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Public Member Functions | Protected Member Functions
QgsAspectFilter Class Reference

Calculates aspect values in a window of 3x3 cells based on first order derivatives in x- and y- directions. More...

#include <qgsaspectfilter.h>

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List of all members.

Public Member Functions

 QgsAspectFilter (const QString &inputFile, const QString &outputFile, const QString &outputFormat)
 ~QgsAspectFilter ()
- Public Member Functions inherited from QgsDerivativeFilter
 QgsDerivativeFilter (const QString &inputFile, const QString &outputFile, const QString &outputFormat)
virtual ~QgsDerivativeFilter ()
- Public Member Functions inherited from QgsNineCellFilter
 QgsNineCellFilter (const QString &inputFile, const QString &outputFile, const QString &outputFormat)
 Constructor that takes input file, output file and output format (GDAL string)
virtual ~QgsNineCellFilter ()
int processRaster (QProgressDialog *p)
 Starts the calculation, reads from mInputFile and stores the result in mOutputFile.

Protected Member Functions

float processNineCellWindow (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)
 Calculates output value from nine input values.
- Protected Member Functions inherited from QgsDerivativeFilter
float calcFirstDerX (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)
 Calculates the first order derivative in x-direction according to Horn (1981)
float calcFirstDerY (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)
 Calculates the first order derivative in y-direction according to Horn (1981)

Detailed Description

Calculates aspect values in a window of 3x3 cells based on first order derivatives in x- and y- directions.

Direction is clockwise starting from north

Definition at line 24 of file qgsaspectfilter.h.


Constructor & Destructor Documentation

QgsAspectFilter::QgsAspectFilter ( const QString &  inputFile,
const QString &  outputFile,
const QString &  outputFormat 
)

Definition at line 20 of file qgsaspectfilter.cpp.

QgsAspectFilter::~QgsAspectFilter ( )

Definition at line 26 of file qgsaspectfilter.cpp.


Member Function Documentation

float QgsAspectFilter::processNineCellWindow ( float *  x11,
float *  x21,
float *  x31,
float *  x12,
float *  x22,
float *  x32,
float *  x13,
float *  x23,
float *  x33 
)
protectedvirtual

Calculates output value from nine input values.

The input values and the output value can be equal to the \ nodata value if not present or outside of the border. Must be implemented by subclasses

Implements QgsDerivativeFilter.

Definition at line 31 of file qgsaspectfilter.cpp.

References QgsDerivativeFilter::calcFirstDerX(), QgsDerivativeFilter::calcFirstDerY(), M_PI, and QgsNineCellFilter::mOutputNodataValue.


The documentation for this class was generated from the following files: