Game Development Reference
TFD Trigger Examples
TFD triggers are located along the flows. The Ammo TFD template, provided in
Appendix D, will be used to illustrate how to incorporate all of the Defect Triggers into
a TFD. It has a few more flows than the TFD you constructed in Chapter 11, but is it
“complete�? in terms of triggers? Use it in a specific context— Unreal Tournament 2004
for the PC—and see what you can dig up.
To begin with, the template includes plenty of Normal trigger flows such as GetGun and
GetAmmo when you have neither ( NoGunNoAmmo ). However, the same event can represent
different triggers depending on its context with respect to the states it's leaving and
entering. For example, GetAmmo when you already have the maximum amount is a case
of performing a function when a resource (ammo) is at its maximum. This qualifies
as a Stress trigger. Shooting a gun with no ammo falls on the other end of the spectrum
where the ammo resource is at a minimum (0). Figure 15.10 shows the Ammo TFD
template with these Stress triggers highlighted.
Figure 15.10 Ammo TFD template with Stress flows highlighted.