Package org.geotools.renderer.label

Class LabelIndex

Object

LabelIndex

public class LabelIndex
extends Object

Stores label envelopes and detects interference by overlap or proximity.

Backed by LabelQuadtree for O(log n) spatial pruning with true early-exit on first hit. Pass margin large enough to contain any label that may be positioned outside the display area (e.g. with partialsEnabled).

Author:

Andrea Aime

Constructor Summary

Constructors

Constructor	Description
LabelIndex(Rectangle displayArea, int margin)

Method Summary

Modifier and Type	Method	Description
void	addLabel(LabelCacheItem item, Rectangle2D bounds)	Adds a label into the index.
boolean	labelsWithinDistance(Rectangle2D bounds, double distance)	Returns true if any label in the index is within distance of bounds.
void	reserveArea(List<Rectangle2D> reserved)	Reserves the areas indicated by these rectangles.

Methods inherited from class Object

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

Constructor Details

LabelIndex

public LabelIndex(Rectangle displayArea,
 int margin)

Parameters:

displayArea - rendering area in screen coordinates

margin - extra space beyond displayArea to accommodate labels outside the display area

Method Details

labelsWithinDistance

public boolean labelsWithinDistance(Rectangle2D bounds,
 double distance)

Returns true if any label in the index is within distance of bounds. The bounds are expanded by the distance (no curved buffer).

addLabel

public void addLabel(LabelCacheItem item,
 Rectangle2D bounds)

Adds a label into the index.

reserveArea

public void reserveArea(List<Rectangle2D> reserved)

Reserves the areas indicated by these rectangles.