Function SearchLOT_BFS

TombEngine/Game/control/box.cpp:1772–1853

* @brief Core breadth-first search for pathfinding through boxes. * * This function expands the search from the current Head box to all connected boxes. * It builds a "flow field" where each box's exitBox points toward the target. * * ALGORITHM: * 1. Take the box at Head of the queue. * 2. For each overlapping (connected) box: * a. Check zone compatibility (skip if different zone, unles

 * @return true if more boxes remain to expand, false if search exhausted.
 */
bool SearchLOT_BFS(LOTInfo* LOT, int depth)
{
	auto& zone = g_Level.Zones[(int)LOT->Zone][(int)FlipStatus];

	for (int i = 0; i < depth; i++)
	{
		// Search exhausted - no more boxes to expand.
		if (LOT->Head == NO_VALUE)
		{
			LOT->Tail = NO_VALUE;
			return false;
		}

		auto* node = &LOT->Node[LOT->Head];

		int index = g_Level.PathfindingBoxes[LOT->Head].overlapIndex;
		int searchZone = zone[LOT->Head];

		bool done = false;

		// Iterate through all boxes that overlap with current box.
		if (index >= 0)
		{
			do
			{
				int boxNumber = g_Level.Overlaps[index].box;
				int flags = g_Level.Overlaps[index].flags;

				index++;

				if (flags & OVERLAP_END_BIT)
					done = true;

				if (!CanExpandToBox(LOT, LOT->Head, boxNumber, flags, searchZone, zone))
					continue;

				// SEARCH STATE: Check if we've already visited this box.
				auto* expand = &LOT->Node[boxNumber];
				if ((node->searchNumber & SEARCH_NUMBER) < (expand->searchNumber & SEARCH_NUMBER))
					continue;

				// Handle blocked path propagation.
				if (node->searchNumber & SEARCH_BLOCKED)
				{
					if ((node->searchNumber & SEARCH_NUMBER) == (expand->searchNumber & SEARCH_NUMBER))
						continue;

					expand->searchNumber = node->searchNumber;
				}
				else
				{
					if ((node->searchNumber & SEARCH_NUMBER) == (expand->searchNumber & SEARCH_NUMBER) && !(expand->searchNumber & SEARCH_BLOCKED))
						continue;

					// Mark blocked boxes but still allow traversal through them.
					if (g_Level.PathfindingBoxes[boxNumber].flags & LOT->BlockMask)
					{
						expand->searchNumber = node->searchNumber | SEARCH_BLOCKED;