Package noaa.coastwatch.render.feature

Class PolygonFeatureSource

java.lang.Object

noaa.coastwatch.render.feature.AbstractFeatureSource

noaa.coastwatch.render.feature.LineFeatureSource

noaa.coastwatch.render.feature.PolygonFeatureSource

All Implemented Interfaces:

Iterable<Feature>, FeatureSource

Direct Known Subclasses:

BinnedGSHHSReader

public abstract class PolygonFeatureSource
extends LineFeatureSource

The PolygonFeatureSource extends the LineFeatureSource class to render filled polygons as well as lines. Polygon features are maintained in a separate list, so that line features and polygon features may be rendered independently.

Since:

3.1.4

Author:

Peter Hollemans

Field Summary

Fields

Modifier and Type	Field	Description
protected List<PolygonFeature>	polygonList	The currently selected list of polygon features.

Fields inherited from class noaa.coastwatch.render.feature.AbstractFeatureSource

area, featureList

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PolygonFeatureSource()	Creates a new source with an empty list of polygons.

Method Summary

Modifier and Type	Method	Description
void	renderOutlines(Graphics2D g, EarthImageTransform trans)	Renders the selected polygon data to a graphics context as just the polygon outlines.
void	renderPolygons(Graphics2D g, EarthImageTransform trans)	Renders the selected polygon data to a graphics context.

Methods inherited from class noaa.coastwatch.render.feature.LineFeatureSource

render

Methods inherited from class noaa.coastwatch.render.feature.AbstractFeatureSource

getArea, getAttributeCount, getAttributeNameMap, getAttributes, getFilter, iterator, select, select, setAttributes, setFilter

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Details

polygonList

protected List<PolygonFeature> polygonList

The currently selected list of polygon features.

Constructor Details

PolygonFeatureSource

protected PolygonFeatureSource()

Creates a new source with an empty list of polygons.

Method Details

renderPolygons

public void renderPolygons(Graphics2D g,
 EarthImageTransform trans)

Renders the selected polygon data to a graphics context. This method differs from the LineFeatureSource.render(java.awt.Graphics2D, noaa.coastwatch.render.EarthImageTransform) method in three ways:

1. Groups of polygons are rendered as a batch using a non-zero winding rule (see the PathIterator class for details). This is done so that hierarchical levels of polygons (polygons contained within other polygons) whose winding orders are different are rendered correctly.
2. Groups of polygons that should be rendered as a batch are separated by a polygon of length zero.
3. Polygons that are detected to be discontinuous are not rendered, and all polygons in their group are also ignored. This helps to avoid strange polygon rendering results.

Parameters:

g - the graphics context for drawing.

trans - the earth image transform for converting earth locations to image points.

renderOutlines

public void renderOutlines(Graphics2D g,
 EarthImageTransform trans)

Renders the selected polygon data to a graphics context as just the polygon outlines.

Parameters:

g - the graphics context for drawing.

trans - the earth image transform for converting earth locations to image points.