A class that encapsulates grid data and provides interpolation methods. More...

#include <qwt_grid_raster_data.h>

Inheritance diagram for QwtGridRasterData:

Classes
class	PrivateData

Public Types
enum	ResampleMode { NearestNeighbour , BilinearInterpolation , BicubicInterpolation }
	Resampling algorithm The default setting is NearestNeighbour;. More...

Public Types inherited from QwtRasterData
enum	Attribute { WithoutGaps = 0x01 }
	Raster data attributes. More...

enum	ConrecFlag { IgnoreAllVerticesOnLevel = 0x01 , IgnoreOutOfRange = 0x02 }
	Flags to modify the contour algorithm. More...

typedef QMap< double, QPolygonF >	ContourLines
	Contour lines.

Public Member Functions
void	setResampleMode (ResampleMode mode)
	Set the resample method.

ResampleMode	resampleMode () const
	Get the current resample method.

virtual QwtInterval	interval (Qt::Axis axis) const QWT_OVERRIDE QWT_FINAL

void	setValue (const QVector< double > &x, const QVector< double > &y, const QVector< QVector< double > > &v)
	Set new x-axis, y-axis, and data matrix.

virtual double	value (double x, double y) const QWT_OVERRIDE

virtual QRectF	pixelHint (const QRectF &) const QWT_OVERRIDE
	Pixel hint.

int	xSize () const
	x 值对应的内容

int	ySize () const
	y值对应的内容

std::pair< int, int >	valueSize () const
	y值对应的内容

double	atValue (int xIndex, int yIndex) const
	value值对应的内容

double	atX (int xIndex) const
	Get the x-axis values.

double	atY (int yIndex) const
	Get the y-axis values.

Public Member Functions inherited from QwtRasterData
	QwtRasterData ()
	Constructor.

virtual	~QwtRasterData ()
	Destructor.

void	setAttribute (Attribute, bool on=true)
	Specify an attribute of the data.

bool	testAttribute (Attribute) const

virtual void	initRaster (const QRectF &, const QSize &raster)
	Initialize a raster.

virtual void	discardRaster ()
	Discard a raster.

virtual ContourLines	contourLines (const QRectF &rect, const QSize &raster, const QList< double > &levels, ConrecFlags) const
	Calculate contour lines.

Detailed Description

A class that encapsulates grid data and provides interpolation methods.

This class inherits from QwtRasterData and is used to represent 2D grid data. It supports various interpolation methods such as nearest neighbor and bilinear interpolation.

此类继承自 QwtRasterData，用于表示二维网格数据。它支持多种插值方法，例如最近邻插值和双线性插值。

Member Enumeration Documentation

◆ ResampleMode

enum QwtGridRasterData::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,.
BicubicInterpolation	Interpolate the value from the 16 surrounding values in the matrix using hermite bicubic interpolation.

Member Function Documentation

◆ atValue()

double QwtGridRasterData::atValue	(	int	xIndex,
		int	yIndex
	)		const

value值对应的内容

Parameters

ix

Returns

◆ atX()

double QwtGridRasterData::atX ( int xIndex ) const

Get the x-axis values.

获取 x 轴值。

Returns: The x-axis values. / x 轴值。

◆ atY()

double QwtGridRasterData::atY ( int yIndex ) const

Get the y-axis values.

获取 y 轴值。

Returns: The y-axis values. / y 轴值。

◆ interval()

QwtInterval QwtGridRasterData::interval ( Qt::Axis ) const

virtual

Returns: Bounding interval for an axis

See also: setInterval

Implements QwtRasterData.

◆ pixelHint()

QRectF QwtGridRasterData::pixelHint ( const QRectF & area ) const

virtual

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.

Width and height of the hint need to be the horizontal and vertical distances between 2 neighbored points. The center of the hint has to be the position of any point ( it doesn't matter which one ).

An empty hint indicates, that there are values for any detail level.

Limiting the resolution of the image might significantly improve the performance and heavily reduce the amount of memory when rendering a QImage from the raster data.

The default implementation returns an empty rectangle recommending to render in target device ( f.e. screen ) resolution.

Parameters

area	In most implementations the resolution of the data doesn't depend on the requested area.

Returns: Bounding rectangle of a pixel

Reimplemented from QwtRasterData.

◆ resampleMode()

QwtGridRasterData::ResampleMode QwtGridRasterData::resampleMode ( ) const

Get the current resample method.

Returns the currently active resample method.

返回当前激活的插值方法。

Returns: The current resample method. 当前插值方法。

See also: setResampleMode(), value()

◆ setResampleMode()

void QwtGridRasterData::setResampleMode ( QwtGridRasterData::ResampleMode mode )

Set the resample method.

Sets the resample method to be used when querying values.

设置查询值时使用的插值方法。

Parameters

method The resample method to use. 要使用的插值方法。

See also: resampleMode(), value()

◆ setValue()

void QwtGridRasterData::setValue	(	const QVector< double > &	x,
		const QVector< double > &	y,
		const QVector< QVector< double > > &	v
	)

Set new x-axis, y-axis, and data matrix.

data matrix is look like that:

|column[0]|column[1]| ... |column[m]| +------—+------—+--—+------—+ | [x0,yn] | [x1,yn] | ... | [xm,yn] | → yAxis[n] 对应行 +------—+------—+--—+------—+ | ... | ... | ... | ... | +------—+------—+--—+------—+ | [x0,y1] | [x1,y1] | ... | [xm,y1] | → yAxis[1] 对应行 +------—+------—+--—+------—+ | [x0,y0] | [x1,y0] | ... | [xm,y0] | → yAxis[0] 对应行 +------—+------—+--—+------—+ ↑ ↑ ↑ ↑ xAxis[0] xAxis[1] ... xAxis[m]

so (data matrix).size = xAxis.size,(data matrix).at(n).size = yAxis.szie

设置新的 x 轴、y 轴和数据矩阵。数据矩阵是一个vector<vector> ,数据矩阵.size = xAxis.size,数据矩阵.at(n).size = yAxis.size

Parameters

xAxis	The x-axis values. / x 轴值。
yAxis	The y-axis values. / y 轴值。
data	The 2D data matrix. / 二维数据矩阵。

◆ value()

double QwtGridRasterData::value	(	double	x,
		double	y
	)		const

virtual

Returns: the value at a raster position

Parameters

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

Implements QwtRasterData.

◆ valueSize()

std::pair< int, int > QwtGridRasterData::valueSize ( ) const

y值对应的内容

Parameters

ix

Returns

◆ xSize()

int QwtGridRasterData::xSize ( ) const

x 值对应的内容

Parameters

ix

Returns

◆ ySize()

int QwtGridRasterData::ySize ( ) const

y值对应的内容

Parameters

ix

Returns

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

/home/runner/work/QWT/QWT/src/qwt_grid_raster_data.h
/home/runner/work/QWT/QWT/src/qwt_grid_raster_data.cpp

Classes

Public Types

Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ ResampleMode

Member Function Documentation

◆ atValue()

◆ atX()

◆ atY()

◆ interval()

◆ pixelHint()

◆ resampleMode()

◆ setResampleMode()

◆ setValue()

◆ value()

◆ valueSize()

◆ xSize()

◆ ySize()