Unveiling the Inner Workings of LEGO Island Through Reverse Engineering
In 1997, LEGO Island marked a pivotal moment as the first LEGO video game to break into international markets, selling over one million copies and earning the affection of fans. Now, an enthusiastic team led by MattKC has embarked on a labor of love to reverse engineer the game's codebase, aiming to create a near-perfect replica using custom tools and byte checks.
Despite achieving functional completion, the team acknowledges the impossibility of obtaining a byte-accurate codebase due to challenges with Microsoft's Visual C++ compiler of that era. These "compiler entropy" issues arise from strange behaviors found within the compiler, causing small changes in the code to have seemingly random effects on unrelated sections of the binary. To address this predicament, the team is carefully considering options such as partially reverse engineering Visual C++ or brute forcing the code, but both alternatives would require significant effort and time without providing substantial benefits.
Another intriguing challenge faced by the team centers around the game's graphics. Specifically, DirectX allowed developers to choose between immediate mode and retained mode, with the primary distinction lying in how models and assets were managed. Immediate mode primarily relies on the developer to handle everything aside from rendering, while retained mode uses DirectX as a more comprehensive game engine for model and asset management. Given that retained mode has been deprecated, it's advisable to stick with immediate mode for compatibility on modern Windows PCs. However, this decision raises questions about the best way to move forward when faced with the need for compatible libraries.
With the completion of the reverse engineering phase, the focus now shifts to engineering, addressing longstanding bugs, and eventually porting the game to other platforms. For instance, a bug that forced the game to crash upon exiting and caused data loss was rectified simply by initializing a variable in the game's frontend. However, the timing of this rewrite near the game's release has left some wondering why a modified frontend was required.
The next step is to port the game to other platforms such as Linux, macOS, and potentially mobile devices. This undertaking brings fresh challenges, including the need to rewrite the game for OpenGL and maintaining a balance between historical accuracy and modern development needs.
As the project progresses, engineers will tackle issues like code optimization and improve game compatibility. Potential solutions include emulation using DOSBox or Wine, or recompiling for different platforms using cross-compilation tools. Through dedicated effort and diligent research, the team hopes to deliver a retrograde yet modernized version of the iconic LEGO Island to gaming enthusiasts around the world.
The team, engaged in recreating a near-perfect replica of LEGO Island, recognizes the hurdles presented by the data-and-cloud-computing era's technology, such as the strange behaviors of Microsoft's Visual C++ compiler, which they refer to as "compiler entropy." As they debate solutions to these challenges, they also grapple with the choice of using immediate mode for the game's graphics, given the deprecation of retained mode, and the implications this has for maintaining compatibility on modern platforms.
