (*iter)[1];
            std::string operands = (*iter)[2];
            // Trim operands
            operands.erase(0, operands.find_first_not_of(" \t\n\r\f\v"));
            operands.erase(operands.find_last_not_of(" \t\n\r\f\v") + 1);
            properties[token] = operands;
        }
        printProperties();
    }

    void printProperties() const {
        std::cout << "Version: " << version << std::endl;
        for (const auto& pair : properties) {
            std::cout << pair.first << ": " << pair.second << std::endl;
        }
    }

    void write(const std::string& filename, const std::map<std::string, std::string>& newProperties) {
        for (const auto& pair : newProperties) {
            properties[pair.first] = pair.second;
        }
        std::ofstream file(filename);
        file << "(DWF V" << version << ")\n";
        for (const auto& pair : properties) {
            file << "(" << pair.first << " " << pair.second << ")\n";
        }
        file << "(EndOfDWF)\n";
        file.close();
    }
};

// Example usage:
// int main() {
//     DwfHandler handler;
//     handler.read("sample.dwf");
//     std::map<std::string, std::string> props = {{"Author", "John Doe"}};
//     handler.write("output.dwf", props);
//     return 0;
// }