Turn cost support in DijkstraOneToMany

I’m trying to create some distance (or weight) matrices. I’m currently using DijkstraOneToMany, and have created my own method (to avoid extracting a path):

public double calcWeight(int from, int to) {
    fromNode = from;
    endNode = findEndNode(from, to);
    return weights[endNode];

All’s working well - it creates a matrix for my country in about four hours.

However, I now want to add in turn costs - my expectation is that the path weight will now include a (customisable?) penalty for each turn/intersection along the route. However, I can’t seem to get anything different to the current results. That is, I get the same weights for the following (no turn costs)

encoder = new CarEncoder(5, 5, 0);
hopper = new GraphHopperOSM();
tMode = TraversalMode.NODE_BASED;
hopper.setEncodingManager(new EncodingManager(encoder));
Weighting weighting = new FastestWeighting(encoder);

algo = new DijkstraOneToMany(hopper.getGraphHopperStorage(), weighting, tMode));

and this (my attempt at turn costs) - only changed lines shown:

encoder = new CarEncoder(5, 5, 1);
weighting = hopper.createTurnWeighting(hopper.getGraphHopperStorage().getBaseGraph(), new FastestWeighting(encoder), tMode);

Does DijkstraOneToMany not support turn costs, or am I doing something wrong?

Ok, apparently turn costs aren’t supported with traversal mode NODE_BASED - it sneakily just reverts to the super weighting, without telling you. (@karussell, wouldn’t an exception be preferred to avoid misunderstandings like this?)

Setting to EDGE_BASED_2DIR seems to be doing something different … but now DijkstraOneToMany runs out of memory (even after bumping up to 16G or so):

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
	at java.util.Arrays.copyOf(Unknown Source)
	at com.graphhopper.apache.commons.collections.IntDoubleBinaryHeap.ensureCapacity(IntDoubleBinaryHeap.java:209)
	at com.graphhopper.apache.commons.collections.IntDoubleBinaryHeap.insert_(IntDoubleBinaryHeap.java:84)
	at com.graphhopper.routing.DijkstraOneToMany.findEndNode(DijkstraOneToMany.java:167)
	at com.datamine.twodegrees.dmatrix.WeightOnlyDijkstraOneToMany.calcWeight(WeightOnlyDijkstraOneToMany.java:16)
	at com.datamine.twodegrees.dmatrix.DistanceMatrix.createAndWrite(DistanceMatrix.java:105)
	at com.datamine.twodegrees.dmatrix.DistanceMatrix.createOrLoad(DistanceMatrix.java:57)
	at com.datamine.twodegrees.dmatrix.DistanceMatrixMain.main(DistanceMatrixMain.java:31)

@karussell - not sure if this is a bug or because I’m not meant to use it DijkstraOneToMany with turn costs. I’ve had a quick look, and even though I’ve got under a million nodes, the heap balloons out to billions (hence the memory issue). It looks like the weights are coming out as infinite, and I’m guessing that’s mucking with the heap.

DijkstraOneToMany does not support edge based traversal. But have a look into a recent pull request: https://github.com/graphhopper/graphhopper/pull/912

Where one part of the change is a hopefully proper edge based implementation.

@karussell, wouldn’t an exception be preferred to avoid misunderstandings like this?


Thanks @karussell - PR submitted.