Function addIncomingNeighbors

src/procedures/proc_ss_paths.c:354–382

}

static void addIncomingNeighbors
(
	SingleSourceCtx *ctx,
	LevelConnection *frontier,
	uint32_t depth
) {
	EntityID frontierId = INVALID_ENTITY_ID;
	if(depth > 1) frontierId = ENTITY_GET_ID(&frontier->edge);

	// Get frontier neighbors.
	for(int i = 0; i < ctx->relationCount; i++) {
		Graph_GetNodeEdges(ctx->g, &frontier->node, GRAPH_EDGE_DIR_INCOMING, ctx->relationIDs[i], &ctx->neighbors);
	}

	// Add unvisited neighbors to next level.
	uint32_t neighborsCount = array_len(ctx->neighbors);

	_SingleSourceCtx_EnsureLevelArrayCap(ctx, depth, neighborsCount);
	for(uint32_t i = 0; i < neighborsCount; i++) {
		// Don't follow the frontier edge again.
		if(frontierId == ENTITY_GET_ID(ctx->neighbors + i)) continue;
		// Set the neighbor by following the edge in the correct directoin.
		Node neighbor = GE_NEW_NODE();
		Graph_GetNode(ctx->g, Edge_GetSrcNodeID(ctx->neighbors + i), &neighbor);
		// Add the node and edge to the frontier.
		_SingleSourceCtx_AddConnectionToLevel(ctx, depth, &neighbor, (ctx->neighbors + i));
	}
	array_clear(ctx->neighbors);
}

// traverse from the frontier node in the specified direction and add all encountered nodes and edges.
static void addNeighbors