LCDBuilder: LCDPaintEngine Class Reference

bool LCDPaintEngine::begin ( QPaintDevice * device )

Set the controller for the paint engine the controller must be valid loaded and initialized.

Exceptions:

AccessFailureException

is thrown when the device is not a LCDPaintDevice

Parameters:

device

must be a LCDPaintDevice when we wan't to draw on a LCD and we wan't so it's required ;)

Returns:: true on success, otherwise false

void LCDPaintEngine::drawEllipse ( const QRect & rect )

It use the very fast Bresenham Ellipse Algorithm to draw an ellipse on a device. This algorithm don't use the CPU intensive sin or cos functions it calculates only with full integer values so this is very fast.

Parameters:

rect

is the bounding rectangle of the ellipse, it adjusts exact into this rectangle

void LCDPaintEngine::drawEllipse ( const QRectF & rect )

This is an overloaded member function, provided for convenience.

See also:: drawEllipse(const QRect&)

Parameters:

rect

is converted into QRect

void LCDPaintEngine::drawImage	(	const QRectF &	r,
		const QImage &	image,
		const QRectF &	sr,
		Qt::ImageConversionFlags	flags = `Qt::AutoColor`
	)

Draw the part of the image specified by the sr rectangle in the given rectangle. Then the method convert the QImage into a QPixmap with the given conversion flags after that it will call the drawPixmap() method to draw it finally on a device.

Parameters:

	r	rectangle
	image	is converted into QPixmap
	sr	source rectangle
	flags	conversion flags

See also:: drawPixmap()

void LCDPaintEngine::drawLines	(	const QLine *	lines,
		int	lineCount
	)

It use the very fast Bresenham Algorithm to draw the lines on a device. The algorithm uses only integer addition and subtraction all of which are very cheap operations in standard computer architectures.

Parameters:

	lines	is an array of lines
	lineCount	count of lines in the array

void LCDPaintEngine::drawLines	(	const QLineF *	lines,
		int	lineCount
	)

This is an overloaded member function, provided for convenience.

Parameters:

	lines	is converted into QLine
	lineCount	count of lines in the array

See also:: drawLines(const QLine*, int)

void LCDPaintEngine::drawPath ( const QPainterPath & path )

fallback mechanism for other drawing methods useful to draw objects that has filled brushes or thicker pens.

Parameters:

path

will be drawn on a device

void LCDPaintEngine::drawPixmap	(	const QRectF &	r,
		const QPixmap &	pixmap,
		const QRectF &	_sr
	)

Draw the part of the pixmap specified by the sr rectangle in the given r on a device. If the pixmap has an alpha channel then it will extracts the alpha channel from this image as an 8 bit gray scale image. You can draw colored or greyscaled images but then every rgb pixel will be converted into a grey value pixel. The value of the pixel determines if a pixel will be set (value >= 125) or not (value < 125). To increase the quality of the image you can dither it before you call this method. For a good quality you can use the Floyd Steinberg dithering algorithm.

Note:: Dithering will be automaticly done when you are using the GraphicPixmap class.

Parameters:

	r	rectangle gives the position and the size of the pixmap
	pixmap	will be drawn on a device
	_sr	source rectangle

void LCDPaintEngine::drawPoints	(	const QPoint *	points,
		int	pointCount
	)

Draws all points in the array on a device.

Parameters:

	points	is an array of points
	pointCount	count of points in the array

void LCDPaintEngine::drawPoints	(	const QPointF *	points,
		int	pointCount
	)

This is an overloaded member function, provided for convenience.

Parameters:

	points	is converted into QPoint*
	pointCount	count of points in the array

See also:: drawPoint(const QPoint*, int)

void LCDPaintEngine::drawPolygon	(	const QPoint *	points,
		int	pointCount,
		QPaintEngine::PolygonDrawMode	mode
	)

Draws a polygon on a device. The points describes a polygon; every point is with a line connected to the next point; the last point is connected with the start point.

Parameters:

	points	is an array of points
	pointCount	count of points in the array
	mode	is not used

void LCDPaintEngine::drawPolygon	(	const QPointF *	points,
		int	polyCount,
		QPaintEngine::PolygonDrawMode	mode
	)

This is an overloaded member function, provided for convenience.

Parameters:

	points	is converted into QPoint*
	polyCount	count of points in the array
	mode	is not used

See also:: drawPolygon(const QPoint*, int, QPaintEngine::PolygonDrawMode)

void LCDPaintEngine::drawRects	(	const QRect *	rects,
		int	rectCount
	)

Draws a rectangle on a device.

Parameters:

	rects	is an array of rectangles
	rectCount	count of rectangles in the array

void LCDPaintEngine::drawRects	(	const QRectF *	rects,
		int	rectCount
	)

This is an overloaded member function, provided for convenience.

Parameters:

	rects	is converted into QRectangle*
	rectCount	count of rectangles in the array

See also:: drawRects(const QRect*, int)

void LCDPaintEngine::drawTextItem	(	const QPointF &	p,
		const QTextItem &	textItem
	)

Draws a text on a device. Every text with every font that is installed on the system can be drawn. The functionality of this method is that the text (with its font size, width and style) is put into an image. With this trick text can be drawn like a normal image.

Parameters:

	p	contains the xy coordinate where the text will be displayed.
	textItem	is the text item with the text ;)

Bug:: rotates the text more than 90 degrees clockwise then the position of the text is incorrect.

void LCDPaintEngine::drawTiledPixmap	(	const QRectF &	,
		const QPixmap &	,
		const	QPointF
	)

Currently this is not implemented because this method is not needed. Send me mail when you need this method.

Exceptions:

UnsupportedException

bool LCDPaintEngine::end ( )

Draws the content in the buffer on the device.

Returns:: true on success, otherwise false

bool LCDPaintEngine::hasFeature ( PaintEngineFeatures feature ) const

Parameters:

feature

which you inspect

Returns:: true if the paint engine has the feature otherwise false

QPaintEngine::Type LCDPaintEngine::type ( ) const

Tell that our paint engine is a custom made engine

Returns:: QPaintEngine::User

void LCDPaintEngine::updateState ( const QPaintEngineState & state )

Only the transform state will be checked and set.

Parameters:

state

which state is currently updated

QBrush LCDPaintEngine::m_brush [private]

ControllerInterface* LCDPaintEngine::m_controller [private]

Active controller to access the device

QMatrix LCDPaintEngine::m_matrix [private]

Hold the transform status of an item (e.g. when you move an item around the matrix is changed)

QPen LCDPaintEngine::m_pen [private]

LCDPaintEngine Class Reference

Public Member Functions

Private Attributes

Detailed Description

Member Function Documentation

Member Data Documentation


Public Member Functions
bool	begin (QPaintDevice *)
void	drawEllipse (const QRectF &)
void	drawEllipse (const QRect &)
void	drawImage (const QRectF &, const QImage &, const QRectF &, Qt::ImageConversionFlags flags=Qt::AutoColor)
void	drawLines (const QLineF *, int)
void	drawLines (const QLine *, int)
void	drawPath (const QPainterPath &)
void	drawPixmap (const QRectF &, const QPixmap &, const QRectF &)
void	drawPoints (const QPointF *, int)
void	drawPoints (const QPoint *, int)
void	drawPolygon (const QPointF *, int, QPaintEngine::PolygonDrawMode)
void	drawPolygon (const QPoint *, int, QPaintEngine::PolygonDrawMode)
void	drawRects (const QRectF *, int)
void	drawRects (const QRect *, int)
void	drawTextItem (const QPointF &, const QTextItem &)
void	drawTiledPixmap (const QRectF &, const QPixmap &, const QPointF)
bool	end ()
bool	hasFeature (PaintEngineFeatures) const
QPaintEngine::Type	type () const
void	updateState (const QPaintEngineState &)
Private Attributes
ControllerInterface *	m_controller
QMatrix	m_matrix
QBrush	m_brush
QPen	m_pen