Examples with SparseMatrixZSampleGrid org.opentripplanner.common.geometry.SparseMatrixZSampleGrid used on opensource projects

Example 1 with SparseMatrixZSampleGrid

use of org.opentripplanner.common.geometry.SparseMatrixZSampleGrid in project OpenTripPlanner by opentripplanner.

the class SampleGridRenderer method getSampleGrid.

/**
 * @param spgRequest
 * @param sptRequest
 * @return
 */
public ZSampleGrid<WTWD> getSampleGrid(SampleGridRequest spgRequest, RoutingRequest sptRequest) {
    final double offRoadDistanceMeters = spgRequest.offRoadDistanceMeters;
    // m/s, off-road walk speed
    final double offRoadWalkSpeedMps = 1.00;
    // 1. Compute the Shortest Path Tree.
    long t0 = System.currentTimeMillis();
    long tOvershot = (long) (2 * offRoadDistanceMeters / offRoadWalkSpeedMps);
    sptRequest.worstTime = (sptRequest.dateTime + (sptRequest.arriveBy ? -spgRequest.maxTimeSec - tOvershot : spgRequest.maxTimeSec + tOvershot));
    sptRequest.batch = (true);
    sptRequest.setRoutingContext(graph);
    // TODO swap in different state dominance logic (earliest arrival, pareto, etc.)
    final ShortestPathTree spt = new AStar().getShortestPathTree(sptRequest);
    // 3. Create a sample grid based on the SPT.
    long t1 = System.currentTimeMillis();
    Coordinate coordinateOrigin = spgRequest.coordinateOrigin;
    if (coordinateOrigin == null)
        coordinateOrigin = sptRequest.from.getCoordinate();
    final double gridSizeMeters = spgRequest.precisionMeters;
    final double cosLat = FastMath.cos(toRadians(coordinateOrigin.y));
    double dY = Math.toDegrees(gridSizeMeters / SphericalDistanceLibrary.RADIUS_OF_EARTH_IN_M);
    double dX = dY / cosLat;
    SparseMatrixZSampleGrid<WTWD> sampleGrid = new SparseMatrixZSampleGrid<WTWD>(16, spt.getVertexCount(), dX, dY, coordinateOrigin);
    sampleSPT(spt, sampleGrid, gridSizeMeters, offRoadDistanceMeters, offRoadWalkSpeedMps, sptRequest.getMaxWalkDistance(), spgRequest.maxTimeSec, cosLat);
    sptRequest.cleanup();
    long t2 = System.currentTimeMillis();
    LOG.info("Computed SPT in {}msec, {}msec for sampling ({} msec total)", (int) (t1 - t0), (int) (t2 - t1), (int) (t2 - t0));
    return sampleGrid;
}

Example 2 with SparseMatrixZSampleGrid

use of org.opentripplanner.common.geometry.SparseMatrixZSampleGrid in project OpenTripPlanner by opentripplanner.

the class IsochroneGenerator method makeGrid.

/**
 * Make a ZSampleGrid from a PointSet and a parallel array of travel times for that PointSet.
 * Those times could come from a ResultSetWithTimes or directly from a PropagatedTimesStore, which has one
 * such array for each of min, avg, and max travel time over the departure time window it represents.
 * If your PointSet is dense enough (e.g. every block in a city) then this should yield a decent surface and
 * isochrones.
 * FIXME code duplication, this is ripped off from TimeSurface and should probably replace the version there as it is more generic.
 * @param walkSpeed the walk speed in meters per second
 * @return a grid suitable for making isochrones, based on an arbitrary PointSet and times to reach all those points.
 */
public static ZSampleGrid makeGrid(PointSet pointSet, int[] times, double walkSpeed) {
    // offroad walk distance roughly grid size
    final double D0 = WALK_DISTANCE_GRID_SIZE_RATIO * GRID_SIZE_METERS;
    // off-road walk speed in m/sec
    final double V0 = walkSpeed;
    // Use the first feature as the center of the projection
    Coordinate coordinateOrigin = pointSet.getCoordinate(0);
    final double cosLat = FastMath.cos(toRadians(coordinateOrigin.y));
    double dY = Math.toDegrees(GRID_SIZE_METERS / SphericalDistanceLibrary.RADIUS_OF_EARTH_IN_M);
    double dX = dY / cosLat;
    ZSampleGrid grid = new SparseMatrixZSampleGrid<WTWD>(16, times.length, dX, dY, coordinateOrigin);
    AccumulativeGridSampler.AccumulativeMetric<WTWD> metric = new SampleGridRenderer.WTWDAccumulativeMetric(cosLat, D0, V0, GRID_SIZE_METERS);
    AccumulativeGridSampler<WTWD> sampler = new AccumulativeGridSampler<>(grid, metric);
    // Iterate over every point in this PointSet, adding it to the ZSampleGrid
    for (int p = 0; p < times.length; p++) {
        int time = times[p];
        WTWD z = new WTWD();
        z.w = 1.0;
        z.d = 0.0;
        z.wTime = time;
        // unused
        z.wBoardings = 0;
        // unused
        z.wWalkDist = 0;
        sampler.addSamplingPoint(pointSet.getCoordinate(p), z, V0);
    }
    sampler.close();
    return grid;
}