reverse Animation « cocos2d for iPhone

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reverse Animation

(9 posts) (6 voices)

Started 2 years ago by raegtime
Latest reply from iisystems

Tags:

raegtime
Member

id myaction = [Animate actionWithAnimation: animation restoreOriginalFrame:NO];
id actionrev = [myaction reverse];
[bg runAction : actionrev];

hi, i was trying to reverse an animation with this code... but the debugger was alert this msg:

*** Terminating app due to uncaught exception 'ReverseActionNotImplemented', reason: 'Reverse Action not implemented'
2009-07-13 16:19:56.906 FanTool[374:207] Stack: (
808001701,
805397928,
129899,
317153,
281889,
278763,
230321,
815423588,
815420524,
814968388,
814966908,
839149932,
807750263,
807747947,
839144100,
814678908,
814672532,
8909,
8764
)
terminate called after throwing an instance of 'NSException'
Program received signal: “SIGABRT”.
(gdb)

Posted 2 years ago #
Joao Caxaria
Member
Yes, it's correct. The reverse method is not implemented in the Animate class, so it calls the base (IntervalAction) method. The base in turn does this:
```
NSException* myException = [NSException
								exceptionWithName:@"ReverseActionNotImplemented"
								reason:@"Reverse Action not implemented"
								userInfo:nil];
	@throw myException;
```
So apparently you can't reverse a "Animate" class. But you probably already saw that by stepping into the code.
Posted 2 years ago #
raegtime
Member

so its not possible to reverse an animation? :(

Posted 2 years ago #
Joao Caxaria
Member

Well, it is possible to reverse a animation.. just not that one (myaction) in particular.

What is the 'animation' object type?

Posted 2 years ago #
riq
Key Master

@raegtime: You could code the Animate "reverse" action. It shouldn't be difficult.

Posted 2 years ago #

Sean Carmody
Member

I was running into this same problem with reverse.

What I did was switch from using MoveTo to MoveBy. Reverse works fine with MoveBy.

id float4 = [MoveBy actionWithDuration:3 position: ccp(endx, endy)];
id float4_back = [float4 reverse];
id float4_seq = [Sequence actions: float4, float4_back, nil];
id float4_forever = [RepeatForever actionWithAction:float4_seq];
[sprite runAction:  float4_seq];

Posted 2 years ago #

shadaz
Member

I came across this same issue today, if I wanted to reverse an animation where is the best place to do this? I noticed it grabs the current frame in the update function in IntervalAction.m Can someone please give a hint where to cleanly implement this?

Posted 2 years ago #

shadaz
Member

While waiting for a solution, I was able to implement reverse of animation in "IntervalAction.m", however i had to modify cocos code, is there a more elegant way to do this with a subclass/override so I dont have to fix this every time I update the core cocos code?

-(void)reverse
{
	isReverse = true;
}

-(void) update: (ccTime) t
{
	NSUInteger idx=0;

	ccTime slice = 1.0f / [[animation frames] count];

	if(t !=0 )
		idx = t/ slice;

	if (isReverse)
		idx = (idx - [[animation frames] count]) *-1; 

	if( idx >= [[animation frames] count] ) {
		idx = [[animation frames] count] -1;
	}
	id<CocosNodeFrames> sprite = (id<CocosNodeFrames>) target;
	if (! [sprite isFrameDisplayed: [[animation frames] objectAtIndex: idx]] ) {
		[sprite setDisplayFrame: [[animation frames] objectAtIndex:idx]];
	}
}

Posted 2 years ago #

iisystems
Member

Can you guys please post a bug report on this with the patch so Riq can integrate it? I came across this back in May and it seems my bug report has disappeared...

Posted 2 years ago #

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