Package uk.ac.rdg.resc.edal.graphics.utils

Class GraphicsUtils

java.lang.Object

uk.ac.rdg.resc.edal.graphics.utils.GraphicsUtils

All Implemented Interfaces:

Serializable

public class GraphicsUtils
extends Object
implements Serializable

Class containing static utility methods for dealing with graphics

Author:

Guy Griffiths

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	GraphicsUtils.ColorAdapter

Constructor Summary

Constructors

Constructor	Description
GraphicsUtils()

Method Summary

Modifier and Type	Method	Description
static String	colourToHtmlString(Color colour)	Converts a Color to an HTML String (#RRGGBB), ignoring transparency.
static String	colourToString(Color colour)	Converts a Color to an HTML-like String (#AARRGGBB), with additional cases for transparent / null values
static BufferedImage	drawCategoricalLegend(Map<Integer,Parameter.Category> categories)	Renders a legend for categorical data
static Extent<Float>	estimateValueRange(Dataset dataset, String varId)	Estimate the range of values in this layer by reading a sample of data from the default time and elevation.
static Collection<? extends DiscreteFeature<?,?>>	extractGeneralMapFeatures(Dataset dataset, String varId, PlottingDomainParams params)	Convenience method to extract map features for a single variable in a generic dataset.
static Color[]	generateColourSet(Color[] palette, int numColorBands)	Gets a version of this palette with the given number of color bands, either by subsampling or interpolating the existing palette
static Map<Integer,Color>	getColourMapForCategories(Map<Integer,Parameter.Category> categories)
static Collection<String>	getNamedColours()
static Color	parseColour(String colourString)	Parses a string to obtain a Color.
static BufferedImage	plotDefaultImage(Dataset dataset, String varId, int width, int height)	Draws a raster image from the supplied dataset and variable
static double	roundToSignificantFigures(double num, int n)	Rounds a double to a number of significant figures Taken from: http://stackoverflow.com/questions/202302/rounding-to-an-arbitrary -number-of-significant-digits

Methods inherited from class java.lang.Object

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

Constructor Detail

GraphicsUtils

public GraphicsUtils()

Method Detail

extractGeneralMapFeatures

public static Collection<? extends DiscreteFeature<?,?>> extractGeneralMapFeatures(Dataset dataset,
                                                                                         String varId,
                                                                                         PlottingDomainParams params)

Convenience method to extract map features for a single variable in a generic dataset.

Parameters:

dataset - The Dataset to extract features from

varId - The variable ID to extract

params - The PlottingDomainParams representing the domain to extract onto

Returns:

A Collection of DiscreteFeatures

parseColour

public static Color parseColour(String colourString)
                         throws EdalParseException

Parses a string to obtain a Color.

Parameters:

colourString - A string of one of the forms:

0xRRGGBB

0xAARRGGBB

#RRGGBB

#AARRGGBB

"transparent"

"extend"

A named colour. See getNamedColours() for a full list

Returns:

A Color representing the string, or null if "extend" was supplied

Throws:

EdalParseException - If the format of the string does not fall into one of the above categories

getNamedColours

public static Collection<String> getNamedColours()

Returns:

The available named colours

colourToString

public static String colourToString(Color colour)

Converts a Color to an HTML-like String (#AARRGGBB), with additional cases for transparent / null values

Parameters:

colour - The colour to represent as a String

Returns:

The HTML representation of the Color, or null if a null Color was supplied.

colourToHtmlString

public static String colourToHtmlString(Color colour)

Converts a Color to an HTML String (#RRGGBB), ignoring transparency.

Parameters:

colour - The colour to represent as a String

Returns:

The HTML representation of the Color, or null if a null Color was supplied.

estimateValueRange

public static Extent<Float> estimateValueRange(Dataset dataset,
                                               String varId)

Estimate the range of values in this layer by reading a sample of data from the default time and elevation. If the given variable is not found, a default range of 0-100 is returned

Parameters:

dataset - The dataset containing the variable to estimate

varId - The ID of the variable to estimate

Returns:

An approximate value range

roundToSignificantFigures

public static double roundToSignificantFigures(double num,
                                               int n)

Rounds a double to a number of significant figures Taken from: http://stackoverflow.com/questions/202302/rounding-to-an-arbitrary -number-of-significant-digits

Parameters:

num - The number to round

n - The number of significant figures

Returns:

The rounded number

generateColourSet

public static Color[] generateColourSet(Color[] palette,
                                        int numColorBands)

Gets a version of this palette with the given number of color bands, either by subsampling or interpolating the existing palette

Parameters:

numColorBands - The number of bands of colour to be used in the new palette

Returns:

An array of Colors, with length numColorBands

getColourMapForCategories

public static Map<Integer,Color> getColourMapForCategories(Map<Integer,Parameter.Category> categories)

drawCategoricalLegend

public static BufferedImage drawCategoricalLegend(Map<Integer,Parameter.Category> categories)

Renders a legend for categorical data

Parameters:

categories - The categories to draw a legend for

Returns:

The resulting BufferedImage

plotDefaultImage

public static BufferedImage plotDefaultImage(Dataset dataset,
                                             String varId,
                                             int width,
                                             int height)

Draws a raster image from the supplied dataset and variable

Parameters:

dataset - The dataset containing the data

varId - The ID of the variable to plot

width - The desired width of the output image

height - The desired height of the output image

Returns:

A BufferedImage containing the plot