Graphics Reference
In-Depth Information
Start() begins by getting a reference to the AI controller component. It does this with
Unity's GetComponent() function, employed here as a keyword, meaning that it will look
for the component on the gameObject this script is attached to:
void Start ()
{
// first, let's try to get the AI control script
// automatically
AIControlComponent= GetComponent<BaseAIController>();
Next, the regular gameObject and transform references are cached, and a quick null
check is made to make sure that we have an AI controller:
myGO= gameObject;
myTransform= transform;
// quick null check, to warn us if something goes wrong
if( AIControlComponent == null )
{
Debug.LogWarning("SetAIChaseTargetBasedOnTag cannot
find BaseAIController");
}
The main part of this script is within LookForChaseTarget(), but it is not something
we need to do every step or frame of the game running. Instead, InvokeRepeating sched-
ules a repeated call to it every 1.5 s:
InvokeRepeating( "LookForChaseTarget", 1.5f, 1.5f );
}
This script will not work if it has not been able to find an AI controller script
(BaseAIController.cs) attached to the same gameObject. LookForChaseTarget() does a
quick null check to get started:
void LookForChaseTarget ()
{
// null check
if( AIControlComponent == null )
return;
To find another chase target, references to all of the potential gameObjects need to
be retrieved and put into an array. GameObject.FindGameObjectsWithTag() returns an
array of all gameObjects in the scene whose tag matches the one passed in as a parameter.
The defaultTagFilter variable is actually just a string containing the word “enemy,” which
corresponds to the tag with the same name set in the Unity editor:
GameObject[] gos = GameObject.FindGameObjectsWithTag
( defaultTagFilter );
A foreach loop now steps through each gameObject in the array named gos, which
holds all of the tagged objects returned by the call to FindGameObjectsWithTag():
