I was just thinking about spherical terrains...
Heres an idea on how a spherical terrain will be loaded.
BT will use Cubed Spheres for Spherical Terrain:
http://www.mathworks.com/matlabcentral/fx_files/25027/2/cubedsphere.png
Spherical terrains will use cubemaps. There will be 3 ways to load a spherical terrain
BT CreateTerrain 1
BT SetTerrainSource 1, "mycubemap.png:C"
The :C on the end tells BT that this should be viewed as a cube map so BT will automatically see this as a spherical terrain.
BT SetTerrainSource 1, "myspheremap.png:S"
This is for loading a sphere map as a source. Also tells BT that the terrain is spherical
BT SetTerrainSource 1, "${C}-${X}-${Y}.png:B=4"
This will make BT look at separate files for the terrain. ${C} will be replaced with the face of the cube that BT is looking for. ${X} and ${Y} are the region on that face that needs to be found. Using ${C} implies the :C option.
:B=4 tells BT that the size of each face will be (4, 4). (this must be set for spherical terrains as it needs to know the exact size of each face). This would make BT allocate 4x4 regions for each face. (So in this example, the terrain will have 1024x1024 vertices on each face and 4096 vertices around the equator. Remember that regions are always 256x256 vertices)
If your using the above data source. The filename for one of the regions on the top face will be: "PZ-0-0.png"
PZ means positive Z. In BT3 the Z axis is up! (I know this is a bit annoying as the Y axis is usually the up one in DBPro, but this does acctually simplify a lot of the BT3 commands as the X and Y always face the same way).
The names of all the faces will be:
PX, NX, PY, NY, PZ, NZ
Let me know what you think about that
I'm also thinking about multilevel regions. This will allow more and more detail to be loaded as you get closer to the terrain (alot like Google Earth). This will be quite complex to implement but I think I might be able to do it with some careful designing, lots of ink and paper, and a hell of a lot of tea!
Another cool thing about the multilevel idea is that you can have mountains in the distance which don't take up much RAM (as they are stored at a much lower detail than the stuff near to the player).
