正确收集子弹的垃圾

Question

所以我正在为我正在开发的游戏使用简单的子弹系统，但我想知道从阵列和屏幕中移除子弹的最佳方法是什么，这样它就不会占用帧速率和内存？

-(void)spinTapped
{     
        [self.character stopAllActions];
        [self.character runAction:self.gunAction];
        isRunning = NO;
        CCSprite *bullet = [CCSprite spriteWithFile:@"rwby_bullet.png"];
        bullet.position = ccp(self.character.position.x , self.character.position.y + 15);
        [bullet setScale:2];
        if (isRight) {
            bullet.tag = 10;
        }
        else {
            bullet.tag = -10;
        }
        [bullets addObject:bullet];
        [self addChild:bullet z:-1];

}

然后在更新中：

for(CCSprite *bullet in bullets)
    {
        CGPoint bulletPosition = ccp(bullet.position.x , bullet.position.y);
        CGPoint B_tilePosition = [self tileCoorForPosition:bulletPosition];
        bullet.position = ccp(bullet.position.x + bullet.tag , bullet.position.y);

        NSMutableArray *emptySpace = [[NSMutableArray alloc] initWithCapacity:10000];
        [emptySpace addObject:[NSNumber numberWithInt:0]];

        @try {
            bullet_GID = [self.background tileGIDAt:B_tilePosition];
        }
        @catch (NSException *exception) {
            bullet_GID = 535677655;
        }
        @finally {

        }
        if(bullet_GID == 535677655)
        {
            [bullet setVisible:NO];
          //  [bullets removeObject:bullet];

        }
        else if(bullet_GID)
        {
            [bullet setVisible:NO];
          //  [bullets removeObject:bullet];
        }
    }

[bullets removeObject:bullet] 会导致应用程序在一颗子弹击中瓷砖而另一颗子弹在屏幕上时崩溃（我认为是问题所在）。那么什么才是正确的去除子弹的方法呢？

Answer 1

崩溃可能是因为您试图在“迭代数组”时从子弹数组中删除子弹对象：无法在迭代数组时修改它。所以，我建议你做类似的事情

NSMutableArray *bulletsToRemove = [NSMutableArray array];

for (CCSprite *bullet in bullets) {
   // your logic 
   if('should remove bullet') {
       [bulletsToRemove addObject:bullet];
   }
}

// now iterate the bullets to remove array, and remove safely from
// the bullets array

for (CCSprite *bulletToRemove in bulletsToRemove) {
    [bullets removeObject:bulletToRemove];
}