ios - SpriteKit - 停止对象堆积

Question

我想知道我应该添加什么代码来阻止岩石堆积在屏幕底部并在休息(不移动)时将它们移除。

这是创建岩石的代码。如果您需要任何其他代码，请告诉我:)

-(void)addRock {

    SKSpriteNode *rock = [SKSpriteNode spriteNodeWithImageNamed:@"asteroid"];
    rock.position = CGPointMake ([self makeRandomXWBetween:0 and:self.size.width], self.size.height);
    rock.name = @"rock";
    rock.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:rock.size];
    rock.physicsBody.usesPreciseCollisionDetection = YES;
    rock.physicsBody.categoryBitMask = rockCategory;
    rock.physicsBody.contactTestBitMask = dodgerCategory;
    [self addChild:rock]; 
}

-(void)makeRocks {

    SKAction *makeRocks = [SKAction sequence: @[
                                                [SKAction performSelector:@selector(addRock) onTarget:self],
                                                [SKAction waitForDuration:0.3 withRange:0.0]
                                                ]];
    [self runAction: [SKAction repeatActionForever:makeRocks]];
}

在此先感谢您的帮助!

最好的问候，路易斯。

Answer 1

由于您希望岩石在静止时被移除，因此可以在它们的 velocity 属性为零时移除它们。

您可以在 -update 方法中进行检查。

-(void)update:(CFTimeInterval)currentTime {

    [self enumerateChildNodesWithName:@"rock" usingBlock:^(SKNode *node, BOOL *stop){

        if ((node.physicsBody.velocity.dx == 0) && (node.physicsBody.velocity.dy == 0) && (node.position.y < self.size.height)) {
            [node removeFromParent];
        }
    }];
}