Hi,
thanks a lot Michaël and Larry.
To limit the (inner) iteration through the features of layer b to those
features which envelopes intersect the envelope of layer a-feature
speeds up things a lot (approx. factor 120!).
The methods
com.vividsolutions.jump.feature.FeatureCollectionWrapper.query() and
com.vividsolutions.jump.feature.IndexedFeatureCollection.query() seem to
work the same way, at least there is no difference in the performance
with my data.
By the way:
com.vividsolutions.jts.geom.Geometry.intersects(Geometry geom) is less
expensive than
com.vividsolutions.jts.geom.Geometry.intersection(Geometry geom):
To replace
dblAreaIntersectionTemp+=featureB.getGeometry().intersection(featureA.getGeometry()).getArea();
with
if (featureB.getGeometry().intersects(featureA.getGeometry())) {
dblAreaIntersectionTemp+=featureB.getGeometry().intersection(featureA.getGeometry()).getArea();
}
in the inner loop speeds up things twice (even though both methods,
intersects AND intersection are applied to the intersecting geometries)!
Regards,
Nils
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