Package org.geotools.renderer.crs

Class WrappingProjectionHandler

Object

ProjectionHandler

WrappingProjectionHandler

public class WrappingProjectionHandler
extends ProjectionHandler

A ProjectionHandler for projections that do warp in the East/West direction, it will replicate the geometries generating a Google Maps like effect

Author:

Andrea Aime - OpenGeo

Field Summary

Fields

Modifier and Type	Field	Description
static double	DATELINE_PROXIMITY_TOLERANCE	The tolerance to consider a geometry without touching both datelines.
static String	DATELINE_WRAPPING_CHECK_ENABLED
protected static String	PREFLIPPED_OBJECT	The user data key to indicate that the geometry was pre-flipped

Fields inherited from class ProjectionHandler

ADVANCED_PROJECTION_DENSIFY, datelineX, DEFAULT_DENSIFICATION_LIMIT, DENSIFICATION_LIMIT_KEY, densify, EPS, geometryCRS, LOGGER, noReprojection, queryAcrossDateline, renderingEnvelope, sourceAxisOrder, sourceCRS, targetAxisOrder, targetCRS, targetHalfCircle, validaAreaTester, validArea, validAreaBounds

Constructor Summary

Constructors

Constructor	Description
WrappingProjectionHandler(ReferencedEnvelope renderingEnvelope, ReferencedEnvelope validArea, CoordinateReferenceSystem sourceCrs, double centralMeridian, int maxWraps)	Provides the strategy with the area we want to render and its CRS (the SPI lookup will do this step)

Method Summary

Modifier and Type	Method	Description
boolean	isDatelineWrappingCheckEnabled()
Geometry	postProcess(MathTransform mt, Geometry geometry)	Processes the geometry already projected to the target SRS.
Geometry	preProcess(Geometry geometry)	Pre processes the geometry, e.g. cuts it, splits it, etc. in its native srs.
boolean	requiresProcessing(Geometry geometry)	Returns true if the geometry needs special handling
void	setDatelineWrappingCheckEnabled(boolean datelineWrappingCheckEnabled)	Enables the check using the "half world" heuristic on the input geometries, if larger it assumes they spanned the dateline.
void	setProjectionParameters(Map<String,Object> projectionParameters)	Set one of the supported projection parameters: - datelineWrappingCheckEnabled (boolean) if false disables the heuristic for dateline wrapping check (true by default)

Methods inherited from class ProjectionHandler

accumulateTransforms, addGeometries, computeDatelineX, concatenateTransforms, densify, getProjectedEnvelope, getQueryEnvelopes, getRenderingEnvelope, getRenderingTransform, getSourceCRS, getSourceEnvelopes, getValidArea, getValidAreaBounds, intersect, mergeEnvelopes, reprojectEnvelopes, setCentralMeridian, transformEnvelope

Methods inherited from class Object

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

Field Detail

PREFLIPPED_OBJECT

protected static final String PREFLIPPED_OBJECT

The user data key to indicate that the geometry was pre-flipped

See Also:

Constant Field Values

DATELINE_PROXIMITY_TOLERANCE

public static final double DATELINE_PROXIMITY_TOLERANCE

The tolerance to consider a geometry without touching both datelines. Derived using trial and error. Any smaller and Antarctica-like polygons are incorrectly tagged.

See Also:

Constant Field Values

DATELINE_WRAPPING_CHECK_ENABLED

public static final String DATELINE_WRAPPING_CHECK_ENABLED

See Also:

Constant Field Values

Constructor Detail

WrappingProjectionHandler

public WrappingProjectionHandler(ReferencedEnvelope renderingEnvelope,
                                 ReferencedEnvelope validArea,
                                 CoordinateReferenceSystem sourceCrs,
                                 double centralMeridian,
                                 int maxWraps)
                          throws FactoryException

Provides the strategy with the area we want to render and its CRS (the SPI lookup will do this step)

Throws:

FactoryException

Method Detail

setProjectionParameters

public void setProjectionParameters(Map<String,Object> projectionParameters)

Set one of the supported projection parameters: - datelineWrappingCheckEnabled (boolean) if false disables the heuristic for dateline wrapping check (true by default)

Overrides:

setProjectionParameters in class ProjectionHandler

preProcess

public Geometry preProcess(Geometry geometry)
                    throws TransformException,
                           FactoryException

Description copied from class: ProjectionHandler

Pre processes the geometry, e.g. cuts it, splits it, etc. in its native srs. May return null if the geometry is not to be drawn

Overrides:

preProcess in class ProjectionHandler

Throws:

TransformException

FactoryException

postProcess

public Geometry postProcess(MathTransform mt,
                            Geometry geometry)

Description copied from class: ProjectionHandler

Processes the geometry already projected to the target SRS. May return null if the geometry is not to be drawn.

Overrides:

postProcess in class ProjectionHandler

Parameters:

mt - optional reverse transformation to facilitate unwrapping

requiresProcessing

public boolean requiresProcessing(Geometry geometry)

Description copied from class: ProjectionHandler

Returns true if the geometry needs special handling

Overrides:

requiresProcessing in class ProjectionHandler

isDatelineWrappingCheckEnabled

public boolean isDatelineWrappingCheckEnabled()

setDatelineWrappingCheckEnabled

public void setDatelineWrappingCheckEnabled(boolean datelineWrappingCheckEnabled)

Enables the check using the "half world" heuristic on the input geometries, if larger it assumes they spanned the dateline. Enabled by default