FUNDAMENTALS OF GAME DESIGN, SECOND EDITION
Camera Model
For many years, computer strategy games displayed their game worlds in two dimensions as seen from above, effectively treating the video screen like a map or a tabletop game board. Later games adopted an isometric perspective in which buildings and units appeared to stand up above the surface of the landscape, although the underlying model of the world was still 2D. With the arrival of 3D display engines, strategy games began to include fully three-dimensional worlds with 3D modeled hills, valleys, and other landscape features, as well as 3D modeled units.
Regardless of the display technology, players of strategy games need to see the big picture, the overall view of the game world. The player cannot plan an effective strategy if she is forced to view the world from one avatar point of view. Unless you're trying to model what warfare was like for a general of ancient times—back when generals fought alongside their troops—you should choose some form of aerial perspective. The player will also find it valuable if you allow her some control over the camera so that she can zoom out to see the whole battlefield or zoom in
on a particular fight and move the camera around to different points of view. See the Total War series for a good example. A few games implement intelligent cameras that automatically move to locations where particularly important events are taking place, but if you do this, be sure the player can turn it off. In a strategy game, especially a real-time one, the player needs control over what she's seeing.
