qwtmatrixrasterdata(3) [debian man page]

QwtMatrixRasterData(3)						 Qwt User's Guide					    QwtMatrixRasterData(3)

NAME

       QwtMatrixRasterData -

       A class representing a matrix of values as raster data.

SYNOPSIS

       #include <qwt_matrix_raster_data.h>

       Inherits QwtRasterData.

   Public Types
       enum ResampleMode { NearestNeighbour, BilinearInterpolation }

   Public Member Functions
       QwtMatrixRasterData ()
       virtual ~QwtMatrixRasterData ()
       void setResampleMode (ResampleMode mode)
       ResampleMode resampleMode () const
       virtual void setInterval (Qt::Axis, const QwtInterval &)
       void setValueMatrix (const QVector< double > &values, size_t numColumns)
       const QVector< double > valueMatrix () const
       size_t numColumns () const
       size_t numRows () const
       virtual QRectF pixelHint (const QRectF &) const
       virtual double value (double x, double y) const

Detailed Description
       A class representing a matrix of values as raster data.

       QwtMatrixRasterData implements an interface for a matrix of equidistant values, that can be used by a QwtPlotRasterItem. It implements a
       couple of resampling algorithms, to provide values for positions, that or not on the value matrix.

Member Enumeration Documentation
   enum QwtMatrixRasterData::ResampleMode
       Resampling algorithm The default setting is NearestNeighbour;.

       Enumerator:

       NearestNeighbour
	      Return the value from the matrix, that is nearest to the the requested position.

       BilinearInterpolation
	      Interpolate the value from the distances and values of the 4 surrounding values in the matrix,

Constructor &; Destructor Documentation
   QwtMatrixRasterData::QwtMatrixRasterData ()
       Constructor.

   QwtMatrixRasterData::~QwtMatrixRasterData () [virtual]
       Destructor.

Member Function Documentation
   size_t QwtMatrixRasterData::numColumns () const Returns:
	   Number of columns of the value matrix

       See also:
	   valueMatrix(), numRows(), setValueMatrix()

   size_t QwtMatrixRasterData::numRows () const Returns:
	   Number of rows of the value matrix

       See also:
	   valueMatrix(), numColumns(), setValueMatrix()

   QRectF QwtMatrixRasterData::pixelHint (const QRectF &) const [virtual]
       Pixel hint. .IP "o" 2 NearestNeighbour
	pixelHint() returns the surrounding pixel of the top left value in the matrix.

       o BilinearInterpolation
	  Returns an empty rectangle recommending to render in target device ( f.e. screen ) resolution.

       See also:
	   ResampleMode, setMatrix(), setInterval()

       Reimplemented from QwtRasterData.

   QwtMatrixRasterData::ResampleMode QwtMatrixRasterData::resampleMode () const Returns:
	   resampling algorithm

       See also:
	   setResampleMode(), value()

   void QwtMatrixRasterData::setInterval (Qt::Axisaxis, const QwtInterval &interval) [virtual]
       Assign the bounding interval for an axis. Setting the bounding intervals for the X/Y axis is mandatory to define the positions for the
       values of the value matrix. The interval in Z direction defines the possible range for the values in the matrix, what is f.e used by
       QwtPlotSpectrogram to map values to colors. The Z-interval might be the bounding interval of the values in the matrix, but usually it
       isn't. ( f.e a interval of 0.0-100.0 for values in percentage )

       Parameters:
	   axis X, Y or Z axis
	   interval Interval

       See also:
	   QwtRasterData::interval(), setValueMatrix()

       Reimplemented from QwtRasterData.

   void QwtMatrixRasterData::setResampleMode (ResampleModemode)
       Set the resampling algorithm. Parameters:
	   mode Resampling mode

       See also:
	   resampleMode(), value()

   void QwtMatrixRasterData::setValueMatrix (const QVector< double > &values, size_tnumColumns)
       Assign a value matrix. The positions of the values are calculated by dividing the bounding rectangle of the X/Y intervals into equidistant
       rectangles ( pixels ). Each value corresponds to the center of a pixel.

       Parameters:
	   values Vector of values
	   numColumns Number of columns

       See also:
	   valueMatrix(), numColumns(), numRows(), setInterval()()

   double QwtMatrixRasterData::value (doublex, doubley) const [virtual] Returns:
	   the value at a raster position

       Parameters:
	   x X value in plot coordinates
	   y Y value in plot coordinates

       See also:
	   ResampleMode

       Implements QwtRasterData.

   const QVector< double > QwtMatrixRasterData::valueMatrix () const Returns:
	   Value matrix

       See also:
	   setValueMatrix(), numColumns(), numRows(), setInterval()

Author
       Generated automatically by Doxygen for Qwt User's Guide from the source code.

Version 6.0.0							  Fri Apr 15 2011					    QwtMatrixRasterData(3)