Terrain in Games

Traditional implementation of terrain in games (1995-2002)

Navigational Constraints

The type of terrain used in a game depends on the range of navigation needed.  Some common styles of navigation are:

  1. Top-down games only let you look at a downward angle, and do not have to deal with a wide range of distances.  Hither clipping and LOD is greatly simplified or not needed.
  2. Unconstrained ground games let you look up or down, and get close to the surface.  They must allow a wide range of distances and levels of detail, and deal with hither clipping.  Some have third-person display modes, but allow the full navigational freedom of a 1st-person point of view.
  3. Unconstrained air games are similar, but do not have to deal with drawing near objects/scenery accurately.

Traditionally, each of these styles had different tradeoffs resulting in different algorithms.  More recently with the rise of powerful GPUs (2002-) terrain rendering systems have tended to have a more unified approach which can handle any style of navigation.

Top-down examples

Unconstrained ground examples

Unconstrained air examples