looking at that other post I'd go the tile route, You can the also use the tiles for your a* map, you can use alpha blending on the edges and theres no reason why some tiles couldn't have several layers.
You could look at opengl render to texture tutorials, but tbh I wouldn't recommend it, the technique does slow things down and not all 3d cards can manage > 256x256 textures...
You could look at opengl render to texture tutorials, but tbh I wouldn't recommend it, the technique does slow things down and not all 3d cards can manage > 256x256 textures...