Interiors define large objects, such as buildings, and spaces that players and entities can move around in. These interiors are stored in a format called DIF, which utilizes a Binary Space Partition (BSP) collision scheme, similar to that found in any Quake-based game engine. DIFs can be created using QuArK or any other Valve 220 format .map editing program. At this time there is no native .map editor available for the Macintosh platform, though QuArK will run under Virtual PC 6 and it goes without saying that you're home free with an Intel based mac and bootcamp

Torque Game Engine uses Portal-based interiors to seamlessly integrate your interiors with the terrain engine. Torque also features animated lightmaps so you can add color cycling, fading, flickering, among other effects designed to help you achieve a desired environmental mood or style. Detail brushes reduce the number of portals generated. Surfaces won't be split during the BSP creation process, so you can save on polygons and collision complexity through proper use of detail brushes.