22 1. Introduction
developers to employ various optimizations in the rendering engine of an RTS
game.
Older games in the genre employed a grid-based (cell-based) world con-
struction, and an orthographic projection was used to greatly simplify the ren-
derer. For example, Figure 1.8 shows a screen shot from the classic RTS Age
of Empires.
Modern RTS games sometimes use perspective projection and a true 3D
world, but they may still employ a grid layout system to ensure that units and
background elements, such as buildings, align with one another properly. A
popular example, Command & Conquer 3, is shown in Figure 1.9.
Some other common practices in RTS games include the following tech-
niques.Figure 1.9. Command & Conquer 3.