Interactive Objects and MissionMgr - Creating E-Learning Games with Unity - page 31

1. To use the new script wizard, right-click inside the Chapter2 folder of the
Project tab and add a C# script named InteractiveObj .
2. To enable our interactive object to rotate about its own axis at a user spe-
cified rate, we need to add two parameters: a rotation axis and a rotation
speed, as shown in the following code:
public Vector3 rotAxis;
public float rotSpeed;
3. We will add a private reference to the customGameObject component for
this GameObject so that we don't have to look it up at runtime. This can be
done with the following line of code:
private customGameObject gameObjectInfo;
4. We will also add an ObjectInteraction member variable. This will be the
code that specifies what will happen to our gameObject when the player in-
teracts with it. There may be many interactions that an interactive object can
implement; we will start our example with OnCloseEnough and will complete
this in the OnTriggerEnter method, as shown in the following code:
public objectInteraction OnCloseEnough;
5. In the Start() method, we will search for the CustomGameObject com-
ponent attached to gameObject . If it is found, we will store the reference
in the gameObjectInfo private variable. Remember to always check that
gameObjectInfo is not null so that debugging the code is a straightforward
process, as shown in the following code:
gameObjectInfo =
this.gameObject.GetComponent<customGameObject>();
if (gameObjectInfo)
gameObjectInfo.validate();
6. In the Update() method, we will apply a simple rotation to the object around
the specified rotAxis parameter. We will rotate the object with the speed
given in rotSpeed multiplied by Time.deltaTime so that the number of
rotations is a function of the elapsed time rather than the frame time, as
shown in the following code: