Using CCSprites in Cocos2d

Question

I was wondering if anyone out there knows how I would attache a CCSprite to a cpConstraint and have it update with the physics. Here is my code:

upper = [game.spaceManager addPolyAt:cpv(70,195) mass:300 rotation:0 numPoints:6 points:cpv(2,12), cpv(28,8), cpv(33,0), cpv(36,-10), cpv(-33,-10), cpv(-20,8)];
upper->collision_type = kTireCollisionType;

cpShape *lower = [game.spaceManager addPolyAt:cpv(70,125) mass:300 rotation:0 numPoints:7 points:cpv(34,8), cpv(31,0), cpv(25,-9), cpv(7,-13), cpv(-20,-8), cpv(-30,0), cpv(-35,8)];
lower->collision_type = kTireCollisionType;

//HIT POINT
cpShape *sensor = [game.spaceManager addCircleAt:cpv(70,160) mass:10 radius:10];
sensor->sensor = YES;
sensor->collision_type = kScoreCollisionType;

cpShape *sensor2 = [game.spaceManager addCircleAt:cpv(70, 160) mass:10 radius:10];
sensor2->sensor = YES;

//Combine them into one body!
[game.spaceManager combineShapes:upper, lower, sensor, sensor2, nil];

//The "rope"
cpVect a1 = cpv(0,30);      //Local coordinates of tire
cpVect a2 = cpv(70,320);    //World coordinates (staticBody is at (0,0))

//calculate the length of the rope
float max = cpvdist(cpBodyLocal2World(upper->body, a1), a2);
cpConstraint *rope = [game.spaceManager addSlideToBody:upper->body fromBody:game.spaceManager.staticBody toBodyAnchor:a1 fromBodyAnchor:a2 minLength:1 maxLength:max];

cpConstraintNode *ropeNode = [cpConstraintNode nodeWithConstraint:rope];
ropeNode.color = ccBLUE;
[game addChild:ropeNode];

//Attach a sprite to the sensor, lucky for us it's exactly in the center
//of the tire... otherwise this wouldn't work
[game addChild:[super initWithShape:sensor file:@"TractorTireFront.png"] z:3];
[game addChild:[cpCCSprite spriteWithShape:sensor2 file:@"TractorTireBack.png"] z:1];

ivGame = game;

//Free the shape when we are released
self.spaceManager = game.spaceManager;
self.autoFreeShape = YES;

[self schedule:@selector(step:) interval:.1];

return self;

This is the code for the init method. I have a tire on the screen and as you can see there is a cpConstraint acting as a rope which is hanging from the top of the screen and attached to the top of the tire. I am wanting to somehow attach a CCSprite to this constraint and have it update with the swinging of the tire or if there is another way to use a CCSprite and have it update with the swinging of the tire.

I am using cocos2d + spaceManager. I have heard people say to just use a CCSprite and update it with the tires movements, but I am not familiar enough with cocos2d or spaceManger to accomplish that, so if anyone has some code snippets or a tutorial showing me how I could go about this I would very much appreciate it.

might want to separate this into smaller questions, I think a lot of people are overwhelmed by this posts size... Just sayin' — tallen11, Apr 24 '11 at 18:36

score 0 · Accepted Answer · answered Aug 29 '12 at 08:41

I don't know chipmunk but what you would put in your tick method is

-(void) tick() {

// not sure how you get position in chipmunk, somehow convert it to cgPoint
CGPoint * p = ccp(cpConstraint->position.x, cpConstraint->position.y);

//find out the offset of the tire compared to the cpConstraint then add it to p

p = ccp(p.x + offset.x, p.y + offset.y);

//assign it to your CCSprite

sprite.position = p;

}

to initialize the CCSprite

CCSprite * s = [CCSprite spritreWithFile:"picture.png"];

//add to CCLayer with is self here

[self addChild:s];

Using CCSprites in Cocos2d

1 Answers1