Movement of a sprite with a joystick?

How do I apply moveme开发者_Python百科nt to a Sprite with a Joystick in Cocos2d?

All you have to do is have a sprite and a SneakyJoyStick already done. To do the SneakyJoyStick, just google sneakyinput and click on the third link.

Once you have this done, and you have your project open (duh...), look at the below code:

Here is the HelloWorldLayer.h: (it can be different, just as long as it is a layer)

#import "cocos2d.h"

@class SneakyJoystick;

@interface HelloWorldLayer : CCColorLayer {
    SneakyJoystick *leftJoyStick;
    CCSprite *character;
    CCNode *mainCharacter;
    CGPoint stickPosition;
    float degrees;
    CGPoint velocity;
    BOOL autoCenter;
    BOOL isDPad;
    BOOL hasDeadzone; //Turns Deadzone on/off for joystick, always YES if ifDpad == YES
    NSUInteger numberOfDirections; //Used only when isDpad == YES

    float joystickRadius;
    float thumbRadius;
    float deadRadius; //Size of deadzone in joystick (how far you must move before input starts). Automatically set if isDpad == YES

    //Optimizations (keep Squared values of all radii for faster calculations) (updated internally when changing joy/thumb radii)
    float joystickRadiusSq;
    float thumbRadiusSq;
    float deadRadiusSq;
}

@property (nonatomic, readonly) CGPoint stickPosition;
@property (nonatomic, readonly) CGPoint playerPosition;
@property (nonatomic, readonly) CGPoint playerPosition2;
@property (nonatomic, readonly) float degrees;
@property (nonatomic, readonly) CGPoint velocity;
@property (nonatomic, assign) BOOL autoCenter;
@property (nonatomic, assign) BOOL isDPad;
@property (nonatomic, assign) BOOL hasDeadzone;
@property (nonatomic, assign) NSUInteger numberOfDirections;

@property (nonatomic, assign) float joystickRadius;
@property (nonatomic, assign) float thumbRadius;
@property (nonatomic, assign) float deadRadius;

-(id)initWithRect:(CGRect)rect;

@end

And here is the HelloWorldLayer.m:

    // Import the interfaces
#import "HelloWorldLayer.h"
#import "SneakyJoystick.h"
#import "SneakyJoystickSkinnedBase.h"
#import "ColoredCircleSprite.h"

#define SJ_PI 3.14159265359f
#define SJ_PI_X_2 6.28318530718f
#define SJ_RAD2DEG 180.0f/SJ_PI
#define SJ_DEG2RAD SJ_PI/180.0f

@interface SneakyJoystick(hidden)
-(void)updateVelocity:(CGPoint)point;
-(void)setTouchRadius;
@end

// HelloWorldLayer implementation
@implementation HelloWorldLayer

@synthesize
stickPosition,
degrees,
velocity,
autoCenter,
isDPad,
hasDeadzone,
numberOfDirections,
joystickRadius,
thumbRadius,
deadRadius,
position,
playerPosition,
playerPosition2;

-(id)initWithRect:(CGRect)rect
{
    self = [super init];
    if(self){
        stickPosition = CGPointZero;
        playerPosition = ccp(150,150);
        degrees = 0.0f;
        velocity = CGPointZero;
        autoCenter = YES;
        isDPad = NO;
        hasDeadzone = NO;
        numberOfDirections = 4;

        self.joystickRadius = rect.size.width/2;
        self.thumbRadius = 32.0f;
        self.deadRadius = 0.0f;

        //Cocos node stuff
        position_ = rect.origin;
    }
    return self;
}

-(void)updateVelocity:(CGPoint)point
{
    // Calculate distance and angle from the center.
    float dx = point.x;
    float dy = point.y;
    float dSq = dx * dx + dy * dy;

    if(dSq <= deadRadiusSq){
        velocity = CGPointZero;
        degrees = 0.0f;
        stickPosition = point;
        return;
    }

    float angle = atan2f(dy, dx); // in radians
    if(angle < 0){
        angle       += SJ_PI_X_2;
    }
    float cosAngle;
    float sinAngle;

    cosAngle = cosf(angle);
    sinAngle = sinf(angle);

    // NOTE: Velocity goes from -1.0 to 1.0.
    if (dSq > joystickRadiusSq || isDPad) {
        dx = cosAngle * joystickRadius;
        dy = sinAngle * joystickRadius;
    }

    velocity = CGPointMake(dx/joystickRadius, dy/joystickRadius);
    degrees = angle * SJ_RAD2DEG;

    // Update the thumb's position
    stickPosition = ccp(dx, dy);
}

+(id) scene
{
    // 'scene' is an autorelease object.
    CCScene *scene = [CCScene node];

    // 'layer' is an autorelease object.
    HelloWorldLayer *layer = [HelloWorldLayer node];

    // add layer as a child to scene
    [scene addChild: layer];

    // return the scene
    return scene;
}

-(id) init
{
    // always call "super" init
    // Apple recommends to re-assign "self" with the "super" return value
    if( (self=[super initWithColor:ccc4(255,255,255,255)] )) {
        self.isTouchEnabled = YES;

        SneakyJoystickSkinnedBase *leftJoy = [[[SneakyJoystickSkinnedBase alloc] init] autorelease];
        leftJoy.position = ccp(72,72);
        leftJoy.backgroundSprite = [CCSprite spriteWithFile:@"dpad.png"];
        leftJoy.thumbSprite = [CCSprite spriteWithFile:@"joystick.png"];
        leftJoy.joystick = [[SneakyJoystick alloc] initWithRect:CGRectMake(0,0,128,128)];
        leftJoyStick = [leftJoy.joystick retain];
        [self addChild:leftJoy];

        character = [CCSprite spriteWithFile:@"player.jpg"];

        mainCharacter = character;
        [self addChild:mainCharacter];

        [self schedule:@selector(tick:)];

        [[CCDirector sharedDirector] setAnimationInterval:0.0000001f/10000.0f];

    }
    return self;
}

-(void)tick:(float)delta
{
    character.position = ccp(character.position.x + (leftJoyStick.velocity.x),
                             character.position.y + (leftJoyStick.velocity.y));

}

@end

Yep, that is just about it!