Sprite Action not Rotating « cocos2d for iPhone

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Sprite Action not Rotating

(27 posts) (5 voices)

Started 2 years ago by Osiris
Latest reply from Osiris

Tags:

ccrotate

Osiris
Member

I have the following action when a ship collides with an enemy:

id action1 = [RotateBy actionWithDuration:2.0 angle:360];
id action2 = [ScaleBy actionWithDuration:2.0 scaleX:2.0 scaleY:2.0];
id action3 = [FadeOut actionWithDuration:2.0 ];
id action4 = [CallFuncN actionWithTarget:self selector:@selector(resetShipSprite:)];

id actionSpawn = [Spawn actions: action1, action2, action3, nil];
id actionSeq = [Sequence actions: actionSpawn, action4, nil];

Most if it works fine and I had this pointed out to me by someone else, the sprite is not rotating. Its scaling, fading at the same time and the callBack is occuring afterwards, so everything else is good. Its just not rotating.

any ideas?

Posted 2 years ago #

natanavra
Member

Try doing only a rotate action, maybe the Scale or Fade cancel the rotation somehow?

Posted 2 years ago #
Clain
Member

Are you using the latest SVN sources ? A change has been made recently so that a RotateTo action now rotates with the smaller angle possible. eg : if your sprite had a rotation of say, 340 and you applied a RotateTo... angle:20 action, sometimes the sprite rotated by +40 to reach the new angle of 20, and sometimes it rotated by -320. It was fixed to always rotate by +40 in such a case.

The fix should have affected the RotateTo class only. But maybe it affected the RotateBy class as a side effect. Can you try with a different angle value for your action1 (something like 200 for example) ?

Posted 2 years ago #
riq
Key Master

it should work. if it doesn't it's a bug. and if it is a bug, could you open a issue with it attaching the code to reproduce it ? please, specify which cocos2d version are you using.
thanks.

Posted 2 years ago #
Osiris
Member

usually boils down to me doing something wrong :)

I'll be glad to open an issue.

Posted 2 years ago #
Osiris
Member

OK, now I feel stupid again... I don't see where to open an issue? Its probably right in front of me.

Posted 2 years ago #
cjl
Member

@Osiris: I just tried your code snippet with the latest revision of Cocos2d, and my sprite performed all three actions simultaneously, without any problems.

So, maybe the bug is somewhere in your code. Could you post more of your code, so we can take a look?

Posted 2 years ago #

Osiris
Member

ok, the area is really simple.

if (!dead && (CGRectContainsPoint(enemyBounds, shipPoint))) {

		//  *** DETECTED COLLISION BETWEEN ALIEN AND SHIP ***

		[[SimpleAudioEngine sharedEngine] playEffect:@"death.wav"];

		thetaMod = 0;

		id action1 = [RotateBy actionWithDuration:2.0 angle:360];
		id action2 = [ScaleBy actionWithDuration:2.0 scaleX:2.0 scaleY:2.0];
		id action3 = [FadeOut actionWithDuration:2.0 ];
		id action4 = [CallFuncN actionWithTarget:self selector:@selector(resetShipSprite:)];

		id actionSpawn = [Spawn actions: action1, action2, action3, nil];
		id actionSeq = [Sequence actions: actionSpawn, action4, nil];

		[ship runAction:actionSeq];

		lives--;
		dead = YES;

	}

Posted 2 years ago #

Osiris
Member

I would expect that if I can see it scale and fade, I should also see it rotate? I just took out actions2 and 3 from the Spawn and tried to run only the rotate and nada... zip the sprite just sat there.

Im running 8.0 release

Posted 2 years ago #
cjl
Member

@Osiris

Does is work if you call the action directly? Try something like:

[ship runAction:[RotateBy actionWithDuration:2.0 angle:360]];

Also, are there any other actions already running on the ship when your code is called?

Posted 2 years ago #
Osiris
Member
I will try that and report back,I was getting ready to say there are no other actions but....

im not calling any runActions on the sprite, but my main loop is calling
```
ship1.rotation = (NSInteger) CC_RADIANS_TO_DEGREES(theta);
```
to keep the ship aligned.

i suppose the action begins running, but so does the loop, resetting the rotation?
Posted 2 years ago #
Osiris
Member

Ok, I got it to work... I put an unSchedule for step: right before my runAction and then rescheduled step: in my spriteReset Callback and it seems to work. It seems convoluted though. Is there a more elegant way? maybe with a [pause scheduler] [resume scheduler]??

Posted 2 years ago #
cjl
Member

maybe you could try calling stopAction or stopAllActions on ship1, before running your new action?

Posted 2 years ago #
Osiris
Member

I thing stopAllActions would not work because my current facing angle is always being adjusted in the step: so, but the time the actions were scheduled to run, I would have checked and reset the current rotation angle 120 times.

(unless I misunderstand how all this work)

Posted 2 years ago #

natanavra
Member

@Osiris, you have the dead property, you can use it to filter your action in the step but you should put the dead=YES in the beginning of the if mentioned above... Something like this :

-(void)mainLoop:(ccTime)delta {
       ...................
       if(!mySprite.dead) {
            [mySprite runAction:myAction];
       }
       ....................
}

This would filter the action that happens in the main loop, notice you must put this change:

if (!dead && (CGRectContainsPoint(enemyBounds, shipPoint))) {

		//  *** DETECTED COLLISION BETWEEN ALIEN AND SHIP ***
                dead = YES;
                ----------------------------
}

Hope this helps, keep us updated.

Posted 2 years ago #

cjl
Member

@Osiris: Natanavra has the correct answer.

In fact, now that I look a little closer at what you are doing, I'll bet your RotateBy action is being run on your ship1, it's just that ship1's rotation is being reset everytime your step method is called.

So, as Natanavra said, in your step method you need to introduce some logic so that if a ship is dead you don't reset the rotation.

Posted 2 years ago #
Osiris
Member

Thank you, I'll try that right after dinner!

Posted 2 years ago #
Osiris
Member
```
-(void)mainLoop:(ccTime)delta {
       ...................
       if(!mySprite.dead) {
            [mySprite runAction:myAction];
       }
       ....................
}
```
works very well... thanks

on a side note, I'm now attempted to "objectize" the entire code more and I'm finding myself lacking in some basic understanding I think.

I read and read the touchesTest code and have adopted (successfully I think) the paddle code to control my movement buttons that control that ship. I believe I understand applying the touches logic to the object rather than my entire program - like I was doing before.

However,

I have in my init:
```
MyButton *upButton = [MyButton buttonWithTexture:upButtonTexture];

		//Sprite *upButton = [Sprite spriteWithFile:@"BTN_arrowUP.png"];

		upButton.position = CGPointMake(435, 100);
		upButton.scale=1.5f;
		[upButton setOpacity:128];

		[self addChild:upButton z:3 tag:7];
```
I don't know enough about objects vs the sprites they are replacing yet to change the accessors any more than that..
So I have my up and down buttons defined that way and the MyButton class should be handling the touches in a similar way to the paddle class.

In my step: schedule, i have:
```
Sprite *ship1 = (Sprite *)[self getChildByTag:1];
	Sprite *ship2 = (Sprite *)[self getChildByTag:11];

	MyButton *upButton (MyButton *)[self getChildByTag:7];
	MyButton *downButton (MyButton *)[self getChildByTag:8];
```
and im getting errors on the "getChildByTag:" I'm not sure what to do next?
Posted 2 years ago #
Osiris
Member

does "getChildByTag" work with regular objects?

Posted 2 years ago #
Osiris
Member
Again, I continue to dig... I found it.
```
MyButton *upButton (MyButton *)[self getChildByTag:7];
MyButton *downButton (MyButton *)[self getChildByTag:8];
```
should be:
```
MyButton *upButton = (MyButton *)[self getChildByTag:7];
MyButton *downButton = (MyButton *)[self getChildByTag:8];
```
The objects are working very well now.. I figured out how to make my own setters for "Pushed" and return the proper state when asked in the main loop. I've never done this kind of programming before and I think I'm slowing getting the hang of it!
Posted 2 years ago #
natanavra
Member

This looks quite well Osiris, one more thing... you could create instance variables inside your class to manage the button...
And btw do you implement the button control/behaviour inside the button class? or do you handle on touches inside gameLayer??

Posted 2 years ago #
Osiris
Member

I have now setup button control / behavior inside the button class... much more elegant!

I do have a question, I have been trying both ways... I used to create a bullet in init and then move it offscreen until needed.

I'm experimenting with creating the bullet in a fireBullet function that calls a bullet sequence of actions. In the CallBack for that action, I have a removeSprite function where I was trying to [bullet release] but im getting a runtime error. Im sure its because im pulling the rug out of the bullet sprite, but I cannot imagine Im supposed to keep that sprite around and keep creating new ones? That would be a huge leak in my feable little brain.

Is there a standard way to remove these sprites when you are finished with them?

Posted 2 years ago #
natanavra
Member

I think ur sprite is either running some action or something like that.
I would create a bulletManager array (pre alloc) and call the bullets via the user input.
And until I get user input I'd stack them off screen and overide draw method to draw them only when inside screen.
You should create a bullet class and have a custom init function + a function to get user touch location and create actions accordingly:
-(void) setDirection:(CGPoint)touchPoint

Also have a bool property for your bullet class to know if a certain bullet can be used, e.g.

BOOL usable;

Wow, that was quite a writing exp (written from myPhone)...
Hope this helps, if you have any further questions I'll sure try to help!

Posted 2 years ago #
Osiris
Member

it helps a lot. thanks

Posted 2 years ago #
Osiris
Member

so its not a good idea to keep creating and releasing sprites?

Posted 2 years ago #
natanavra
Member

Nope, it's quite expensive if using .png files and after creating a bullet manager I gained uber speed almost no slowdowns, now I need enemy manager.
btw everytime I created a sprite to shoot and allocate chipmunk stuff for it, it was about 300K alloc (expensive in the long run when shooting 20 bullets in a row)

Posted 2 years ago #
Osiris
Member

very good to know. thanks!

Posted 2 years ago #

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