| Qwt User's Guide
    6.1.3
    | 
A class representing a matrix of values as raster data. More...
#include <qwt_matrix_raster_data.h>

| Public Types | |
| enum | ResampleMode { NearestNeighbour, BilinearInterpolation } | 
| Resampling algorithm The default setting is NearestNeighbour;.  More... | |
|  Public Types inherited from QwtRasterData | |
| enum | ConrecFlag { IgnoreAllVerticesOnLevel = 0x01, IgnoreOutOfRange = 0x02 } | 
| Flags to modify the contour algorithm.  More... | |
| typedef QMap< double, QPolygonF > | ContourLines | 
| Contour lines. | |
| typedef QFlags< ConrecFlag > | ConrecFlags | 
| Flags to modify the contour algorithm. | |
| Public Member Functions | |
| QwtMatrixRasterData () | |
| Constructor. | |
| virtual | ~QwtMatrixRasterData () | 
| Destructor. | |
| void | setResampleMode (ResampleMode mode) | 
| Set the resampling algorithm.  More... | |
| ResampleMode | resampleMode () const | 
| virtual void | setInterval (Qt::Axis, const QwtInterval &) | 
| Assign the bounding interval for an axis.  More... | |
| void | setValueMatrix (const QVector< double > &values, int numColumns) | 
| Assign a value matrix.  More... | |
| const QVector< double > | valueMatrix () const | 
| void | setValue (int row, int col, double value) | 
| Change a single value in the matrix.  More... | |
| int | numColumns () const | 
| int | numRows () const | 
| virtual QRectF | pixelHint (const QRectF &) const | 
| Calculate the pixel hint.  More... | |
| virtual double | value (double x, double y) const | 
|  Public Member Functions inherited from QwtRasterData | |
| QwtRasterData () | |
| Constructor. | |
| virtual | ~QwtRasterData () | 
| Destructor. | |
| const QwtInterval & | interval (Qt::Axis) const | 
| virtual void | initRaster (const QRectF &, const QSize &raster) | 
| Initialize a raster.  More... | |
| virtual void | discardRaster () | 
| Discard a raster.  More... | |
| virtual ContourLines | contourLines (const QRectF &rect, const QSize &raster, const QList< double > &levels, ConrecFlags) const | 
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.
| int QwtMatrixRasterData::numColumns | ( | ) | const | 
| int QwtMatrixRasterData::numRows | ( | ) | const | 
| 
 | virtual | 
Calculate the pixel hint.
pixelHint() returns the geometry of a pixel, that can be used to calculate the resolution and alignment of the plot item, that is representing the data.
| area | Requested area, ignored | 
Reimplemented from QwtRasterData.
| QwtMatrixRasterData::ResampleMode QwtMatrixRasterData::resampleMode | ( | ) | const | 
| 
 | 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 )
| axis | X, Y or Z axis | 
| interval | Interval | 
Reimplemented from QwtRasterData.
| void QwtMatrixRasterData::setResampleMode | ( | ResampleMode | mode | ) | 
| void QwtMatrixRasterData::setValue | ( | int | row, | 
| int | col, | ||
| double | value | ||
| ) | 
Change a single value in the matrix.
| row | Row index | 
| col | Column index | 
| value | New value | 
| void QwtMatrixRasterData::setValueMatrix | ( | const QVector< double > & | values, | 
| int | numColumns | ||
| ) | 
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.
| values | Vector of values | 
| numColumns | Number of columns | 
| 
 | virtual | 
| x | X value in plot coordinates | 
| y | Y value in plot coordinates | 
Implements QwtRasterData.
| const QVector< double > QwtMatrixRasterData::valueMatrix | ( | ) | const |