[Geotools-gt2-users] Perfomace problem while calculating intersection

[serega_sh <ser...@gm...>]

Hi, I'm trying to increase perfomance for intersection calculation.
Right now I need to calculate intersection of geometry figures of two sets:
circles and sectors.
It takes 426 seconds to calculate 68.000.000 intersections. It's toooo long.

Here is my code for getting GeometryShapeFactory:
I've used: numPoints=64
PrecisionModel = Fixed, scale=100 (mantissa length==2)
*public final class GeometricShapeFactoryThreadLocalBuilder {

    private static final int MANTISSA_LENGTH = 100;

    private GeometricShapeFactoryThreadLocalBuilder(){}

    public static ThreadLocal<GeometricShapeFactory> buildThreadLocal(){

        return new ThreadLocal<GeometricShapeFactory>(){

            public GeometricShapeFactory initialValue() {
                PrecisionModel fixedPrecisionModel = new
PrecisionModel(MANTISSA_LENGTH);
                return new GeometricShapeFactory(new
GeometryFactory(fixedPrecisionModel));
            }
         };
    }
}*

Here is my code to create Geometry figures:

*public final class GeometryBuilder {

    private static final int DIAMETER_MULTIPLIER = 2;
    private static final int TURN_LEFT = 90;    //We should start to roll to
the right from "North"/"Up"/12 o'clock

    private static final ThreadLocal<GeometricShapeFactory> SHAPE_FACTORY =
                                       
GeometricShapeFactoryThreadLocalBuilder.buildThreadLocal();
    private static final Integer DEFAULT_NUM_POINTS = 100;

    private GeometryBuilder(){}


   private static Circle buildCirlce(GeometryInfo geometryInfo, SpatialCoord
spatialCoordRelativeCenter){
       
SHAPE_FACTORY.get().setCentre(GeometryUtil.toCoordinate(geometryInfo.getSpatialCoord(),
spatialCoordRelativeCenter));
       
SHAPE_FACTORY.get().setNumPoints(returnDefaultIfNull(geometryInfo.getNumPoints(),
DEFAULT_NUM_POINTS));
        SHAPE_FACTORY.get().setSize(geometryInfo.getRadius().getMeters() *
DIAMETER_MULTIPLIER);
        return new Circle(SHAPE_FACTORY.get().createEllipse());
    }


    private static Sector buildSector(GeometryInfo geometryInfo,
SpatialCoord spatialCoordRelativeCenter){
       
SHAPE_FACTORY.get().setCentre(GeometryUtil.toCoordinate(geometryInfo.getSpatialCoord(),
spatialCoordRelativeCenter));
       
SHAPE_FACTORY.get().setNumPoints(returnDefaultIfNull(geometryInfo.getNumPoints(),
DEFAULT_NUM_POINTS));
        SHAPE_FACTORY.get().setSize(geometryInfo.getRadius().getMeters() *
DIAMETER_MULTIPLIER);
        return new Sector(SHAPE_FACTORY.get()
                   
.createArcPolygon(-toRadians(geometryInfo.getEndAngle().getDegrees() -
TURN_LEFT), toRadians(geometryInfo.getAngleWidth().getDegrees())));
    }
}*

Is there any possiblity to significantly increase perfomance? 
circles and sectors are presented as polygons described with 64 points. Is
there any way to perfom a hack: use real circles to describe geometry? It's
much cheaper to calculate intersection between cicles/sectors than polygons.




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