Wt  4.0.2
Public Member Functions | Protected Member Functions | List of all members
Wt::WMeasurePaintDevice Class Reference

WMeasurePaintDevice Wt/WMeasurePaintDevice Wt/WMeasurePaintDevice. More...

#include <WMeasurePaintDevice.h>

Inheritance diagram for Wt::WMeasurePaintDevice:
Inheritance graph
[legend]

Public Member Functions

 WMeasurePaintDevice (WPaintDevice *paintDevice)
 Creates a paint device to measure for the underlying device.
 
WRectF boundingRect () const
 Returns the bounding rectangle of everything painted so far. More...
 
virtual WFlags< PaintDeviceFeatureFlagfeatures () const override
 Returns device features.
 
virtual void setChanged (WFlags< PainterChangeFlag > flags) override
 Indicates changes in painter state. More...
 
virtual void drawArc (const WRectF &rect, double startAngle, double spanAngle) override
 Draws an arc. More...
 
virtual void drawImage (const WRectF &rect, const std::string &imgUri, int imgWidth, int imgHeight, const WRectF &sourceRect) override
 Draws an image. More...
 
virtual void drawLine (double x1, double y1, double x2, double y2) override
 Draws a line. More...
 
virtual void drawRect (const WRectF &rectangle) override
 Draws a rectangle. More...
 
virtual void drawPath (const WPainterPath &path) override
 Draws a path. More...
 
virtual void drawText (const WRectF &rect, WFlags< AlignmentFlag > alignmentFlags, TextFlag textFlag, const WString &text, const WPointF *clipPoint) override
 Draws text. More...
 
virtual WTextItem measureText (const WString &text, double maxWidth=-1, bool wordWrap=false) override
 Measures rendered text size. More...
 
virtual WFontMetrics fontMetrics () override
 Returns font metrics. More...
 
virtual void init () override
 Initializes the device for painting. More...
 
virtual void done () override
 Finishes painting on the device. More...
 
virtual bool paintActive () const override
 Returns whether painting is active. More...
 
virtual WLength width () const override
 Returns the device width. More...
 
virtual WLength height () const override
 Returns the device height. More...
 
- Public Member Functions inherited from Wt::WPaintDevice
virtual ~WPaintDevice ()
 Destructor. More...
 

Protected Member Functions

virtual WPainterpainter () const override
 Returns the painter that is currently painting on the device. More...
 
virtual void setPainter (WPainter *painter) override
 Sets the painter.
 

Additional Inherited Members

- Public Types inherited from Wt::WPaintDevice
typedef PaintDeviceFeatureFlag FeatureFlag
 Typedef for enum Wt::PaintDeviceFeatureFlag.
 

Detailed Description

WMeasurePaintDevice Wt/WMeasurePaintDevice Wt/WMeasurePaintDevice.

This implements a (pseudo)-paintdevice which measures the bounding rect of whatever is being painted on it, using fontmetrics from the underlying device.

The only output of the device is the computation of a bounding rect which is returned by boundingRect().

Member Function Documentation

WRectF Wt::WMeasurePaintDevice::boundingRect ( ) const

Returns the bounding rectangle of everything painted so far.

The bounding rect is returned in device coordinates (i.e. after all transformations applied).

void Wt::WMeasurePaintDevice::done ( )
overridevirtual

Finishes painting on the device.

This method is called when a WPainter stopped painting.

See also
WPainter::end()

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawArc ( const WRectF rect,
double  startAngle,
double  spanAngle 
)
overridevirtual

Draws an arc.

The arc describes the segment of an ellipse enclosed by the rect. The segment starts at startAngle, and spans an angle given by spanAngle. These angles have as unit degree, and are measured counter-clockwise starting from the 3 o'clock position.

The arc must be stroked, filled, and transformed using the current painter settings.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawImage ( const WRectF rect,
const std::string &  imageUri,
int  imgWidth,
int  imgHeight,
const WRectF sourceRect 
)
overridevirtual

Draws an image.

Draws sourceRect from the image with URL imageUri and original dimensions imgWidth and imgHeight to the location, into the rectangle defined by rect.

The image is transformed using the current painter settings.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawLine ( double  x1,
double  y1,
double  x2,
double  y2 
)
overridevirtual

Draws a line.

The line must be stroked and transformed using the current painter settings.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawPath ( const WPainterPath path)
overridevirtual

Draws a path.

The path must be stroked, filled, and transformed using the current painter settings.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawRect ( const WRectF rectangle)
overridevirtual

Draws a rectangle.

The rect must be stroked, filled, and transformed using the current painter settings.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::drawText ( const WRectF rect,
WFlags< AlignmentFlag alignmentFlags,
TextFlag  textFlag,
const WString text,
const WPointF clipPoint 
)
overridevirtual

Draws text.

The text must be rendered, stroked and transformed using the current painter settings.

If clipPoint is not null, a check is performed whether the point is inside of the current clip area. If not, the text is not drawn.

Implements Wt::WPaintDevice.

WFontMetrics Wt::WMeasurePaintDevice::fontMetrics ( )
overridevirtual

Returns font metrics.

This returns font metrics for the current font.

Throws a std::logic_error if the underlying device does not provide font metrics.

Implements Wt::WPaintDevice.

WLength Wt::WMeasurePaintDevice::height ( ) const
overridevirtual

Returns the device height.

The device height, in pixels, establishes the height of the device coordinate system.

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::init ( )
overridevirtual

Initializes the device for painting.

This method is called when a WPainter starts painting.

See also
WPainter::begin(WPaintDevice *), painter()

Implements Wt::WPaintDevice.

WTextItem Wt::WMeasurePaintDevice::measureText ( const WString text,
double  maxWidth = -1,
bool  wordWrap = false 
)
overridevirtual

Measures rendered text size.

Returns the bounding rect of the given text when rendered using the current font.

If maxWidth != -1, then the text is truncated to fit in the width.

If wordWrap = true then text is truncated only at word boundaries. Note that in this case the whitespace at the truncated position is included in the text but not accounted for by the returned width (since usually you will not render the whitespace at the end of a line).

Throws a std::logic_error if the underlying device does not provide font metrics.

Implements Wt::WPaintDevice.

virtual bool Wt::WMeasurePaintDevice::paintActive ( ) const
overridevirtual

Returns whether painting is active.

See also
init(), painter()

Implements Wt::WPaintDevice.

virtual WPainter* Wt::WMeasurePaintDevice::painter ( ) const
overrideprotectedvirtual

Returns the painter that is currently painting on the device.

See also
init()

Implements Wt::WPaintDevice.

void Wt::WMeasurePaintDevice::setChanged ( WFlags< PainterChangeFlag flags)
overridevirtual

Indicates changes in painter state.

The flags argument is the logical OR of one or more change flags.

See also
ChangeFlag

Implements Wt::WPaintDevice.

WLength Wt::WMeasurePaintDevice::width ( ) const
overridevirtual

Returns the device width.

The device width, in pixels, establishes the width of the device coordinate system.

Implements Wt::WPaintDevice.


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