Even though virtually all games until the 1990s were two-dimensional games, they weren't all limited to a single plane of depth. Many added effects such as a moving, three-dimensional-looking background and multiple planes of depth. A good example of this is the well-known 1991 (1992 for USA) Super Nintendo Entertainment System (SNES) game The Legend of Zelda: A Link to the Past. This game features a top-down view, and both inside and outside dungeons, there are many levels of depth that change which objects can interact with each other.
The important thing about making something appear 3D when it's on a flat surface is scaling. The term for this is perspective projection, which basically means that more distant objects appear smaller. While this may seem blindingly obvious, the exact ratio for it is important to get a natural look.
In this chapter, we will cover these topics:
Implementing perspective to achieve rotation and other effects
Adding isometric...