游戏实体：处理碰撞

for(int i = 0 ; i < totalEntities ; ++i)
 for(int j = i+1 ; j < totalEntities ; ++j)
 {  
  CollisionInfo info;
  if( CheckCollision(entities[i], entities[j], info) )
  {
     // Okay, what we should do? I suggest two solutions

     // 1. simple one
     entities[i].OnCollide(info);
     entities[j].OnCollide(info);

     // 2. event-or-message driven system
     EventManager::Instance()->SendEvent(COLLISION_EVENT, info)
  }
}

event-or-message system