@D2 : Will this be a 3D Game Engine? What you desire can be done, but, how you handle the transition is where the trick will be.
Below is how I'm handling area transitions in my FPSRPG. First, I'ved divided the 3D Maps into three types: World, Area, and Stage. World Maps represent Realms and Cities. Area Maps represent Shops, Inns, Dungeons, Arenas, etc. Stage maps are 3D GUIs used to communicate with NPCs.
To visualize how a World Map will work, imagine a relatively small 3D terrain with some hills and valleys. Small 3D Castles (Icons) are placed in locations on the terrain. These icons represent a Cities.
You navigate the terrain in first person, when you collide with Icon a City World map is loaded that presents with you a World map with icons that represent Shops/Inns/Dugeons in the City. Note: Realm and City World maps can also have special Icons that teleport you to secret area maps.
When you enter a Shop/Inn/Dungeon a smaller more Detailed Area Map is loaded. Area Maps are more like your traditional Deathmatch FPS level maps. These maps can be populated NPCs, Enemies, Doors, Lifts, Teleporters, Traps, and Powerups. You navigate these maps in first person.
When you come in contact with NPCs in a area map, a stage map is loaded. A stage map is special 3D GUI map in which you can navigate FP and click on items via mouse to select. All GUIs in the game are a Stage maps.
I have sacraficed a seamless transition in favor of a Loading Screen the provides NEWS, Hints, and Ads during loading.
Below is how I'm handling area transitions in my FPSRPG. First, I'ved divided the 3D Maps into three types: World, Area, and Stage. World Maps represent Realms and Cities. Area Maps represent Shops, Inns, Dungeons, Arenas, etc. Stage maps are 3D GUIs used to communicate with NPCs.
To visualize how a World Map will work, imagine a relatively small 3D terrain with some hills and valleys. Small 3D Castles (Icons) are placed in locations on the terrain. These icons represent a Cities.
You navigate the terrain in first person, when you collide with Icon a City World map is loaded that presents with you a World map with icons that represent Shops/Inns/Dugeons in the City. Note: Realm and City World maps can also have special Icons that teleport you to secret area maps.
When you enter a Shop/Inn/Dungeon a smaller more Detailed Area Map is loaded. Area Maps are more like your traditional Deathmatch FPS level maps. These maps can be populated NPCs, Enemies, Doors, Lifts, Teleporters, Traps, and Powerups. You navigate these maps in first person.
When you come in contact with NPCs in a area map, a stage map is loaded. A stage map is special 3D GUI map in which you can navigate FP and click on items via mouse to select. All GUIs in the game are a Stage maps.
I have sacraficed a seamless transition in favor of a Loading Screen the provides NEWS, Hints, and Ads during loading.