  We present how to implement special relativity in computer games. The
resultant relativistic world shows the time dilation and Lorentz contraction
exactly, not only for the player but also for all the nonplayer characters, who
obey the correct relativistic equation of motion according to their own
accelerations. Causality is explicitly maintained in our formulation by use of
the covariant velocities, proper times, worldlines, and light cones. Faraway
relativistic scenes can be accurately projected onto the skydome. We show how
to approximate a rigid body consisting of polygons, which is ubiquitous in
computer games but itself is not a relativistically invariant object. We also
give a simple idea to mimic the Doppler effect within the RGB color scheme.
