GoKawiilMarathon Recompiled project uncovers unused rendering features in Sonic the Hedgehog (2006)
Developers working on the Marathon Recompiled project examined Sonic 06's rendering engine and found that many visual effects seen in beta footage, such as bump mapping in Kingdom Valley and complex geometry in Castle Town, were never fully removed from the game's code. Instead, these features exist in the game's Terrain and Billboard shader systems but were disabled in numbered variants, likely to help the game hit playable frame rates on hardware at launch.