Package org.apache.lucene.document

Class ShapeField

java.lang.Object

org.apache.lucene.document.ShapeField

public final class ShapeField
extends java.lang.Object

A base shape utility class used for both LatLon (spherical) and XY (cartesian) shape fields.

Polygon's and Line's are decomposed into a triangular mesh using the Tessellator utility class. Each ShapeField.Triangle is encoded by this base class and indexed as a seven dimension multi-value field.

Finding all shapes that intersect a range (e.g., bounding box), or target shape, at search time is efficient.

This class defines the static methods for encoding the three vertices of a tessellated triangles as a seven dimension point. The coordinates are converted from double precision values into 32 bit integers so they are sortable at index time.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ShapeField.DecodedTriangle	Represents a encoded triangle using decodeTriangle(byte[], DecodedTriangle).
static class	ShapeField.QueryRelation	Query Relation Types
static class	ShapeField.Triangle	polygons are decomposed into tessellated triangles using Tessellator these triangles are encoded and inserted as separate indexed POINT fields

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static int	BYTES	vertex coordinates are encoded as 4 byte integers
private static int	MAXY_MINX_MINY_MAXX_Y_X
private static int	MAXY_MINX_MINY_X_Y_MAXX
private static int	MAXY_MINX_Y_X_MINY_MAXX
private static int	MINY_MINX_MAXY_MAXX_Y_X
private static int	MINY_MINX_Y_MAXX_MAXY_X
private static int	MINY_MINX_Y_X_MAXY_MAXX
protected static FieldType	TYPE	tessellated triangles are seven dimensions; the first four are the bounding box index dimensions
private static int	Y_MINX_MINY_MAXX_MAXY_X
private static int	Y_MINX_MINY_X_MAXY_MAXX

Constructor Summary

Constructors

Modifier	Constructor	Description
private	ShapeField()

Method Summary

Modifier and Type	Method	Description
static void	decodeTriangle(byte[] t, ShapeField.DecodedTriangle triangle)	Decode a triangle encoded by encodeTriangle(byte[], int, int, boolean, int, int, boolean, int, int, boolean).
static void	encodeTriangle(byte[] bytes, int aY, int aX, boolean ab, int bY, int bX, boolean bc, int cY, int cX, boolean ca)	A triangle is encoded using 6 points and an extra point with encoded information in three bits of how to reconstruct it.
private static void	resolveTriangleType(ShapeField.DecodedTriangle triangle)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BYTES

static final int BYTES

vertex coordinates are encoded as 4 byte integers

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Constant Field Values

TYPE

protected static final FieldType TYPE

tessellated triangles are seven dimensions; the first four are the bounding box index dimensions

MINY_MINX_MAXY_MAXX_Y_X

private static final int MINY_MINX_MAXY_MAXX_Y_X

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Constant Field Values

MINY_MINX_Y_X_MAXY_MAXX

private static final int MINY_MINX_Y_X_MAXY_MAXX

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Constant Field Values

MAXY_MINX_Y_X_MINY_MAXX

private static final int MAXY_MINX_Y_X_MINY_MAXX

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Constant Field Values

MAXY_MINX_MINY_MAXX_Y_X

private static final int MAXY_MINX_MINY_MAXX_Y_X

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Constant Field Values

Y_MINX_MINY_X_MAXY_MAXX

private static final int Y_MINX_MINY_X_MAXY_MAXX

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Constant Field Values

Y_MINX_MINY_MAXX_MAXY_X

private static final int Y_MINX_MINY_MAXX_MAXY_X

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Constant Field Values

MAXY_MINX_MINY_X_Y_MAXX

private static final int MAXY_MINX_MINY_X_Y_MAXX

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Constant Field Values

MINY_MINX_Y_MAXX_MAXY_X

private static final int MINY_MINX_Y_MAXX_MAXY_X

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Constant Field Values

Constructor Detail

ShapeField

private ShapeField()

Method Detail

encodeTriangle

public static void encodeTriangle(byte[] bytes,
                                  int aY,
                                  int aX,
                                  boolean ab,
                                  int bY,
                                  int bX,
                                  boolean bc,
                                  int cY,
                                  int cX,
                                  boolean ca)

A triangle is encoded using 6 points and an extra point with encoded information in three bits of how to reconstruct it. Triangles are encoded with CCW orientation and might be rotated to limit the number of possible reconstructions to 2^3. Reconstruction always happens from west to east.

decodeTriangle

public static void decodeTriangle(byte[] t,
                                  ShapeField.DecodedTriangle triangle)

Decode a triangle encoded by encodeTriangle(byte[], int, int, boolean, int, int, boolean, int, int, boolean).

resolveTriangleType

private static void resolveTriangleType(ShapeField.DecodedTriangle triangle)