Question

I have an sprite the I need to rotate it with touch but it is located in a different layer. Is it possible to update it’s position?

E.G.
Sprite has it’s own layer but it’s position needs to be updated within the main gamescene

here is what I have so far.

#import <Foundation/Foundation.h>
#import "cocos2d.h"
#import "GameScene.h"



@interface G : CCLayer {

    CCSprite *g;

    CGFloat gRotation;
}

@end

------------------------------------------
#import "G.h"


@implementation G

-(id) init
{
    if ((self = [super init]))
    {
        CCLOG(@"%@: %@", NSStringFromSelector(_cmd), self);

        g = [CCSprite spriteWithFile:@"g.png"];

        [self addChild:g z:-1];

        //[self scheduleUpdate];
        if (g.rotation == 360)
        {
            [self unscheduleUpdate];
        }
    }
    return self;
}

- (void)update:(ccTime)delta
{
    g.rotation = gRotation;
}

- (void)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{

}

- (void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];

    CGPoint firstLocation = [touch previousLocationInView:[touch view]];
    CGPoint location = [touch locationInView:[touch view]];

    CGPoint touchingPoint = [[CCDirector sharedDirector] convertToGL:location];
    CGPoint firstTouchingPoint = [[CCDirector sharedDirector] convertToGL:firstLocation];

    CGPoint firstVector = ccpSub(firstTouchingPoint, g.position);
    CGFloat firstRotateAngle = -ccpToAngle(firstVector);
    CGFloat previousTouch = CC_RADIANS_TO_DEGREES(firstRotateAngle);

    CGPoint vector = ccpSub(touchingPoint, g.position);
    CGFloat rotateAngle = -ccpToAngle(vector);
    CGFloat currentTouch = CC_RADIANS_TO_DEGREES(rotateAngle);

    gRotation += currentTouch - previousTouch;
}

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{

}

- (void) dealloc
{
    CCLOG(@"%@: %@", NSStringFromSelector(_cmd), self);

    [super dealloc];
}

@end

GameScene

#import "GameScene.h"
#import "MainMenu.h"
#import "G.h"


@implementation GameScene

+(CCScene *) scene
{
    CCScene *scene = [CCScene node];
    GameScene *layer = [GameScene node];

    [scene addChild: layer];
    return scene;
}

-(void) tapG: (id) sender
{

    G *gView;
    gView = [[G alloc] init];
    gView.position = ccp(100, 100);

    [self.parent addChild:gView z:1001];

    [gView schedule:@selector(update:)];

    [gView release];
}
-(id) init
{
    if ((self = [super init]))
    {
tG = [CCMenuItemImage itemFromNormalImage:@"tp.png" selectedImage:@"tp.png"  disabledImage:@"tpaperd.png" target:self selector:@selector(tapG:)];

        gt = [CCMenu menuWithItems:tG, nil];
        gt.position = ccp(210, 80);
        [gt alignItemsHorizontallyWithPadding:10];

        [self addChild:gt z:0];

    }
    return self;
}
- (void) dealloc
    {
        CCLOG(@"%@: %@", NSStringFromSelector(_cmd), self);

        [super dealloc];
    }

It brings up the sprite but the sprite does not rotate.

Answer 1

you can schedule updates for another layer.

are you sure your G layer is set to be touch enabled? try gView.isTouchEnabled = YES; after allocating gView. you may need to confirm to the protocol. Add <CCStandardTouchDelegate> to your CCLayer interface: @interface G : CCLayer <CCStandardTouchDelegate> { ....

also you can schedule -(void)update:(ccTime)delta method using [gView scheduleUpdate]; it will give the same result but its more convenient.