A pixel density represents the number of pixel in raster data over a unit of area in a given coordinate reference. More...

#include <luciad/rasters/PixelDensity.h>

Public Member Functions
	PixelDensity (std::shared_ptr< CoordinateReference > reference, double value)
	Construct a PixelDensity object. More...

const std::shared_ptr< CoordinateReference > &	getReference () const

double	getValue () const

Static Public Member Functions
static PixelDensity	fromSampleDistance (double distanceInMeters, Coordinate sampleLocation, std::shared_ptr< CoordinateReference > pixelDensityReference)
	Creates a pixel density from a sample distance. More...

Detailed Description

A pixel density represents the number of pixel in raster data over a unit of area in a given coordinate reference.

Concretely it's a value with the following units: px² / uom². Here, 'uom' mean the unit of measure of the coordinate reference in which the pixel density is expressed. It is typically meters.

More information on this, and hints on its usages can be fount in the related article: Retrieving height data.

A typical way to create a pixel density is by converting it from a sample distance. Imagine for example that you want to sample elevation data along a line, and get an elevation value every meter. In that case, you can use the fromSampleDistance method to create a pixel density where the distance between every pixel corresponds to 1 meter.

Since: 2023.0

Constructor & Destructor Documentation

◆ PixelDensity()

luciad::PixelDensity::PixelDensity	(	std::shared_ptr< CoordinateReference >	reference,
		double	value
	)

Construct a PixelDensity object.

Parameters

reference	the coordinate reference, cannot be `nullptr`
value	the density value expressed in the given coordinate reference, must be greater than 0

Member Function Documentation

◆ fromSampleDistance()

static PixelDensity luciad::PixelDensity::fromSampleDistance	(	double	distanceInMeters,
		Coordinate	sampleLocation,
		std::shared_ptr< CoordinateReference >	pixelDensityReference
	)

static

Creates a pixel density from a sample distance.

The resulting PixelDensity, expressed in the given coordinate reference, is such that the distance between pixels corresponds roughly with the provided distance in meters at the given location.

Parameters

distanceInMeters	the desired distance between two adjacent samples, in meters
sampleLocation	the point at which the distance between samples must be equal to distanceInMeters
pixelDensityReference	the reference in which sampleLocation, and the resulting PixelDensity, is expressed

Returns: a pixel density that meets the requirements

Exceptions

luciad::InvalidArgumentException if pixelDensityReference is neither a grid nor a geodetic reference.

◆ getReference()

const std::shared_ptr< CoordinateReference > & luciad::PixelDensity::getReference ( ) const

Returns: the pixel density coordinate reference

◆ getValue()

double luciad::PixelDensity::getValue ( ) const

Returns: the pixel density value

Public Member Functions