Question

我已经制造了第二个球，但它落在了地板上。任何人都可以找出原因吗？我真的找不到另一件我需要复制或适应第一球所具有的第二球的东西。

这是我的代码：

#import "HelloWorldLayer.h"

@implementation HelloWorldLayer

+ (id)scene {

    CCScene *scene = [CCScene node];
    HelloWorldLayer *layer = [HelloWorldLayer node];
    [scene addChild:layer];
    return scene;

}

- (id)init {



    if ((self=[super init])) {

        CGSize winSize = [CCDirector sharedDirector].winSize;

        // Create sprite and add it to the layer
        _ball = [CCSprite spriteWithFile:@"ball.png" rect:CGRectMake(0, 0, 52, 52)];
        _ball.position = ccp(100, 300);
        [self addChild:_ball];

        _ball2 = [CCSprite spriteWithFile:@"ball.png" rect:CGRectMake(0, 0, 52, 52)];
        _ball2.position = ccp(300, 300);
        [self addChild:_ball2];

        // Create a world
        b2Vec2 gravity = b2Vec2(0.0f, -8.0f);
        _world = new b2World(gravity);


        // Create BALL 1 body and shape
        b2BodyDef ballBodyDef;
        ballBodyDef.type = b2_dynamicBody;
        ballBodyDef.position.Set(100/PTM_RATIO, 300/PTM_RATIO);
        ballBodyDef.userData = _ball;
        _body = _world->CreateBody(&ballBodyDef);

        b2CircleShape circle;
        circle.m_radius = 26.0/PTM_RATIO;

        b2FixtureDef ballShapeDef;
        ballShapeDef.shape = &circle;
        ballShapeDef.density = 2.0f;
        ballShapeDef.friction = 0.1f;
        ballShapeDef.restitution = 0.4f;
        _body->CreateFixture(&ballShapeDef);

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


        // Create BALL 2 body and shape
        b2BodyDef ballBodyDef2;
        ballBodyDef2.type = b2_dynamicBody;
        ballBodyDef2.position.Set(300/PTM_RATIO, 300/PTM_RATIO);
        ballBodyDef2.userData = _ball2;
        _body2 = _world->CreateBody(&ballBodyDef2);

        b2CircleShape circle2;
        circle2.m_radius = 26.0/PTM_RATIO;

        b2FixtureDef ballShapeDef2;
        ballShapeDef2.shape = &circle2;
        ballShapeDef2.density = 2.0f;
        ballShapeDef2.friction = 0.1f;
        ballShapeDef2.restitution = 0.4f;
        _body->CreateFixture(&ballShapeDef2);

        // Create edges around the entire screen
        b2BodyDef groundBodyDef;
        groundBodyDef.position.Set(0,0);

        b2Body *groundBody = _world->CreateBody(&groundBodyDef);
        b2EdgeShape groundEdge;
        b2FixtureDef boxShapeDef;
        boxShapeDef.shape = &groundEdge;

        //WALL DEFINITIONS
        //floor wall
        groundEdge.Set(b2Vec2(0,0), b2Vec2(winSize.width/PTM_RATIO, 0));
        groundBody->CreateFixture(&boxShapeDef);
        //roof wall
        groundEdge.Set(b2Vec2(0,0), b2Vec2(0,winSize.height/PTM_RATIO));
        groundBody->CreateFixture(&boxShapeDef);
        //left wall
        groundEdge.Set(b2Vec2(0, winSize.height/PTM_RATIO),
                       b2Vec2(winSize.width/PTM_RATIO, winSize.height/PTM_RATIO));
        groundBody->CreateFixture(&boxShapeDef);
        //right wall
        groundEdge.Set(b2Vec2(winSize.width/PTM_RATIO, winSize.height/PTM_RATIO),
                       b2Vec2(winSize.width/PTM_RATIO, 0));
        groundBody->CreateFixture(&boxShapeDef);


         //Do the kick every 5 seconds
         //[self schedule:@selector(kick) interval:5.0];

        [self setTouchEnabled:YES];

    }
    return self;

}

- (void)tick:(ccTime) dt {

    _world->Step(dt, 10, 10);
    for(b2Body *b = _world->GetBodyList(); b; b=b->GetNext()) {
        if (b->GetUserData() != NULL) {
            CCSprite *ballData = (CCSprite *)b->GetUserData();
            ballData.position = ccp(b->GetPosition().x * PTM_RATIO,
                                    b->GetPosition().y * PTM_RATIO);
            ballData.rotation = -1 * CC_RADIANS_TO_DEGREES(b->GetAngle());
        }
    }

}


- (void)dealloc {
    delete _world;
    _body = NULL;
    _world = NULL;
    [super dealloc];
}

@end

Answer 1

更改此

_body->CreateFixture(&ballShapeDef2);

到这个

_body2->CreateFixture(&ballShapeDef2);

为什么我的第二个球不能在我的cocos2d box2d项目中弹跳？

1 个答案: