AbstractPainter

touchgfx/widgets/canvas/AbstractPainter.hpp

An abstract class for creating painter classes for drawing canvas widgets. All canvas widgets need a painter to fill the shape drawn with a CanvasWidgetRenderer. The painter must provide the color of a pixel on a given coordinate, which will the be blended into the framebuffer depending on the position of the canvas widget and the transparency of the given pixel.

The AbstractPainter also implements a function which will blend each pixel in a scanline snippet into the framebuffer, but for better performance, the function should be reimplemented in each painter.

Inherited by: AbstractPainterABGR2222, AbstractPainterARGB2222, AbstractPainterARGB8888, AbstractPainterBGRA2222, AbstractPainterBW, AbstractPainterGRAY2, AbstractPainterGRAY4, AbstractPainterLinearGradient, AbstractPainterRGB565, AbstractPainterRGB888, AbstractPainterRGBA2222

Public Functions

	AbstractPainter()
	Initializes a new instance of the AbstractPainter class.
void	framebufferToDisplay(int16_t & widgetX, int16_t & widgetY) const
	Convert Framebuffer widget coordinates to display widget coordinates.
virtual HAL::RenderingMethod	getRenderingMethod() const
	Return the applicable rendering method of the painter.
virtual void	paint(uint8_t * destination, int16_t offset, int16_t widgetX, int16_t widgetY, int16_t count, uint8_t alpha) const =0
	Paints a streak of pixels (all with the same alpha) in the framebuffer.
virtual bool	setup(const Rect & widgetRect) const
	This function is called before any actual paint operation is started.
virtual void	tearDown() const
	This function is called after all paint operation have finished.
virtual	~AbstractPainter()
	Finalizes an instance of the AbstractPainter class.

Protected Functions

FORCE_INLINE_FUNCTION bool	compatibleFramebuffer(Bitmap::BitmapFormat format)
	Helper function to check if the provided bitmap format matches the current framebuffer format.

Protected Attributes

int16_t	widgetWidth
	The width of the widget on screen, used by framebufferToDisplay()

Public Functions Documentation

AbstractPainter

AbstractPainter	(			)

Initializes a new instance of the AbstractPainter class.

framebufferToDisplay

void framebufferToDisplay	(	int16_t &	widgetX ,		const
		int16_t &	widgetY		const
		)	const

Convert Framebuffer widget coordinates to display widget coordinates.

This is handy when creating a custom painter and the X,Y is needed in the same coordinate system as the widget on the display.

Parameters:

widgetX	The widget x coordinate.
widgetY	The widget y coordinate.

See also:

AbstractPainter::paint

getRenderingMethod

virtual HAL::RenderingMethod getRenderingMethod	(			)	const

Return the applicable rendering method of the painter.

HARDWARE if the painter uses hardware based drawing, SOFTWARE otherwise. Relevant on platforms using DCACHE.

Returns:

HARDWARE if painter uses hardware based drawing, SOFTWARE otherwise.

Reimplemented by: touchgfx::PainterRGB565::getRenderingMethod, touchgfx::PainterRGB565Bitmap::getRenderingMethod, touchgfx::PainterRGB565L8Bitmap::getRenderingMethod, touchgfx::PainterRGB888::getRenderingMethod, touchgfx::PainterRGB888Bitmap::getRenderingMethod, touchgfx::PainterRGB888L8Bitmap::getRenderingMethod

paint

virtual void paint	(	uint8_t *	destination ,		const =0
		int16_t	offset ,		const =0
		int16_t	widgetX ,		const =0
		int16_t	widgetY ,		const =0
		int16_t	count ,		const =0
		uint8_t	alpha		const =0
		)	const =0

Paints a streak of pixels (all with the same alpha) in the framebuffer.

The first pixel to paint is at 'offset' relative to 'destination' (to be able to support 1bpp, 2bpp and 4bpp). The first pixel to paint is at the given 'widgetX', 'widgetY' coordinate. The number of pixels to paint is 'count' and the alpha to apply is 'alpha'.

Note that the widgetX, widgetY is relative to the widget in the framebuffer, not the display. To convert the coordinate to display widget coordinates, use framebufferToDisplay().

Parameters:

destination	If non-null, the pointer.
offset	The offset to add to the destination.
widgetX	The widget x coordinate.
widgetY	The widget y coordinate.
count	Number of pixels.
alpha	The alpha of the pixels.

See also:

AbstractPainter::setup, AbstractPainter::tearDown, AbstractPainter::framebufferToDisplay

Reimplemented by: touchgfx::PainterABGR2222::paint, touchgfx::PainterABGR2222Bitmap::paint, touchgfx::PainterARGB2222::paint, touchgfx::PainterARGB2222Bitmap::paint, touchgfx::PainterARGB8888::paint, touchgfx::PainterARGB8888Bitmap::paint, touchgfx::PainterARGB8888L8Bitmap::paint, touchgfx::PainterBGRA2222::paint, touchgfx::PainterBGRA2222Bitmap::paint, touchgfx::PainterBW::paint, touchgfx::PainterBWBitmap::paint, touchgfx::PainterGRAY2::paint, touchgfx::PainterGRAY2Bitmap::paint, touchgfx::PainterGRAY4::paint, touchgfx::PainterGRAY4Bitmap::paint, touchgfx::PainterRGB565::paint, touchgfx::PainterRGB565Bitmap::paint, touchgfx::PainterRGB565L8Bitmap::paint, touchgfx::PainterRGB565LinearGradient::paint, touchgfx::PainterRGB888::paint, touchgfx::PainterRGB888Bitmap::paint, touchgfx::PainterRGB888L8Bitmap::paint, touchgfx::PainterRGB888LinearGradient::paint, touchgfx::PainterRGBA2222::paint, touchgfx::PainterRGBA2222Bitmap::paint, touchgfx::PainterXRGB8888::paint, touchgfx::PainterXRGB8888Bitmap::paint, touchgfx::PainterXRGB8888L8Bitmap::paint

setup

virtual bool setup	(	const Rect &	widgetRect	)

This function is called before any actual paint operation is started.

This allows the painter to initialize variables and optional dma queues. This happens before the first scan line segment is being drawn. If the painter is unable to draw, e.g. no bitmap assigned to a bitmap painter, 'false' should be returned.

Parameters:

widgetRect	The widget rectangle.

Returns:

True if the painter is ready to paint, false otherwise.

See also:

AbstractPainter::paint, AbstractPainter::tearDown

Reimplemented by: touchgfx::PainterABGR2222Bitmap::setup, touchgfx::PainterARGB2222Bitmap::setup, touchgfx::PainterARGB8888Bitmap::setup, touchgfx::PainterARGB8888L8Bitmap::setup, touchgfx::PainterBGRA2222Bitmap::setup, touchgfx::PainterBWBitmap::setup, touchgfx::PainterGRAY2Bitmap::setup, touchgfx::PainterGRAY4Bitmap::setup, touchgfx::PainterRGB565Bitmap::setup, touchgfx::PainterRGB565L8Bitmap::setup, touchgfx::PainterRGB888Bitmap::setup, touchgfx::PainterRGB888L8Bitmap::setup, touchgfx::PainterRGBA2222Bitmap::setup, touchgfx::PainterXRGB8888Bitmap::setup, touchgfx::PainterXRGB8888L8Bitmap::setup

tearDown

virtual void tearDown	(			)	const

This function is called after all paint operation have finished.

This allows the painter to close down dma queues etc. This happens after the last scan line segment has been drawn.

See also:

AbstractPainter::paint, AbstractPainter::setup

Reimplemented by: touchgfx::PainterRGB565::tearDown, touchgfx::PainterRGB565Bitmap::tearDown, touchgfx::PainterRGB565L8Bitmap::tearDown, touchgfx::PainterRGB565LinearGradient::tearDown, touchgfx::PainterRGB888::tearDown, touchgfx::PainterRGB888Bitmap::tearDown, touchgfx::PainterRGB888L8Bitmap::tearDown, touchgfx::PainterRGB888LinearGradient::tearDown

~AbstractPainter

virtual ~AbstractPainter	(			)

Finalizes an instance of the AbstractPainter class.

Protected Functions Documentation

compatibleFramebuffer

static FORCE_INLINE_FUNCTION bool compatibleFramebuffer	(	Bitmap::BitmapFormat	format	)

Helper function to check if the provided bitmap format matches the current framebuffer format.

Parameters:

format	A bitmap format.

Returns:

True if the format matches the framebuffer format, false otherwise.

Protected Attributes Documentation

widgetWidth

int16_t widgetWidth

The width of the widget on screen, used by framebufferToDisplay()