Rotating a sprite when it is a Chipmunk body?

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Rotating a sprite when it is a Chipmunk body?

(3 posts) (3 voices)

Started 1 year ago by JJJohan2
Latest reply from habus

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JJJohan2
Member

Basically I have an issue that I can't resolve neither by trial and error or by searching for it.

My problem is, I want to set the direction of an object, a character in my little app, as he heads towards the center of the screen. How can I do that? I've tried rotating the sprite but this seems to do nothing. Basically, there are many instances of these objects so I can't simply use a CCNode tag and apply an action (as far as I know). I'm not sure what code should be provided here so I'll leave it up to any person brave enough to answer if they require any.

Posted 1 year ago #
mobilebros
Moderator
I think you're essentially trying to rotate a sprite and have the associated shape rotate with it?

subclass the sprite, hold a reference to the shape, and override the setRotation method
```
-(void) setRotation:(float)rot
{
    [super setRotation:rot];

    _cpBodySetAngle(shape->body, -CC_DEGREES_TO_RADIANS(rot));
}
```
By the way, theres a class in space manager called cpCCSprite that accomplishes this as well as position (independent of space manager, but dependent on cpCCNodeImpl).

http://code.google.com/p/chipmunk-spacemanager/
Posted 1 year ago #

habus
Member

Hi mobilebros,

I'm having a hard time trying to implement what you mention here. I'm using cocos2d 0.9 and spacemanager 0.0.7 (I guess) the one that came with cocos2d on Leopard.

On cpCCSprite.h I have:

/*! The shape we're connected to */
@property (readwrite,assign) cpShape *shape;

-(void)setRotation:(float)rot;    // I added this line to over write the method

and on the cpCCSprite.m file, the implementation:

-(void)setRotation:(float)rot
{
    [super setRotation:rot];

    //cpBodySetAngle(self.shape->body, -CC_DEGREES_TO_RADIANS(rot));

    self.shape->body->a = rot;      // attempt to access the variable.. not very successful
}

But no matters what I do it doesn't work :(. If I remove the self on self.shape it won't compile. Could you help me out to find what I'm doing wrong?

Rotating a sprite when it is a Chipmunk body?

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