C++ vector_vs::erase_swap方法代码示例

void	CRailTrack::Update()
{
	mNextUpdateTime = level.time + mNextUpdateDelay;


	// Now, Attempt To Add A Number Of Movers To The Track
	//-----------------------------------------------------
	int		attempt;
	int		startCol;
	int		stopCol;
	int		atCol;
	int		testColIndex;

	for (attempt=0; attempt<mNumMoversPerRow; attempt++)
	{
		// Randomly Select A Mover And Test To See If It Is Active
		//---------------------------------------------------------
		CRailMover*	mover = mMovers[Q_irand(0, mMovers.size()-1)];
		if (mover->Active())
		{
			continue;
		}

		// Don't Spawn Until Start Time Has Expired
		//------------------------------------------
		if (level.time < ((mover->mLane)?(mover->mLane->mStartTime):(mStartTime)))
		{
			continue;
		}

		// If Center Locked, Stop Spawning Center Track Movers
		//-----------------------------------------------------
		if (mover->mCenter && mCenterLocked)
		{
			continue;
		}
	

		// Restrict It To A Lane
		//-----------------------
		if (mover->mLane)
		{
			startCol	= mover->mLane->mMinCol;
			stopCol		= mover->mLane->mMaxCol+1;
		}

		// Or Let It Go Anywhere On The Track
		//------------------------------------
		else
		{
			startCol	= 0;
			stopCol		= mCols;
		}
		stopCol -= (mover->mCols-1);


		// If The Mover Is Too Big To Fit In The Lane, Go On To Next Attempt
		//-------------------------------------------------------------------
		if (stopCol<=startCol)
		{
			assert(0);	// Should Not Happen
			continue;
		}

		// Force It To Center
		//--------------------
		if (mover->mCenter && stopCol!=(startCol+1))
		{
			startCol	= ((mCols/2) - (mover->mCols/2));
			stopCol		= startCol+1;
		}


		// Construct A List Of Columns To Test For Insertion
		//---------------------------------------------------
		mTestCols.clear();
		for (int i=startCol; i<stopCol; i++)
		{
			mTestCols.push_back(i);
		}

		// Now Try All The Cols To See If The Building Can Fit
		//-----------------------------------------------------
		while (!mTestCols.empty())
		{
			// Randomly Pick A Column, Then Remove It From The Vector
			//--------------------------------------------------------
			testColIndex = Q_irand(0, mTestCols.size()-1);
			atCol = mTestCols[testColIndex];
			mTestCols.erase_swap(testColIndex);

			if (TestMoverInCells(mover, atCol))
			{
				// Ok, We've Found A Safe Column To Insert This Mover
				//----------------------------------------------------
				InsertMoverInCells(mover, atCol);

				// Now Transport The Actual Mover Entity Into Position, Link It & Send It Off
				//----------------------------------------------------------------------------
				CVec3	StartPos(mGridBottomLeftCorner);
//.........这里部分代码省略.........

////////////////////////////////////////////////////////////////////////////////////////
// Update The Packs, Delete Dead Leaders, Join / Split Packs, Find MY Leader
////////////////////////////////////////////////////////////////////////////////////////
gentity_t* NPC_AnimalUpdateLeader(void)
{
	// Find The Closest Pack Leader, Not Counting Myself
	//---------------------------------------------------
	gentity_t*	closestLeader = 0;
	float		closestDist = 0;
	int			myLeaderNum = 0;
	
	for (int i=0; i<mPacks.size(); i++)
	{
		// Dump Dead Leaders
		//-------------------
		if (mPacks[i]==0 || mPacks[i]->health<=0)
		{
			if (mPacks[i]==NPC->client->leader)
			{
				NPC->client->leader = 0;
			}

			mPacks.erase_swap(i);

			if (i>=mPacks.size())
			{
				closestLeader = 0;
				break;
			}
		}

		// Don't Count Self
		//------------------
		if (mPacks[i]==NPC)
		{
			myLeaderNum = i;
			continue;
		}

		float	Dist = Distance(mPacks[i]->currentOrigin, NPC->currentOrigin);
		if (!closestLeader || Dist<closestDist)
		{
			closestDist = Dist;
			closestLeader = mPacks[i];
		}
	}

	// In Joining Distance?
	//----------------------
	if (closestLeader && closestDist<JOIN_PACK_DISTANCE)
	{
		// Am I Already A Leader?
		//------------------------
		if (NPC->client->leader==NPC)
		{
			mPacks.erase_swap(myLeaderNum);		// Erase Myself From The Leader List
		}

		// Join The Pack!
		//----------------
		NPC->client->leader = closestLeader;
	}


	// Do I Have A Leader?
	//---------------------
	if (NPC->client->leader)
	{
		// AM I A Leader?
		//----------------
		if (NPC->client->leader!=NPC)
		{
			// If Our Leader Is Dead, Clear Him Out

			if ( NPC->client->leader->health<=0 || NPC->client->leader->inuse == 0)
			{
				NPC->client->leader = 0;
			}
			
			// If My Leader Isn't His Own Leader, Then, Use His Leader
			//---------------------------------------------------------
			else if (NPC->client->leader->client->leader!=NPC->client->leader)
			{
				// Eh.  Can this get more confusing?
				NPC->client->leader = NPC->client->leader->client->leader;
			}

			// If Our Leader Is Too Far Away, Clear Him Out
			//------------------------------------------------------
			else if ( Distance(NPC->client->leader->currentOrigin, NPC->currentOrigin)>LEAVE_PACK_DISTANCE)
			{
				NPC->client->leader = 0;
			}
		}

	}

	// If We Couldn't Find A Leader, Then Become One
	//-----------------------------------------------
	else if (!mPacks.full())
//.........这里部分代码省略.........