Hi I'm using this version of cocos2d:

https://github.com/krzysztofzablocki/CCNode-SFGestureRecognizers

Which supports the UIGestureRecognizer within a CCLayer in a cocos2d scene like so:

@interface HelloWorldLayer : CCLayer <UIGestureRecognizerDelegate>
{
}

Now I want to make this custom gesture work within the scene, attaching it to a sprite in cocos2d:

#import <Foundation/Foundation.h>
#import <UIKit/UIGestureRecognizerSubclass.h>

@protocol OneFingerRotationGestureRecognizerDelegate <NSObject>
@optional
- (void) rotation: (CGFloat) angle;
- (void) finalAngle: (CGFloat) angle;
@end

@interface OneFingerRotationGestureRecognizer : UIGestureRecognizer
{
    CGPoint midPoint;
    CGFloat innerRadius;
    CGFloat outerRadius;
    CGFloat cumulatedAngle;
    id <OneFingerRotationGestureRecognizerDelegate> target;
}

- (id) initWithMidPoint: (CGPoint) midPoint
            innerRadius: (CGFloat) innerRadius
            outerRadius: (CGFloat) outerRadius
                 target: (id) target;
- (void)reset;
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event;

@end

#include <math.h>  
#import "OneFingerRotationGestureRecognizer.h"

@implementation OneFingerRotationGestureRecognizer

// private helper functions
CGFloat distanceBetweenPoints(CGPoint point1, CGPoint point2);
CGFloat angleBetweenLinesInDegrees(CGPoint beginLineA,
                                   CGPoint endLineA,
                                   CGPoint beginLineB,
                                   CGPoint endLineB);

- (id) initWithMidPoint: (CGPoint) _midPoint
            innerRadius: (CGFloat) _innerRadius
            outerRadius: (CGFloat) _outerRadius
                 target: (id <OneFingerRotationGestureRecognizerDelegate>) _target
{
    if ((self = [super initWithTarget: _target action: nil]))
    {
        midPoint    = _midPoint;
        innerRadius = _innerRadius;
        outerRadius = _outerRadius;
        target      = _target;
    }
    return self;
}

/** Calculates the distance between point1 and point 2. */
CGFloat distanceBetweenPoints(CGPoint point1, CGPoint point2)
{
    CGFloat dx = point1.x - point2.x;
    CGFloat dy = point1.y - point2.y;
    return sqrt(dx*dx + dy*dy);
}

CGFloat angleBetweenLinesInDegrees(CGPoint beginLineA,
                                   CGPoint endLineA,
                                   CGPoint beginLineB,
                                   CGPoint endLineB)
{
    CGFloat a = endLineA.x - beginLineA.x;
    CGFloat b = endLineA.y - beginLineA.y;
    CGFloat c = endLineB.x - beginLineB.x;
    CGFloat d = endLineB.y - beginLineB.y;

    CGFloat atanA = atan2(a, b);
    CGFloat atanB = atan2(c, d);

    // convert radiants to degrees
    return (atanA - atanB) * 180 / M_PI;
}

#pragma mark - UIGestureRecognizer implementation

- (void)reset
{
    [super reset];
    cumulatedAngle = 0;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    [super touchesBegan:touches withEvent:event];

    if ([touches count] != 1)
    {
        self.state = UIGestureRecognizerStateFailed;

        return;
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    [super touchesMoved:touches withEvent:event];

    if (self.state == UIGestureRecognizerStateFailed) return;

    CGPoint nowPoint  = [[touches anyObject] locationInView: self.view];
    CGPoint prevPoint = [[touches anyObject] previousLocationInView: self.view];

    // make sure the new point is within the area
    CGFloat distance = distanceBetweenPoints(midPoint, nowPoint);
    if (   innerRadius <= distance
        && distance    <= outerRadius)
    {
        // calculate rotation angle between two points
        CGFloat angle = angleBetweenLinesInDegrees(midPoint, prevPoint, midPoint, nowPoint);

        // fix value, if the 12 o'clock position is between prevPoint and nowPoint
        if (angle > 180)
        {
            angle -= 360;
        }
        else if (angle < -180)
        {
            angle += 360;
        }

        // sum up single steps
        cumulatedAngle += angle;

        // call delegate
        if ([target respondsToSelector: @selector(rotation:)])
        {
            [target rotation:angle];
        }
    }
    else
    {
        // finger moved outside the area
        self.state = UIGestureRecognizerStateFailed;
    }
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event 
{
    [super touchesEnded:touches withEvent:event];

    if (self.state == UIGestureRecognizerStatePossible)
    {
        self.state = UIGestureRecognizerStateRecognized;

        if ([target respondsToSelector: @selector(finalAngle:)])
        {
            [target finalAngle:cumulatedAngle];
        }
    }
    else
    {
        self.state = UIGestureRecognizerStateFailed;
    }

    cumulatedAngle = 0;
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    [super touchesCancelled:touches withEvent:event];

    self.state = UIGestureRecognizerStateFailed;
    cumulatedAngle = 0;
}

@end

Header file for view controller:

#import "OneFingerRotationGestureRecognizer.h"

@interface OneFingerRotationGestureViewController : UIViewController <OneFingerRotationGestureRecognizerDelegate>
@property  (nonatomic, strong) IBOutlet UIImageView *image;
@property  (nonatomic, strong) IBOutlet UITextField *textDisplay;
@end

then this is in the .m file:

gestureRecognizer = [[OneFingerRotationGestureRecognizer alloc] initWithMidPoint: midPoint
                                                                innerRadius: outRadius / 3 
                                                                outerRadius: outRadius
                                                                     target: self];
    [self.view addGestureRecognizer: gestureRecognizer];

Now my question is, is it possible to add this custom gesture into the cocos2d project found on that github, and if so, what do I need to change in the OneFingerRotationGestureRecognizerDelegate to get it to work within cocos2d. Because at the minute it is setup in a standard iOS project and not a cocos2d project and I do not know enough about UIViews and classing/ sub classing in obj-c to get this to work. Also it seems to inherit from a UIView where cocos2d uses CCLayer.

Kind regards,

Lewis.

I also realise I may have not included enough code from the custom gesture project for readers to interpret it fully, so the full project can be found here:

https://github.com/melle/OneFingerRotationGestureDemo