Is there any 2D/2.5D isometric game engine available out there that uses a coordinate system, rather than a tile-based system? I'm getting tired of seeing all of these tile-based game engines out there for isometric games. I think coordinate-based games look so much better than tile-based ones. I'm looking for an engine that replicates the seamless backgrounds seen in games like Baldur's Gate and Planescape: Torment, rather than the blocky tiled environments of RPG Maker games and the like, which seem to be everywhere.
As they say in the PS:T vision document: "Tiling is for bathrooms, not games."