Actions

Actions are like orders given to any CCNode object. These actions usually modify some of the object's attributes like position, rotation, scale, etc. If these attributes are modified during a period of time, they are CCIntervalAction actions, otherwise they are CCInstantAction actions.

For example, the CCMoveBy action modifies the position property during a period of time, hence, it is a subclass of CCIntervalAction.

Example:

# Move a sprite 50 pixels to the right, and 10 pixels to the top over 2 seconds.
[sprite runAction: [CCMoveBy actionWithDuration:2 position:ccp(50,10)]];

The CCIntervalAction actions have some interesting properties:

• They can be accelerated using the time-altered actions
  • CCEaseIn
  • CCEaseOut
  • CCEaseInOut
  • CCSpeed
  • Etc. (See the ActionsEaseTest.m example for more info)
• All the relative actions (the ones ending in 'By') and some absolute actions (the ones ending in 'To') have a reverse action ([action reverse]) that executes the action in the opposite direction.

You can pause/resume all actions by using the CCActionManager:

# Pause actions
[[CCActionManager sharedManager ] pauseAllActionsForTarget:sprite ] ;
 
# resume actions
[[CCActionManager sharedManager ] resumeAllActionsForTarget:sprite ] ;

Basic actions are the ones that modify basic properties like:

• position
  • CCMoveBy
  • CCMoveTo
  • CCJumpBy
  • CCJumpTo
  • CCBezierBy
  • CCBezierTo
  • CCPlace
• scale
  • CCScaleBy
  • CCScaleTo
• rotation
  • CCRotateBy
  • CCRotateTo
• visible
  • CCShow
  • CCHide
  • CCBlink
  • CCToggleVisibility
• opacity
  • CCFadeIn
  • CCFadeOut
  • CCFadeTo
• r, g, b
  • CCTintBy
  • CCTintTo

Example:

CGSize s = [[CCDirector sharedDirector] winSize];
 
id actionTo = [CCMoveTo actionWithDuration: 2 position:ccp(s.width-40, s.height-40)];
id actionBy = [CCMoveBy actionWithDuration:2  position: ccp(80,80)];
 
[sprite1 runAction: actionTo];
[sprite2 runAction:actionBy];

Almost all actions have the reverse method implemented. Basically it creates a new action with the reverse behavior.

Example:

id move = [CCMoveBy actionWithDuration:2  position: ccp(80,80)];
 
id move_reverse = [move reverse];

The move_reverse action will be a CCMoveBy action of duration 2, but with the position value of ccp(-80,-80).