Как перемещать камеру в пределах границы в cocos2d Box2D

Question

-(void)moveCamera:(CGpoint)resultVector { 
float centerX, centerY, centerZ; 
float eyeX, eyeY, eyeZ; 

[self.camera centerX:&centerX centerY=&centerY centerZ=&centerZ]; 
[self.camera eyeX:&eyeX eyeY:&eyeY eyeZ:&eyeZ]; 

float newX = (resultVector.x - actorOriginalPosition.x) + (actorOriginalPosition.x - screenSize.width/2); 
float newY = (resultVector.y - actorOriginalPosition.y) + (actorOriginalPosition.y - screenSize.height/2); 

[self.camera setCenterX:newX centerY=newY centerZ:-150.0f]; 
[self.camera setEyeX:newX eyeY=newY eyeZ:eyeZ]; 

} 

Здесь resultVector является актер currentPosition

Answer 1

в функции обновления:

CGPoint direction = [self getPoint:myBody->GetPosition()]; 
[self setPosition:direction]; 


- (CGPoint)getPoint:(b2Vec2)vec 
{ 
    CGSize screen = [[CCDirector sharedDirector] winSize]; 

    float x = vec.x * PTM_RATIO; 
    float y = vec.y * PTM_RATIO; 

    x = MAX(x, screen.width/2); 
    y = MAX(y, screen.height/2); 

    float _x = area.width - (screen.width/2); 
    float _y = area.height - (screen.height/2); 

    x = MIN(x, _x); 
    y = MIN(y, _y); 

    CGPoint goodPoint = ccp(x,y); 

    CGPoint centerOfScreen = ccp(screen.width/2, screen.height/2); 
    CGPoint difference = ccpSub(centerOfScreen, goodPoint); 

    return difference; 
}