Wt::Chart::WAbstractColorMap Class Reference

Maps numerical values to colors. More...

Inheritance diagram for Wt::Chart::WAbstractColorMap:

List of all members.

Public Member Functions
	WAbstractColorMap (double min, double max, WObject *parent=0)
	Constructor.
virtual WColor	toColor (double value) const =0
	Converts a numerical value to a WColor.
virtual void	createStrip (WPainter *painter, const WRectF &area=WRectF()) const =0
	Paints the colormap as a colored strip.
virtual void	paintLegend (WPainter *painter, const WRectF &area=WRectF()) const =0
	Paints the colormap as a legend.
double	minimum () const
	Returns the minimum of the colormap range.
double	maximum () const
	Returns the maximum of the colormap range.
void	setTickSpacing (int spacing)
	Sets the tickspacing for the legend as a number of line-heights.
int	tickSpacing () const
	Returns the tickspacing for the legend.
void	setFormatString (const WString &format)
	Sets the format for the labels on the colormap-legend.
const WString &	formatString () const
	Returns the format string.
void	setLabelFont (const WFont &font)
	Sets the font to be used when drawing the labels in the legend.
const WFont &	labelFont ()
	Returns the font to be used when drawing the labels in the legend.

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Detailed Description

Maps numerical values to colors.

The colormap has functionality to convert a numerical value to a WColor. For details on how, see the documentation of the implementations.

A colormap has a certain numerical range. When a colormap is painted as a colored strip or as a legend, this range is what will be presented, even if the colormap has the ability to convert values outside this range.

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Constructor & Destructor Documentation

Wt::Chart::WAbstractColorMap::WAbstractColorMap	(	double	min,
		double	max,
		WObject *	parent = 0
	)

Constructor.

Constructor taking a minimum and maximum value, determining the active range of the colormap. The default value for tickSpacing is 2 and the default label format is 2 decimal points.

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Member Function Documentation

virtual void Wt::Chart::WAbstractColorMap::createStrip	(	WPainter *	painter,
		const WRectF &	area = WRectF()
	)		const [pure virtual]

Paints the colormap as a colored strip.

This paints the colormap from the minimum to the maximum value in the provided area (default = fill the entire paintdevice). This is no legend with ticks and labels, only the colors are painted.

See also:

paintLegend()

Implemented in Wt::Chart::WStandardColorMap.

const WString& Wt::Chart::WAbstractColorMap::formatString

(

)

const

Returns the format string.

See also:

setFormatString()

const WFont& Wt::Chart::WAbstractColorMap::labelFont

(

)

Returns the font to be used when drawing the labels in the legend.

See also:

setLabelFont

virtual void Wt::Chart::WAbstractColorMap::paintLegend	(	WPainter *	painter,
		const WRectF &	area = WRectF()
	)		const [pure virtual]

Paints the colormap as a legend.

The colormap is painted as a legend with ticks and value-labels. The parameter area can be used to specify a part of the paintdevice where the legend should be drawn. When drawing the legend, the tickspacing, labelformat and labelfont are taken into account.

See also:

setTickSpacing(), setFormatString(), setLabelFont()

Implemented in Wt::Chart::WStandardColorMap.

void Wt::Chart::WAbstractColorMap::setFormatString

(

const WString &

format

)

Sets the format for the labels on the colormap-legend.

The format string is interpreted by snprintf(). The default is a float with two decimal places.

See also:

paintLegend()

void Wt::Chart::WAbstractColorMap::setLabelFont

(

const WFont &

font

)

Sets the font to be used when drawing the labels in the legend.

The default is a default constructed WFont.

See also:

paintLegend()

void Wt::Chart::WAbstractColorMap::setTickSpacing

(

int

spacing

)

Sets the tickspacing for the legend as a number of line-heights.

The tickspacing must be specified as an integer number of line-heigths. For example, the default value of 2 will leave two line-heights between the labels of the ticks.

See also:

paintLegend()

int Wt::Chart::WAbstractColorMap::tickSpacing

(

)

const

Returns the tickspacing for the legend.

See also:

setTickSpacing()