Software Engineering Daily: Grand Theft Auto III on the Dreamcast with Falco Girgis and Stef Kornilios Mitsis Poiitidis

Release Date: May 8, 2025

Introduction

In this captivating episode of Software Engineering Daily, the host delves into the ambitious project of porting the iconic Grand Theft Auto III (GTA III) to the Sega Dreamcast console. Joining the discussion are Falco Girgis and Stef Cornelio Smitsas Poitidis, the brilliant minds behind this intricate endeavor. The conversation navigates through the technical challenges, innovative solutions, and the passion driving this unique porting project.

Background of the Developers

Stef Cornelio Smitsas Poitidis introduced his journey into Dreamcast development:

"[...] I have implemented the Dreamcast in software that started as a childhood project. Actually, it's been ongoing for 20 years [...]" (01:53)

Transitioning from emulator development to porting, Stef emphasizes his shift in focus to contribute directly to making GTA III run on the Dreamcast hardware.

Falco Girgis shared his early fascination with Dreamcast game development:

"I actually taught myself C and C++ at age 14 because I specifically wanted to make Dreamcast games when I was a kid." (02:28)

Falco's long-standing commitment is evident as he currently maintains the Callistios SDK, a cornerstone for Dreamcast development.

Understanding Grand Theft Auto III and Its Significance

Kevin Ball sets the stage by highlighting GTA III's monumental impact on gaming and open-world design:

"Grand Theft Auto III is a 2001 open world action-adventure game developed by Rockstar Games, and it had a profound impact on both gaming and popular culture." (00:00)

The game's success not only solidified video games as a dominant entertainment medium but also pushed technological boundaries, making the porting project both a tribute and a technical challenge.

Challenges in Porting GTA III to Dreamcast

Porting GTA III to the Dreamcast was no small feat, primarily due to stark hardware limitations:

• Memory Constraints: The Dreamcast operates with 16 MB of main memory and 8 MB of video memory, significantly less than the original PC and PlayStation 2 versions. Stef elaborates:

  "We have 16 megabytes of main memory for everything and then 8 megabytes for video. [...] That's like very small specs compared to even then PC standards." (04:36)

• Rendering Engine Adaptation: The original game engine supported platforms like OpenGL and Direct3D, necessitating a new renderer tailored for the Dreamcast's hardware specifications.

• Physics Engine Optimization: Falco discusses the complexities of adapting the physics engine without the Dreamcast's vector co-processor:

  "We don't have that on the Dreamcast, no vector COProcessor. But we do have some pretty cool instructions that like a very fast sine cosine approximation..." (07:15)

Technical Innovations and Solutions

The team employed several ingenious techniques to overcome hardware limitations:

• Custom Renderer Development: Stef and Falco built a new renderer compatible with Dreamcast's unique graphics pipeline, handling opaque, translucent, and alpha-tested geometry separately to fit the console's requirements.

• Cache Management Enhancements: By splitting the Dreamcast's cache and manually controlling data flow, they optimized vertex processing, a breakthrough that Falco finds particularly impressive:

  "We have a mode where he split the cache in half. [...] It was pretty mind-blowing." (19:38)

• Physics Engine Adjustments: To maintain a stable physics system, Falco utilized the Dreamcast's fast sine and cosine approximation instructions, ensuring efficient vector calculations without compromising gameplay.

• Toolchain and Emulation Support: Stef maintained a customized Dreamcast emulator, enabling efficient debugging and integration with modern development tools like Valgrind and Address Sanitizer:

  "We can use tools like Valgrind or Address Sanitizer. [...] This has really helped us." (23:01)

Project Status and Future Endeavors

As of the episode's release, the GTA III Dreamcast port has transitioned from alpha to a fully playable state, with only minor bugs remaining. The team's immediate focus includes addressing memory fragmentation issues to ensure extended playability without crashes.

Looking ahead, the developers contemplate porting Vice City, another popular title in the GTA series, leveraging the groundwork laid by the GTA III project.

"It's very straightforward to get to the menus. And then it was just we needed a new renderer for the game engine because it doesn't support." (10:41)

Community Involvement and Open Source Contributions

Both Falco and Stef emphasize the importance of community collaboration. They invite enthusiasts to contribute via their Dreamcast Wiki, Discord server, and GitHub repositories.

Falco encourages newcomers:

"Start off, we have a wiki, Dreamcast wiki. [...] And it's the ultimate getting started." (43:58)

Stef provides resources for those interested in replicating the port:

"For GTA 3 specifically we have some basic instructions, but you have to do the repack yourself. [...] And from there, you have to run some commands, download the Dreamcast SDK, run some commands and it will bake everything for you." (45:28)

Notable Quotes

• Stef on Memory Constraints:

  "We have 16 megabytes of main memory for everything and then 8 megabytes for video. [...] That's like very small specs compared to even then PC standards." (04:36)

• Falco on Physics Engine Optimization:

  "We don't have that on the Dreamcast, no vector co-processor. But we do have some pretty cool instructions..." (07:15)

• Stef on Renderer Development:

  "The game engine, of course, it only supports OpenGL Direct 3D and it has some beats for Xbox and PS2, but only some bits. And we had to bring in support for all of the custom texture formats that the graphics card support for the Dreamcast..." (10:41)

• Falco on Cache Management:

  "You have to capture the pipeline state... and then he placed them into standard vectors and then he could iterate over them later when he needed to." (16:17)

• Stef on Profiler Tools:

  "We have a profiler that is passed down from some other developer to me and I modified it..." (35:20)

Conclusion

The GTA III Dreamcast port project stands as a testament to the ingenuity and dedication of its developers. By meticulously navigating hardware limitations and leveraging community-driven tools, Falco Girgis and Stef Cornelio Smitsas Poitidis have breathed new life into a classic game on beloved retro hardware. Their work not only preserves gaming history but also inspires future endeavors in niche game development communities.

For enthusiasts eager to join or support the project, resources and collaboration opportunities are readily available through their official platforms.

Interested in diving deeper or contributing to the project? Visit dca3.net, join the Discord community, or explore the repositories on GitHub under the Callistios organization.