Learning Gravity, Basic Physics, and Camera Controls: An Angry Birds-like Game, Part I - Learn GameSalad for iOS: Game Development for iPhone, iPad, and HTML5 - page 185

display size. It will generate a visual effect as if the camera was going further
(zooming out) to show more on the display. This is exactly the effect you want.
The camera attributes are scene attributes. If you want a behavior to modify
them, you need to be able to access the scene attributes. What type of actors
can access the scene attributes? The unlocked actor instance!
Open the Scene Editor. Double-click the instance of the Projectile actor on the
scene. Unlock the instance by clicking the lock icon as per Figure 6-30.
Figure 6-30. Unlocking the Projectile instance
Expand the Otherwise section of the Touchrule. Then expand the Throwing rule.
Drag and drop an Interpolate behavior into the Throwing rule and, as shown in
Figure 6-31, change the settings to:
 Interpolate Attribute: Current Scene.Camera.Size.Width
 To: 920
 Duration: 2
 Function: Linear