The Many Many Missed Opportunities of Sonic 06

Sonic 06 has been plagued by many missed opportunities due to extensive cut content. During the development of Marathon Recompiled, the team has uncovered a significant amount of missing features, including advanced rendering capabilities in various areas of the game. For instance, Crisis City boasts reflections, particle effects, and dramatic lighting, yet these visual enhancements are absent in the final version.

Beta content reveals that Castle Town featured more complex geometry, full bump maps, and proper lighting and shadows. New City's collision data implies a different building layout during development. Although much of the cut content remains dormant within the game, performance issues prevent it from being enabled. The game's reliance on basic albedo textures and ambient lighting contributes to its dull appearance.

The use of shaders has further hindered the game's visual quality. Most elements are rendered using the Terrain or Billboard shaders, with the latter having limited feature sets, lacking cascaded shadow maps (CSM), point lights, and precise shadow mapping. The most commonly used Billboard02 shader only supports per-vertex lighting, point lights, and no shadows.

While Sonic Team faced immense pressure to meet deadlines, many of these features were among the first to be removed. The game's lighting system, while theoretically flexible, was poorly implemented due to its limitations. Point lights, intended as small details, are restricted to a maximum of two per object, causing issues when stages like Flame Core and Dusty Desert exceed this limit.

The renderer struggles with prioritizing lights, resulting in random appearances and disappearances. Although attempts to optimize point lights exist, they have proven difficult to implement effectively.