LuciadCPillar 2024.0.04

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 
Returns the pixel density coordinate reference. More...  
double  getValue () const 
Returns the pixel density value. More...  
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...  
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.
luciad::PixelDensity::PixelDensity  (  std::shared_ptr< CoordinateReference >  reference, 
double  value  
) 
Construct a PixelDensity object.
reference  the coordinate reference, cannot be nullptr 
value  the density value expressed in the given coordinate reference, must be greater than 0 

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.
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 
luciad::InvalidArgumentException  if pixelDensityReference is neither a grid nor a geodetic reference. 
const std::shared_ptr< CoordinateReference > & luciad::PixelDensity::getReference  (  )  const 
Returns the pixel density coordinate reference.
double luciad::PixelDensity::getValue  (  )  const 
Returns the pixel density value.