#include <Wt/WCanvasPaintDevice>
Public Member Functions | |
WCanvasPaintDevice (const WLength &width, const WLength &height, WObject *parent=0) | |
Create a canvas paint device. | |
virtual void | setChanged (WFlags< ChangeFlag > flags) |
Indicate changes in painter state. | |
virtual void | drawArc (const WRectF &rect, double startAngle, double spanAngle) |
Draw an arc. | |
virtual void | drawImage (const WRectF &rect, const std::string &imgUri, int imgWidth, int imgHeight, const WRectF &sourceRect) |
Draw an image. | |
virtual void | drawLine (double x1, double y1, double x2, double y2) |
Draw a line. | |
virtual void | drawPath (const WPainterPath &path) |
Draw a path. | |
virtual void | drawText (const WRectF &rect, WFlags< AlignmentFlag > flags, const WString &text) |
Draw text. | |
virtual void | init () |
Initialize the device for painting. | |
virtual void | done () |
Finish painting on the device. | |
virtual bool | paintActive () const |
Return whether painting is active. | |
virtual WLength | width () const |
Returns the device width. | |
virtual WLength | height () const |
Returns the device height. | |
Protected Member Functions | |
virtual WPainter * | painter () const |
Return the painter that is currently painting on the device. | |
virtual void | setPainter (WPainter *painter) |
Set the painter. |
The WCanvasPaintDevice is used by WPaintedWidget to render to the browser using the HTML 5 <canvas> element. You usually will not use the device directly, but rather rely on WPaintedWidget to use this device when appropriate.
void Wt::WCanvasPaintDevice::setChanged | ( | WFlags< ChangeFlag > | flags | ) | [virtual] |
Indicate changes in painter state.
The flags argument is the logical OR of one or more change flags.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::drawArc | ( | const WRectF & | rect, | |
double | startAngle, | |||
double | spanAngle | |||
) | [virtual] |
Draw an arc.
The arc is defined as in WPainter::drawArc(const WRectF&, startAngle, spanAngle), but the angle is expressed in degrees.
The arc must be stroked, filled, and transformed using the current painter settings.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::drawImage | ( | const WRectF & | rect, | |
const std::string & | imageUri, | |||
int | imgWidth, | |||
int | imgHeight, | |||
const WRectF & | sourceRect | |||
) | [virtual] |
Draw 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::WCanvasPaintDevice::drawLine | ( | double | x1, | |
double | y1, | |||
double | x2, | |||
double | y2 | |||
) | [virtual] |
Draw a line.
The line must be stroked and transformed using the current painter settings.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::drawPath | ( | const WPainterPath & | path | ) | [virtual] |
Draw a path.
The path must be stroked, filled, and transformed using the current painter settings.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::drawText | ( | const WRectF & | rect, | |
WFlags< AlignmentFlag > | flags, | |||
const WString & | text | |||
) | [virtual] |
Draw text.
The text must be rendered, stroked and transformed using the current painter settings.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::init | ( | ) | [virtual] |
Initialize the device for painting.
This method is called when a WPainter starts painting.
Implements Wt::WPaintDevice.
void Wt::WCanvasPaintDevice::done | ( | ) | [virtual] |
Finish painting on the device.
This method is called when a WPainter stopped painting.
Implements Wt::WPaintDevice.
virtual bool Wt::WCanvasPaintDevice::paintActive | ( | ) | const [inline, virtual] |
virtual WLength Wt::WCanvasPaintDevice::width | ( | ) | const [inline, virtual] |
Returns the device width.
The device width, in pixels, establishes the width of the device coordinate system.
Implements Wt::WPaintDevice.
virtual WLength Wt::WCanvasPaintDevice::height | ( | ) | const [inline, virtual] |
Returns the device height.
The device height, in pixels, establishes the height of the device coordinate system.
Implements Wt::WPaintDevice.
virtual WPainter* Wt::WCanvasPaintDevice::painter | ( | ) | const [inline, protected, virtual] |
Return the painter that is currently painting on the device.
Implements Wt::WPaintDevice.