org.h2gis.functions.spatial.earth

Class ST_Isovist

java.lang.Object

org.h2gis.api.AbstractFunction

org.h2gis.api.DeterministicScalarFunction

org.h2gis.functions.spatial.earth.ST_Isovist

All Implemented Interfaces:

org.h2gis.api.Function, org.h2gis.api.ScalarFunction

public class ST_Isovist
extends org.h2gis.api.DeterministicScalarFunction

ST_Isovist ST_Isovist takes LINESTRING(S) or POLYGON(S) as input and a maximum distance (spatial ref units). This function compute the visibility polygon obstructed by provided "walls". Provided segments will be enclosed by a circle defined by maximum distance parameter.

Author:

Nicolas Fortin, Ifsttar UMRAE

Field Summary

Fields inherited from interface org.h2gis.api.ScalarFunction

PROP_DETERMINISTIC, PROP_NOBUFFER

Fields inherited from interface org.h2gis.api.Function

PROP_NAME, PROP_REMARKS

Constructor Summary

Constructors

Constructor and Description
ST_Isovist()

Method Summary

Modifier and Type	Method and Description
String	getJavaStaticMethod()
static org.locationtech.jts.geom.Geometry	isovist(org.locationtech.jts.geom.Geometry viewPoint, org.locationtech.jts.geom.Geometry lineSegments, double maxDistance) This function compute the visibility polygon
static org.locationtech.jts.geom.Geometry	isovist(org.locationtech.jts.geom.Geometry viewPoint, org.locationtech.jts.geom.Geometry lineSegments, double maxDistance, double radBegin, double radSize) This function compute the visibility polygon

Methods inherited from class org.h2gis.api.AbstractFunction

addProperty, getProperty, removeProperty

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.h2gis.api.Function

getProperty

Constructor Detail

ST_Isovist

public ST_Isovist()

Method Detail

getJavaStaticMethod

public String getJavaStaticMethod()

isovist

public static org.locationtech.jts.geom.Geometry isovist(org.locationtech.jts.geom.Geometry viewPoint,
                                                         org.locationtech.jts.geom.Geometry lineSegments,
                                                         double maxDistance)
                                                  throws SQLException

This function compute the visibility polygon

Parameters:

viewPoint - Point instance, isovist location

lineSegments - Occlusion segments. Geometry collection or polygon or linestring

maxDistance - Maximum distance of view from viewPoint (spatial ref units)

Returns:

The visibility polygon

Throws:

SQLException - In case of wrong parameters

isovist

public static org.locationtech.jts.geom.Geometry isovist(org.locationtech.jts.geom.Geometry viewPoint,
                                                         org.locationtech.jts.geom.Geometry lineSegments,
                                                         double maxDistance,
                                                         double radBegin,
                                                         double radSize)
                                                  throws SQLException

This function compute the visibility polygon

Parameters:

viewPoint - Point instance, isovist location

lineSegments - Occlusion segments. Geometry collection or polygon or linestring

maxDistance - Maximum distance of view from viewPoint (spatial ref units)

radBegin - Constraint view angle start in radian

radSize - Constraint view angle size in radian

Returns:

The visibility polygon

Throws:

SQLException - In case of wrong parameters