Coding4Fun

Building the Fire Bullet Projectile Behaviors

Since our game uses a health bar, one thing we need to do is add and modify behaviors for the Fire Bullet projectile that was set up in the Adding a Shooting Behavior section.

Updating the DisappearOnCollision Behavior

The first change we're going to make is to the existing "DisappearOnCollision" behavior. To do this, select the Fire Bullet from the list of actors and click the Behaviors button to see the list of behaviors for the Fire Bullet, as shown in Figure 2-50.

Figure 2-50. Default behaviors for the Fire Bullet actor

By default, the "DisappearOnCollision" event is set to make both of the colliding actors disappear on a collision event. This is bad because it would make the Main actor disappear from the scene, which is not what we want. Instead, we want the Fire Bullet to disappear on a collision and we want to subtract the Health property for the Main actor.

To update the "DisappearOnCollision" behavior, click the Sender button (see Figure 2-50) and select the "Myself (the current instance of Fire Bullet)" radio button, as shown in Figure 2-51.

Figure 2-51. Updating the disappear behavior so that the current instance of the Fire Bullet actor disappears

Creating a Custom Code Behavior to Lower the Health Property

The next thing we want to ...