Photo credit: arstechnica.com

Doom in a PDF: The Unlikely Intersection of Gaming and Document Formats

The world of hacktivism continues to astound, especially when it comes to the enduring legacy of Doom—the pioneering first-person shooter that has found its way onto an eclectic array of devices. From operating systems to unconventional environments, the latest accomplishment is particularly intriguing: Doom now runs within a PDF file, showcasing the versatility of both the game and the technology behind PDF files.

As detailed on the project’s GitHub repository, developer ading2210 highlights Adobe Acrobat’s longstanding support for JavaScript in PDF documents. This functionality, which has been a part of the PDF format for years, allows developers to create interactive content. Despite being less prominent in recent years due to security concerns, JavaScript support is still documented thoroughly in Adobe’s specifications, demonstrating its foundational role in enhancing the PDF format.

Historically, the integration of JavaScript has enabled creative individuals to incorporate simple video games like Breakout and Tetris into PDFs. However, ading2210 pushed the boundaries further by recompiling a custom, streamlined version of Doom‘s open source code, leveraging an older release of Emscripten to produce optimized asm.js code compatible with modern browsers.

This innovative PDF implementation allows users to engage with the game via a text input field, while the game’s output is rendered as ASCII text across 200 separate text fields. Each one represents a horizontal line of the Doom display, effectively simulating a six-color monochrome screen. As a result, players can experience a frame rate of approximately 13 frames per second, which, while not groundbreaking, still emerges as a playable experience—albeit a visually limited one.

Implications for Security and PDF Utility

This project raises important discussions about the implications of scripting capabilities within PDF documents. Given that PDF files are a ubiquitous medium for document sharing, allowing complex scripts could present significant security challenges. However, the potential for creativity and innovation within this framework is also noteworthy, suggesting that PDF files could serve new roles beyond traditional document sharing.

As we witness more experiments like this, the intersection of gaming and document technology may prompt developers and security experts alike to rethink how we utilize various digital formats. For now, the unlikely pairing of Doom and PDFs continues to inspire curiosity about the limits of what can be achieved using established technologies.

Source
arstechnica.com